A bloggery post about the the seriousness of science and figuring out what is important and while listening to the morning news, I hear:

Light Drinking Might Help Keep Women Slim

and they go on to give their findings of the 19,220 women studied and how a link is found between moderate drinking and not gaining weight. The study's author Dr. Lu Wang, an epidemiologist with the division of preventive medicine at Brigham & Women's Hospital in Boston states several possible reasons including:

"Among women, those who regularly consume light-to-moderate alcohol usually have a lower energy intake from non-alcohol sources. On the other hand, alcohol intake tends to induce increased energy expenditure beyond energy contents of the consumed alcohol in women. Taken together, regular alcohol consumption in light-to-moderate amount may lead to a net energy loss among women."

Hmmmm, Really? Oh my, what have they discovered? I wonder what kind of increased energy expenditure it could be? Perhaps that explains the plethora of 2am female joggers and crowded ladies night at fitness gyms after the bars close.

So while pondering scientific studies may as well dive back into unraveling more in the wonderful world of sound.

Hey, is anyone interested in an NL4 tester version of the Rat Sniffer? The prototype is done and it is a two ended tester that checks for every fault in NL4 cables. Like the Rat Sniffer, this is a field use product that allows you to test NL4 cables when the cable ends are located at a distance from each other.

These are high quality machined aluminum and based on the same patented circuit utilized in the Rat Sniffer testers and tests for every possible short, open and miss-wire ALL GREEN = CABLE IS GOOD. No on off switch to worry about and they use the same 12 volt replaceable remote key chain alarm battery as the Rat Sniffer as well.. I am trying to gauge how many to make on this first order so if you are interested let me know. I am going to make first production run of US made custom machined units priced at $120 per send receive pair plus a free rat shirt and serial numbered warranty card for helping me get these things rolling. Soon to follow will be an NL8 version an then a Cacom unit as well. Also, if you do buy them and don't love them, send them back and Rat will do a full refund.

**** Sound Nerd Speak ****

So I am watching this AES panel video on the perceptions hearing

http://www.audiodesignline.com/showArticle.jhtml?articleID=222700732

and as much as I agree with the discrediting of scammers, and the undermining of audio voodoo, I also prickle at the arrogance of assumptions. Especially when what starts out as a clear and believable scientific observation becomes blurred as opinions of perception leak in. I so agree with keeping things in perspective which of course involves first establishing a well grounded and valid viewpoint to start with.

Let me clarify perspectives. On one hand we have the perspective of believers, 'the anything is possible crowd,' where the sky is not the limit, possibilities are endless and whether the concepts are repeatable or provable is not near as important as the fact that they were written, thought or spoken. On the other side we have the perspective of huddling skeptics, the self proclaimed 'investigators of verifiable proof' building the world of science, based on identifying dependable repeatable concepts from which real-world functioning successes can be built.

Both the believers and the skeptics inspire massive rivers of money flowing to support their respective causes. Both construct items of perceived value and usefulness. Both sell or pass freely their thoughts and revelations to attract others to swallow and follow. Whether it is a crystal that heals, an automobile that transports or a process of thought that helps one navigate one's life, they are both trains of thought with long and twisted histories peppered with successes and misconceptions over the years. Due to their differences in perspective, neither is able to truly resolve the expertise of the other. The pure skeptic can no more prove a certain type of music is beautiful than a pure believer can construct a cell phone that actually functions.

It is easy to to understand why science is useful and easy to feel why adding the complexities of beauty and art improves our lives beyond the monotony of what is purely utilitarian.

So what is the problem?

It is the middle ground, that gray area between fact and recreation where science encounters discomfort. The things we purely feel or think we know that science has yet to be able to adequately encompass.

The credibility of science comes into question when we are told that something can't be heard yet we do hear something. In our own confusion when we believe we have taken every variable into account only to find the most remarkable surprises still remain. These false assumptions are the feeding ground for the tangled garden of ideas for believers in magic and mystery. The Skeptics are doing all they can to excavate and form clean rows of well organized thoughts while the Believers immerse in weaving fact and fiction into complex and intoxicating stories and patterns. And yet a third perspective exists wherein both viewpoints are viewed as desirable, sellable, marketable and therefore useful.

Regardless of the propagation of education, I will personally make the jump to the conclusion that our world will always contain some balance or ratio of Believers and Skeptics. It is impossible to live our lives without the rules of science, just as it is impossible to live without the influences or art, pleasure and those magical stories affecting our lives. So let me call the beliefs that have a low level of probability and are grounded in floating perceptions, 'art.' I will refer to the beliefs that have high degree of provability and therefore probability, 'science.' It is when one side denies the relevance, the importance and/or the necessity of the other that voids are created allowing pseudo-science and other forms blurred perspective to gain traction. When art attacks science or visa-versa it just undermines it's own integrity. To tell an amazing story is one thing, to claim it is true is another. To measure the various nuances in sound is one thing, to claim it can or can not be heard is another.

So just as I laugh at the absurdity that people actually buy colored stones to tape to their audio cables in ignorance of the astronomical improbability that there will be any form of realizable alteration of the sound, I also believe that it is the failure of the science world to embrace the unknown that allows this ignorance to fester. And yes, science does try to quantify the importance and realities of art, and the world of art-thought tries to encompass science as well. Science teaches us that there are things that are known and things that are not yet known. Art teaches us there are things we 'know' and feel that defy definition.

We feel, yet science is typically by nature methodical and cold. The attractions to the warmth of mystery inspires the desire to circumvent being characterized and labeled as a predictable reproducing food eater. We know in our minds that we see, feel and hear so much more than even the most complex analysis system seems account for. Science's downplay of the cumbersome and its inability to adequately explain everything leaves the door ajar for people that will believe anything. Not that they wouldn't grab bit or real info, twist and run with it anyway

So anyway, back to the video. I am watching and enjoying the clarifications on human perceptions yet as and as the video progresses to the "what we can and can not hear" I find myself feeling swindled a bit and tempted to jump to conclusions and thinking that if the power of suggestion can inspire us to hear things that are not there, would not the opposite also be true? As the various sounds are played, are we convincing ourselves we can't hear them? What about cumulative effects of several independently inaudible aspects combining? Just as it is important not to jump to the assumption I can hear something, it is equally important not to jump write off something as audible or relevant without doing due diligence. In the end though, and in defence of the demo, a clear point was repetitively made; "this is just to help keep things in perspective" and with that I concur.

And with that lets take a big huge step back and ask ourselves "What would this accurate audio reproduction sound like if perfected?" How can we determine what is or is not important for audio accuracy if we have yet to create audio accuracy? Whether $10,000 audio cables are used or 192K converters and razor flat mics, the real story is that at the end of the day has anyone ever heard a recording played back where you tried to search around the room to find where the live band was hiding? How come we can know there is a garage band rehearsing a block away and when you sit dead center in front of the best sound systems money can buy and close your eyes, the best we can get is a descriptive range of similarities to live?

What if one side or the other was truly able to prove their position? What if those pricey cable companies with colored rocks put together a system that when turned on, you would swear up and down that there are actual musicians in the room. Would it sell systems? Would it sell cables? If they could do it do you think they would? Would that not be a game changer? Then they could show that vinyl is more realistic than CD's, or that it no longer sounded exactly real without the faster D to A converters or fancy power cords. The room would not matter, just as the room does not matter with that garage band. "Oh, you were playing live in a crappy room so I thought you were a recording" Yeah, right.. Has anyone ever heard sound reproduction so clear that you were unable to tell it was not in real time? I haven't but when and if I do, it may be a good place to start testing truly whether some of these products and concepts actually function.

**** End Sound Nerd Speak ****

Oh, check out these pages

Play this auditory illusion over and over and it should sound like it keep rising in tone:

http://www.moillusions.com/wp-content/uploads/2006/05/shepards.mp3

And some more illusions and an interview with Poppy Crum who rocked one of the more fun presentations and clearly has one of the the coolest names ever!

http://www.cogito.org/interviews/InterviewsDetail.aspx?ContentID=17862

A bit more about James "JJ" Johnston:

http://home.comcast.net/~retired_old_jj/

And Ethan Winer

http://www.ethanwiner.com/audiophoolery.html

And finally in my long winded word wanders it looks like Coachella adventure is coming up quick. Oooooh big huge audio playground!

Dave Rat

Oh the joys of re realizing the same thing over and over again. I have the attention span of a windshield wiper. As if it is some great revelation I was out surfing this morning and pondering the less than thrilling weight of affairs of many of the projects in which I am immersed and then it dawns upon me. Heck, it is just winter darn it. I know this, I always know this, Winter is slow, sluggish resistive and lackluster for a touring rock n roll human, except for surfing and the snow sports. Anyway, I guess another way to look at it is I can feel the excitement of summer rock shows and general happiness looking and it makes me happy.

Occasionally in life we stumble across things that touch our hearts and bring us great concern. While driving home the other day I was shocked and dismayed to see this:

Yes, Share the Road! What the hell are they thinking? Road sharing is stupid. Oh wait, no, that's was not it. Oh that's right, it's the Unfree Tree! Truly a travestree. Caged and no longer free to roam and hunt it will surely starve to death. What crime could this tree have committed to deserve this? I don't know, but I do know that I had no choice other than to do what I am sure everyone of you is thinking right now. WE MUST HELP FREE THIS TREE!

So with the help of my daughters we started a Free the Tree page on Facebook. http://tinyurl.com/yz4j5nv Though we have no idea how it will help nor a plan or strategy whatsoever, if you feel so inspired, please join to help save the Unfree Tree!

**** Sound Nerd Speak ****

In case ya have not noticed, the cold, yes cold! it gets down to the low 50's here sometimes at night, weather has me spending more time indoors protected from those fierce elements. And what better to to do with some shacked up home time than to pull out the video camera and the power tool and spend some quality time undressing a few of the hottest wedge monitors on the market.

And if that is not enough, I had a great time playing Lego blocks with the new final production model EAW MicroSubs that arrived last week.

Hey, check out the mysterious ne L-Acoustics box called KARA

I guess the big debut is going to be at MusikMesse Frankfurt. Is what I see a mini K1 version as dV-Dosc is a mini V-Dosc? oooooh!

Ok, let me ask you this. How many of you know the difference between a 'Free Field' and a 'Random Incidence' measurement microphone?

http://tinyurl.com/yzql4wf

Ha, some tweaky stuff going on there! And to think that a cheap mic and an old sketchy RTA is more than enough resolution to easily weed out 90% of the headphones I tested.

I thought this was a quite credible and convincing test of doppler versus phase distortion that seemed to coincide with the simple testing I did http://www.youtube.com/watch?v=f-XPawd5unk

**** End Sound Nerd Speak ****

As much as I enjoy new adventures, it is just such a can o worms. So we have been looking for awhile to revamp the Rat Sound web site which is in dire need of a face lift. We actually have started the project twice with two different web designers and I guess a combination of cumbersome and bad luck have us still in limbo. So frustrated as I am I decide "hey, I will just catch up a bit on web site skills and dial in something till we can get her done right." Heck, just deciding what we want is a major challenge.

Anyway, so I buy a few books yesterday and dive into the sore eye screen stare while fumbling pages both paper and web. Wow, I don't know if I am happy stunned happy or just so lost in the ether world that it no longer matters. Either way, I have been using the daverat.com page as a test bed and there is some really cool stuff out there, though I am not sure I really know how a lot of it works.

What I think I know is that I was able to copy bits of code and embed my twitter site using a profile widget so that my last 4 tweets are shown. Using Feedburner's BuzzBoost I was able to embed this blog, and the Rat Sound Message Board such that the most recent posts are shown and automatically updated. I found that I could create a custom Youtube video player that auto updates and drop it into the page as well. 

If all works as precariously planned there is a bucket brigade of events all now interlinked where soon after I post this blog, feedburner will grab it and generate a tweet which should be grabbed by myspace and facebook updating my status as well as send off stuff to various unknown locations related to whatever those little check boxes I was having a party clicking upon. Why you wonder, or maybe that is me wondering. I can honestly say I do not really know other than the nerdiness of seeing if it all works. To spend massive amounts of time in order to save barely any. Or perhaps I just like opening big cans of worms just to see where they go.

And I am sure that all this is just elemental kids stuff but none the less, it bends my mind in knots and I am only on day 1 though not sure how long I will last. Oh I so crave the relaxing peaceful sensation of mixing a great big giant rock show.

The Mighty Headphone Quest

Is winding down as I settle in on three so far. I have a few more still coming in but for now the Denon AH-D5000 and Denon AH-D2000

are my favorites. Big, no folding expensive headphones that truly do sound impressive. Ha, isn't that just my luck, figures that the best headphones I can find are in the Denon consumer line that Rat Sound does not even have a dealership for. Oh well, I never would let that bias the testing anyway so it is actually kind of cool. In second slot and a bit more reasonably priced are the The Ultrasone HFI-680's

and they scored really high with clean HF, solid LF and they fold up as well. And darn it, Rat did not sell those either, but the folks at Ultrasone are super cool and we worked it out a to be an Ultrasone dealer now. The Shure SRH-840's came up well as well. Spare earmuffs, removable cable and foldable, they are a bit dark sounding but robustly built and solid.

I also did stumble across something I thought was interesting. If I turn up sound in one ear and leave the other ear off on some headphones I hear some sound in the ear that is of and in other headphones I do not. Furthermore, the sound I do hear, though low volume, it is not great sounding and tends to be distant and resonant. I hope to do a test and measure it. I am thinking possible factors are with whether they use 3 or 4 wires from the connector, wire length and wire thickness used in relation to driver impedance.

Ok, so what next. Oh, here is a video I put up a while ago and what is really whacky is if you look at the comments people leave me.

Ok, I am soooo curious to see if this whole posting thing works like a domino chain or a house of cards. Oh and if you have comments or suggestions, love to hear them!

Dave Rat

So I am listening to the news and all this hullabaloo about issues the instantly undrivable Toyota cars and as the story unravels it seems to be steering in the direction of two primary issues. First, there are cars that are doing something that the driver does not want, I.E. accelerating without being told to do so. The second issue arising is related to the cars not doing as they are in instructed, I.E. continuing forward when instructed to stop.

Now answer me this. We keep hearing reports that the acceleration issue is related to throttle linkage. Hmmm, does that make sense? How does a mechanical connection decide on its own to accelerate and tell the car to move faster? Hmmm. Now there are reports of a computer processor causing delayed braking on Prius models that actually do make sense and it is beginning to sound a bit familiar. Something about software and glitch and delay. Hmmmm, that has never happened before, oh wait, except everyday on just about everything computery I own. Could it be that cars are finally catching up to where our laptops have already gone and our digi live sound boards are deep into going? That wonderful digi ether world where our actions are analyzed and what actually occurs is some mathematical processed interpretation that we cross our fingers will actually occur in a timely manner? It is true that no longer does stepping on a gas pedal actually move a mechanical butterfly in a carburetor but instead initiates whole series of calculations and e-decisions which arrange a multitude of things in such a way as to hopefully inspire the car to move in a forwardly direction. Not unlike our new world of audio where the actual audio signals no longer need to even enter the knob and fader units we use to control them. Boot-up times and turning a knob results in stair steps of audible gradations after waiting that awkward fraction of a second for the console to get done calculating what it is you asked it to do.

Don't get me wrong, I love my laptop and rely on my cell phone with a smile. But would I use either of them to control the brakes or accelerator in my car? Perhaps I would but that would indeed add a new dynamic of cautious awareness to get my head around. And what about our non life and death world of audio? I must admit that as one who still is holding on to enjoying the fading world of analog mixing, I smile knowing that arbitrary acceleration and braking while awaiting a software update are two issues I do not have to worry about happening mid rock show.

Ok, enough useless but fun babbling, lets get on to the important stuff. There are so many concepts I have wanted to unravel and yet never had a method of documenting and demonstrating them that is enjoyable and easily shareable. In my latest video adventure I figured out a simple way to demonstrate the difference between pickup patterns of some popular vocal mics. I have been using om7's for years on artists that stay on top of the mic (sing with their lips against the mic grill). I have read and heard some pretty interesting and colorful opinions and comments on why one mic is better or worse than another but rarely are these opinions qualified with supporting facts. Also, recently I have spent some time and effort developing and manufacturing an adaptor to mate Audix mic capsules with Shure wireless transmitters. Why? Well, I made a video that answers that question.

Also, I have two more videos up from the Mighty Headphone Quest showing the low frequency volume testing on some of the cans. I have it narrowed down to three pairs so far but new headphones to test are still trickling in.

And oh, thank you Matt and Paul

for taking care of me at the Musicares gig.

I reluctantly forgive you for putting me on a PM5D because as much as I hate to admit it and find them no fun to mix on, it was the right tool for the job with so many bands, it just made sense to roll digi. It was only one song but it was also the first show with Chili Peppers rocking the new guitar player Josh. All good, this is going to be cool, cant wait till the show hits the road though it will be a while.

Finally for today, say hey to my new roommate Bones

Ok, off to ponder my next adventure.

DR

So my headphone testing continues and I actually think I am finding a few pairs that match or beat the Sony CD3000 reference pair. There are many inter-related factors to look at:

• Frequency Response
• Sound quality
• Maximum usable volume
• Isolation
• Fit
• Comfort
• Size
• Cost
• Cable type and length
• Construction quality
• Service-ability
• Any special features and on and on

I am going to do my best to eliminate any opinions and focus on the relevant measurable aspects. So first I started with flat response. Why? Well heck, if you have a pair of super wide response super low distortion headphones but half the frequencies are twice aloud as the others, what good will it do us?

"Oh yes, sir, oooh, you are in the business of accurately reproducing color images for huge crowds? Well take a look at this video projector, It is an amazing, high resolution and very accurate for everything except everything that is the color red will be twice a bright as anything color green and you can barely see blue at all." Crazy business!

So I believe that an even frequency response is the most obvious and basic of requests. I am testing testing with leniency and what I believe to be a sloppy spec of + or - 4 db from 30 to 12K. Furthermore, I do my best to get every pair to pass and whenever possible and give them the benefit of the doubt if they are even close. At this stage it is not about eliminating as much as it is about finding.

I realize my test methods lack many of the high tech perfectionistic angles and that is intentional. I don't know about you but I have personally read some pretty amazing claims about various pieces of audio gear and have seen many accurate and complex test setups constructed to reinforce claims stunning sound quality only to find out that the testing done is focused on a small aspects and offers an incomplete story of the big picture and real world experience. I have also read many profound and ludicrous claims of audio wizardry backed by false logic, pseudo science and blatant lies with no form of testing credibility.

My goal here is to side step both of the overly technical and voodoo magical angles by offering some simple logical and inexpensively repeatable testing that will hopefully allow people to draw useful conclusions as to what to expect from the various headphones.

So first I sought out flat response and thinned the pack a bit and now I am ready to move on to the phase 2 challenge. I am now going to subject all the headphones that meet or are close to the + or - 4 db spec to a low frequency volume test. My experience has been that it is very difficult for headphones to cleanly reproduce very low frequencies. Another issue I often run into is headphones that just do not have enough output and are incapable reaching adequate volume levels without distorting. I guess the question to be pondered is "What is an adequate volume level?" Well, I personally tend to mix around 103db to 105db A-weighted and and 110db to 112db C-weighted or flat weighted. Since I am looking for live sound headphones, I believe it is reasonable to expect the headphones I seek to reach actual show volumes. This way I can PFL the instruments at the same volume I expect to hear them when the PA is on and if they have a reasonable amount of isolation, I will be able to hear the headphones over the PA during the show.

Hmmm, a goal and a test setup. Ok, how about a tone generator on my laptop run into a power amplifier (BGW Model 85) into the headphone under test. Then a mic to measure the output of the headphones, an oscilloscope (HP 1715A) and an RTA (Klark Teknik DN60) to see the waveforms and use the other 1/2 of the power amp to power a speaker (an old Rogers Studio 1 BBC Studio monitor) so I can hear the waveform as well. Simple, easy and I can put it all together with stuff I have laying around the house here.

Here is what I am going to do:

#1) Send a 100 hz tone at a level of 110db flat weighted in the Sony CD3000 headphones. The volume level will be roughly determined by the RTA's overall level meter and the oscilloscope will show the peak to peak voltage. I will them match that peak to peak voltage for all the rest of the headphones I test. I have the oscilloscope set to .5 volts per division and 110db flat weighed shows up as 3 volts peak to peak (6 divisions on the scope screen).

#2) Without changing the voltage sent to the headphones, proceed to sequentially test with tones at 100, 90, 80, 70, 60, 50, 40, 30 and 20 hz while monitoring the output waveform on the oscilloscope and listening to the speaker. I will be looking for the 6db down point (1/2 peak to peak voltage) and note that as well as any strong distortions in the sound or waveform.

#3) Eliminate the headphones that perform poorly and while contemplating the next round of testing.

For the test setup, I have a mic fitted into a drilled hole in a piece of wood that I wedge against one muff of the headphones. I do my best to form a good seal and move the mic around till I get the best readings I can. To keep this blog post from getting crazy long, I am posting the most relevant waveforms rather than every single one.

Sony MDR-CD3000

Ok, here is a good looking 60hz waveform. 100, 90, 80 and 70 all look and sounds fine. There is a bit of sub harmonics showing up at 30 hz but the sub harmonics tend not to be too intrusive sound wise.

At 40 HZ it starts to drop in level a bit and it is begriming to deform a bit from a clean sine wave.

30 HZ is about the 6db down point and ignore the double traces. The waveform is clearly distorting and you can see the harmonic distortion causing 50 hz (4th from left) to rise on the RTA

and the 20 HZ is at about 1/3 the voltage and the waveform is fairly triangular. For visual consistency, I am not altering the sweep or range on the scope for any of the tests.

As you can see the waveform kind of falls apart but it did make it down to 30 with a reasonable amount of output.

So next lets take a look at the trusty and loved Sony MDR-V6. Since the V6's are pretty much the McDonalds burger of live sound headphones, I will post more read outs so there is a good comparative reference. The 100 hz looked good and here is 90 HZ which also is good but has a slight drop in level of a fraction of a db.

At 80hz we are seeing the waveform begin to distort and become a bit more triangled as the tops curve rightward a bit.

The waveform continues to degrade at 70hz and down from 3 volts to 2 volts PtoP.

And here is 60hz with a significant amount of harmonics showing up on the RTA and quite audible.

50Hz

30hz

and 20HZ

Hmmm, these waveforms are pretty warped as the V6's are not happy with these frequencies at these levels. The sharper the points on those waveforms, the more HF buzz and worse the sound is. Also, look at the RTA. Each tone should be a single or double LED column with the sides dropping off. When you see two peaks with a space between them, that represents harmonic distortion, If the second peak is below the primary, that is not too bad. But when the peak is above like the 40hz harmonic above the 20hz in the pic above, then it is really audible. We were seeing similar issues with the CD3000's as well but it started at a much lower frequency. I am going to cut the V6's out of contending for "The Best Live Headphones" but maybe for a good live headphone for under $100, they could be the way to go.

Ultrasone HFI 680

At 80 they look good

At 60 there is actually a boost of a few db

at 30 there is some triangulation and harmonic distortion at a 50hz but they are holding level quite well

I forgot to shoot the photo of 20HZ but it shows less than a volt down and some triangulation to the wave but nowhere near as severe as the V6's were at a much higher frequency. These continue to be one of the best headphones I have tested so far and they get to carry on to round three.

On the Sennheiser HD25-1 II's at 70hz, you can see they look pretty good. (ignore the double trace)

Here they are at 50hz, down a volt and not looking so good

but I found that some of these headphones are a lot more susceptible to low end variations due to the amount of squeeze against the test setup (or my head). I am sure you have all found that when you squeeze some headphones tight against your head the low end gets louder. Well the headbands on the HD25 are actually quite tight as well so I tested while squeezing the ear muff tighter and dropping the drive voltage level (the scope is on .2 volts per division for this pic,) and re calibrated for the extra volume and now look at 50

Here is 30 at normal pressure

30 at reduced level and more pressure, notice the cleaner sine wave.

And at 20Hz with normal test pressure and level they are just under 2 volts down.

Looking pretty good for over the ear headphones and surprisingly superior lows over the V6's yet not up to par with some of the others. Remember, these had a very flat frequency response so on to round three.

Wow, the Sony MDR-V600 already start to lose shape at 80hz,

Bouncing back in level at 60hz but still asymmetrical rounding on the top of the waveform

Degrading severely through 50 and 40 to a clearly clipped waveform at 30HZ

and I wont even bother showing you 20hz, say by bye to V600's.

Sennheiser MD280 PRO are looked pretty good at 80, But uh oh! Looks like they are not going to fair so well. Check out 70 hz!

But wait, they come back to life if I rest the back of them gently against anything that is rigid with some mass.

My finger does not work but barely touching this little amp or the wall snaps the response back to life. You can feel the slight flexing of the plastic as well when I send a tone to them.

Really strange, it appears the plastic housing is flexing and canceling out the low end. Here they are at 40 when scooted against that amp (ignore the double traces as it is just mis triggering on the old scope.)

and here they are moved and not touching at 40.

With a 3db down point at 20hz while resting against the amp

and a fairly clean sine wave as well, these will have to stay in the mix while I contemplate the whole "has to touch something" oddity.

The AKG K271 MkII headphones came in last week. One thing really cool about them is that they actually turn themselves off when you take them off your head. Very cool but drove me crazy trying to test them till I figured it out. They tested up quite well with frequency response on the RTA but rather than backtrack here, I am going to drop them straight into the low end level testing. Here they are at 100

With a bit of a peak at 70 HZ they came back to a pretty good level but some distortion at 50

progressively sloppy down to 30

and 20 is a mess. But, when I lowered the volume 10 db, they really cleaned up and come up quite nice all the way around. I am going to drop them from the top contenders while also recommending them as an awesome set of headphones for lower volume monitoring, especially if the auto off feature is an asset to your application. I will post the frequency response at some point as well.

So I had a pair of Shure SRH 840's and the demo ended before I was done testing and I sent them back. Of course I then get hit with so many requests to test them I have to reorder a pair. Here they are at 100

Getting a few db louder at 80

Still hot at 60 but fairly clean with a bit of sub harmonics rising.

Back to normal level at 50 and 40 and starting to drop at 30 and become more triangular.

With 20hz about 10 db down but reasonably well shaped compared to most

These are looking better than I expected and will have to see how they do on frequency response test.

Next up, the Denon AH D2000. Oh my. Check this out! Here they are at 70

Still holding strong at 50 with a nice sounding sine wave and some sub harmonics coming in at 30hz

A nice sine wave and no drop in level at 30hz yet harmonics at 50hz are up

Barely any level down at 20 and still a clean waveform!

and look! not even 3db down at 15 hz! (Yes, forgot to re label the pic from 20 to 15). These are so impressive I have just ordered a pair of the top of the line of that series, the Denon AH-D5000's that I will test for ya when they come in.

Ok, so that leaves us with five pairs plus the reference Sony CD3000's and the Beyer 770 and Denon D5000's that are on their way to me next week.:

Model	Disqualifier	Listening notes	Comments	Status
AKG 271 MKII	Low Volume		Still Waiting Arrival	Out
Allen & Heath XONE XD-53	Not Arrived	HF-	Still Waiting Arrival	Out
Apple iPod ear buds	Ear buds	ULF, LF--,	Bye bye, ear buds	Out
Audio Technica ATH W5000	Response	ULF-, HF-, UHF-	Smiley Curve	Out
Audio Technica ATH AD700	Open Ear	H-, UHF-	Clear, Very Flat	Out
Audio Technica PRO700	Response	LF++, HM-, H-	Bass heavy, powerful	Out
Beyer DT770	Not Arrived	ULF-, UHF+	Tonally Close
Denon AH-D2000		HF-	Tonally Close	Round 3
Denon AH-D5000	Not Arrived
Equation Audio RP-21	None yet	Smooth, HM-, UHF+	Removable straight cable	Round 2 but demo ended
Equation Audio RP-22X	Response	Smooth, LF++	Removable coily cable,	Out
Grado SR60i	Open ear	ULF--, LF-, HF+	Low end light	Out
Koss ESP-950	Open ear	ULF-	Tonally Close, no isolation	Out
Koss MV1	Response	MID++	Cool no tangle coily cable	Voice optimized
Koss Portapro	Open Ear	LF+	Sound great!, small open ear	Bye Bye, open ear
Koss Pro4AAT	Response	ULF-, HF-, UHF--	Cool no tangle coily cable	Speech optimized
Pickering OA-3	Vintage low-fi	Yuck!	Never a contender	ouch!
Sennheiser HD 25-1 II	On ear		Tonally close	Round 3
Sennheiser HD 280 Pro		HF-	Tonally close, a bit dark	Back in, Round 3
Sennheiser HD 380 Pro	Response	HM--, HI-	Very smooth, LF clear	Hi-Fi but dull HF
Shure SRH-840		LF++, UHF-	Removable cable	Round 2.5
Sony MDR-7506	Round 2	ULF-, UHF-	Tonally close, lacks ULF, UHF	Out
Sony MDR-7509HD	None yet	ULF-, M+, H-, UHF-	Midrange heavy, Smiley curve	Out
Sony MDR-90	On ear	ULF-	Tonally close, discontinued	Out
Sony MDR-CD3000	Discontinued	Ref	Ref
Sony MDR-V6	Round 2	ULF-, UHF-	Tonally close, Lack ULF, UHF	Out
Sony MDR-V600	None yet	ULF-, UHF-	Tonally close, harsh	Out
Sony MDR-XB700	Response	ULF++, LM+, UHF-	Too much LF	Out
Ultrasone HFI-450	Response	L+, M-, H-	Low heavy	Out
Ultrasone HFI-680		Smooth	Tonally Close
Ultrasone HFI-780	Response	UL+, H-	Midrange below spec	Out
Ultrasone PRO 900	Response	UL+, LM-, M-, HM-	Removable cable, Lacks mid	Smiley Curve

As this test adventure progressed I have reinstated the Shure 840 as I never got a proper RTA reading on the first set that I had to send back when the demo ended.

I have found that I am getting better readings on the Sennheiser HD280 PRO's if I put some pressure on the outer shells so brought those back in the mix.

I wanted to continue testing the Equation Audio RP21 headphones with a removable cable and nice price point but for some reason they rushed me to get their demo pair back faster than I was able to put time into testing them for round 2. I don't think they would have made the "A" list but they do look like they have the potential to beat the V6's in the "under $100 street price" range.

I have been getting requests to test several other pairs from various manufacturers that I will gladly test if someone wants to send me a pair or if I can get some substantial credibility that any of those headphones have a strong chance of beating the top level cans I have already, I will consider purchasing for the test.

Will try and do a video in the next few days or so showing these the test methods and such so you can hear the top contenders as well. Here is a link to the video's so far. Cool cool, till next time rock on!

DR

So as part of the Mighty Headphone Quest, I guess I am going to have the Mighty Headphone Sell Off.

I had to buy several pairs to get them tested and here are the first two and though they did not make the cut for the application I have outlined in this quest, they are still quite good and well loved headphones. A brand new till I opened them pair of Sony MDR-7509's and a brand new till I opened them pair of Grado SR60i open ear. If any bloggery friends buy them, we will toss in a Rat shirt and some stickers as well. They are up on ebay but just send us a note if ya win 'em and we'll hook you up.

Sony MDR-7509HD

Grado SR60i

Ok on to the more mundane. Simplicity, Complexity and Believability. I have been thinking a bit more as I try and hack away the cobwebs of complexity and I think I may be gaining some momentum. The desire to overcomplicate and mask clarity is irresistible, especially when it fills wallets. I do not believe it is tough, though. I believe when accomplishing the purest task is a formidable challenge, that to mask various levels of failure, distractions are introduced in order to overcomplicate something that is easily observed when left in it's simplest state.

So as I dig around in the vast diversity of products available. Each product is claiming to have some group of assets that are superior in some way to the asset group of the other products. Maybe one pair has a certain combination of is cheaper or lighter, more comfy, stylish, durable, louder, flexible, available, socially conscience in the manufacture or whatever and on and on and on and I know that the importance of sound really depends on the application intended, budget allotted and expectations that are set. But unlike price or weight or looks, sound quality opinions have somehow has taken on this supernatural aura that requires elite audio monks from the netherworld of golden ears and fuzzy logic. And ears golden as they may be, maybe, just maybe, at least, at minimum, if the sound that comes out is somewhat close to the sound that goes in, perhaps that may be a good place to start? And when I find perfect sound, I will know it. I will not need magic ears or special wires or voodoo crap of any sort at all. I will merely close my eyes and be completely unable to distinguish between where I am and whatever elsewhere the music has taken me. Everything else is just a feature or preference.

And does anyone know the model # of these Sony mystery headphones?

Dave Rat

So I have been working on a few new projects, one is an Audix to Shure Adapter that allows an Audix wireless mic capsule to mount onto a Shure wireless transmitter. The concept originated from our friend George Squires that mixes monitors for REM. Though Audix makes a wireless unit, it just is not of the caliber of the deep pockets Shure products. While Shure makes many very high quality mics, they just do not make a high gain before feedback mic that can keep up with the some of the Audix offerings. So, when you have a band that relies on the assets of an Audix mic yet needs wireless, it has been a bit of an issue. Switching to a different mic type mid show when the singer wants to wireless wander really sucks. So we made a couple prototypes for REM's last tour but they were just metal threaded adaptors and needed to be soldered to work. Now we have made a batch that just screws right on and allows any Audix capsule make a connection with any Shure transmitter. If you are interested, there is more info at http://www.ratsound.com/soundtools/

Okey Dokey Smokey. Plants not Animals!

Speaking of making connections and solutions, though I never mentioned it, for the past two years I have been battling a miserable on and off increasing bummer of a building sinus issue. It started pretty mellow and gradually built into headaches, blurry vision, light sensitivity and constant sleepless pressure that left me always tired and never fully coherent feeling. Five doctors, 2 MRI's and a Cat scan, antibiotics, a pile of natural based neti pot concoctions, cameras in the head, steroids, hot steam and on and on and on. That helpless unsolvable dredge of a feeling where everyday feels like rubbing bicycle brakes on an uphill pedal. Aaaargh! So once again I reach one of the many, "Hey, wait a minute, this is just not right, this is not normal, I must attack once again" points, calling the doctor, fed up I tell them I want to go the hospital or whatever this takes. So they give me an appointment right now and less than 30 minutes later I am in the his office hearing the same old rap. "Hmmm, yes, hmmm, ok, well I am going to prescribe blah blah blah." Hey wait, that's what you and every other doc has told me before but with no other immediate option I humor the response and whilst I try and form a new plan. But this time he says something different. "Hmmm, it's not bacterial, so antibiotics wont help, it's fungal based." Going to give you a seven day prescription that should clear it up. Oooooh, fungal is plant, and all this time everything has been focused on fighting little critters as bacteria is animal. Well new is good and worth a shot I guess, so I get to the pharmacy and they hand me these packets of huh? "For Vaginal Yeast Infections!" Yikes, that caught me off guard and sent me mind a wandering. I did a bit of research and found:

http://www.sciencedaily.com/releases/1999/09/990910080344.htm

That was 4 days ago and though I am not fully head pressure free, damn I feel a million times better like I no longer live my life walking around in a bowl of jello with spike in my cheek. I just hope it lasts but for now I am sure happier.

Lets see what else. The Mighty Headphone Quest continues and I have put up a few Youtube videos on the subject. You may notice a bit of difference in the readings as I have switched to a different microphone that is smaller and seem to read the HF a bit better on some headphones. It is interesting how some of the headphones are really sensitive to slight placement variations while others are not.

Hey, I have been getting requests to test some more headphone models which I will gladly do. But, since I do not have an unlimited budget on this and getting demo's can be tough with companies Rat is not a dealer for, I figured I would send a shot out:

If you have a pair of headphones you feel are worthy contenders and do not mind sending them to me for a 4 or 5 days, I will add them into the test mix and youtube the results. And thank you Bob Rice for the Sony MDR-7509 non HD's!

More audio nerdery! Hurray! Want a super cool free downloadable sine wave generator? Check out

http://www.tucows.com/preview/502787

Or how about a free version of Electri-Q' - posihfopit edition' is a simple, intuitive, but powerful minimum phase EQ?

http://www.aixcoustic.com/index.php/Electri-Q-posihfopit/30/0/

Or perhaps a parametric graphic equalizer with excellent response all the way up to Nyquist?

http://magnus.smartelectronix.com/#NyquistEq

And nothing like a trip to the beach with the pooch to bring a smile.

Dave Rat

Oh, and since not everything can always run smoothly and issues are bound to occur, please view the following instructional video teaching advanced troublshooting techniques.

And double oh, Greg Cameron sent me this link to a Pro Sound News article on Blink 182.

http://www.nxtbook.com/nxtbooks/newbay/prosound_200912/#/60

Finally we are actually seeing something show up with some potential! As I go through them, one thing keeps coming to mind. How in the heck can all these headphones have these amazing specifications of 20 to 20K, 5 to 30K, 6 to 42K with each one inferring that it is flatter, wider and more accurate than the last when there is almost no relationship whatsoever in the way they sound? Without a +- db spec and some hint as the the measurement methods, those numbers are junk. The state of these audio specifications is so pathetic and deceptive that they are all but useless. I guess that is a subject to address at some future bloggery date.

Ok, so why do we want a flat response from the headphones anyway? And what is flat? Where do we measure flat? Though the frequency responses of these headphones are all over the map I am seeing some potential trends with both bass boost and double dip high frequency responses. Perhaps some manufacturers are imbedding a Fletcher-Munson response, the new standard ISO 226:2003 equal loudness contours or some other form of compensation?

Perhaps it is arbitrary or there is a lot of heavy thinking is going on? Well, well actually there are plenty of mind clustery debates about how to massage the response of headphones to be perceived in certain ways and sound in some form of corrected correct by ears in comparison to some other form of whatever. My friend Ferrit sent me this article which goes into some deep Stereophile depth of some of the whatevers they are trying to figure out. To get a taste of some of that take a gander at this:

http://www.stereophile.com/features/808head/index.html

Ha!, well I am sure that discussion can and will go on forever and never have a definitive winner of rightness, so lets take a slightly different approach and try and keep this a simple, repeatable practical path to a productive outcome.

I set out on this bloggery quest to find some currently manufactured headphones that are close to as accurate, loud and fidelic as the Sony CD3000's I have relied upon for the past decade or so, before they irreparably die. What I did not know when I started the testing is that when I run pink noise and place a measurement mic near my ear inside the CD3000 headphones, that I would see a response that is much flatter than many of the other headphones I am testing. Wow, that is so cool and makes things much easier as I have a simple logical starting point that makes a bit of logical sense.

Another really interesting aspect is that other highly regarded and popular live headphones such as the Sony MDR-V6, Sony MDR-7506, Denon AH D2000, Beyer 770, and Sennheiser HD280 would also measure much flatter responses than many of the headphones that are less favored by live engineers. So it appears that coincidentally many live engineers are naturally attracted to headphones with a response that shows up as relatively flat on my simple measurement method. Or perhaps, just perhaps, it is not a coincidence and the headphones that put out a fairly flat 'equal energy per octave' response are truly a useful reference point for live engineers while headphones with tailored responses are less than optimum.

So armed with the observations that popular live headphones show up fairly flat with my overly simple measurement system, I continue to listen and measure and narrow the field and bang out the rest that I have, first the sad goodbye's:

Oooh, the Grado SR60's are lower line Grado but since they are all open ear and these are the most popular of the line, I bought these just to hear them. They actually do sound quite nice and pretty much like you see below, smooth, a bit top heavy and not much in the sub lows.

May as well dump my old broken MDR 90's or whatever they are. Oooh, they look good and actually beat the spec but are discontinued, are on the ear types, look like tiny little toy headphones and wont get near loud enough to clear the next round. That said, it was sort of cool to find that that flat is not a pipe dream.

Here is my least favorite of the cans that almost meet the +- 4db 30hz to 12.5K spec. If it was not for the dips at 6.3 and 10K, they would make it at least looks wise. These Sony MDR-V600's show up pretty good but do not sound that great. Harsh top end and sub low weak. I am going to drop them as they are not quite up to par sound wise with the V6 and 7506's cans which I am also going to drop. We are not looking at re discovering the average run of the mill utility cans, we want something better.

The Sennheiser MD280's actually showed up better than the Sennheiser MD380's. The sub low on the 380's was more impressive but I really want to hear that smooth midrange. These do fall off a bit in the low mid, and the top end is a few db too much to the dark to make the spec. I have never owned these personally but, based what I see and hear their popularity with live engineers does make sense. But, again, going to drop them, looking for better.

These Equation Audio RP 21's were a pleasant surprise, never heard of them before this test. Yes, bass heavy and they have that spike up top, a bit out of spec but perhaps another option for something with more ULF and UHF than V6's in the $100 street price range that have a removable cable as well.

And now we step up to the true hot shot finalists, now we are talking! Check out these Beyer DT770 (not 770M yet as they are on their way still). They do have a bit of a rounding hump with 1K in the center that just barley puts them outside of the spec at we set at 10K. To be honest, I would like see more low end push and less HF droop, but oooh, can you say "nice cans!"

Take those Beyer's and bump the comfort level up a full notch, add in a the absolute most bad ass cable I have ever seen on headphones and you have these gorgeous Denon home Hi-Fi units. I still have some volume testing to do and yes, they do drop out of our spec at 1.6K due to the solid low end bump from the 50mm drivers that gives the D2000's a bit of that smiley curve home Hi-Fi sound. Ideally they would be a bit more edgy but these are really nice, well built and solid.

And now out of the 29 headphones I have spent the last month or so and maybe a hundred hours testing I have come across some that actually meet the huge gaping hole of sloppy loose +- 4 db from 30hz to 12.5K spec I set long before I knew how challenged the contenders would be. Really? Plus/minus 4db? Think about it, 10 db is twice as loud so our spec says that no frequency can be close to twice as loud as an other frequency. Anyway, these Ultrasone HFI-680 and HFI-780 headphones made it. Imagine my glee after all the time spent to actually have something that not only did not fail what seemed to be such an achievable goal but actually beats it by grabbing 25HZ as well..

And they do sound really good. Would love to see a removable cable, with a straight or coily option. P. S. I hate the coily headphone cables! Break away straight cables that unplug when you step on them are the way to go IMHO). Also of note is that these have offset drivers that do not shoot sound directly down your ear canal. They say in the literature that this is less intrusive to our beloved ears longevity. These babies sound tight, smooth, full range, and were the 'aaaah, I am not crazy' entrants that have made this worthwhile.

Note: I did an edit here.  I originally postsed the HFI 780's a second time in error.

Here is the CD3000 reference pair read out I am seeking to match or beat. Going back to them they do sound a ULF light now that I have the new exposures. The slightly thicker sound of the 680'sand 780's is welcomed though the CD3000's still sound more natural though a bit pushed high end wise now.

And while we are at it, I am going to drop the Sony MDR V6 and MDR 7506's from the running.

Though the Mighty Headphone Test is not done yet, these Ultrasone's have scored high enough to make the Dave Rat Recommends list. Plus I am impressed enough that maybe I should have Rat buy a pile of each and put together bloggery sale of them? What do ya think, anyone interested in a Mighty Top Dog Headphone Sale?

Model	Disqualifier	Listening notes	Comments	Status
AKG 271 MKII	Not Arrived		Still Waiting Arrival
Allen & Heath XONE XD-53	Not Arrived		Still Waiting Arrival
Apple iPod ear buds	Ear buds	ULF, LF--,	Bye bye, ear buds	Out
Audio Technica ATH W5000	Response	ULF-, HF-, UHF-	Smiley Curve	Out
Audio Technica ATH AD700	Open Ear	H-, UHF-	Clear, Very Flat	Out
Audio Technica PRO700	Response	LF++, HM-, H-	Bass heavy, powerful	Out
Beyer DT770	Not Arrived	ULF-, UHF+	Tonally Close
Denon AH-D2000	None yet	HF-	Tonally Close
Equation Audio RP-21	None yet	Smooth, HM-, UHF+	Removable straight cable
Equation Audio RP-22X	Response	Smooth, LF++	Removable coily cable,	Out
Grado SR60i	Open ear	ULF--, LF-, HF+	Low end light	Out
Koss ESP-950	Open ear	ULF-	Tonally Close, no isolation	Out
Koss MV1	Response	MID++	Cool no tangle coily cable	Voice optimized
Koss Portapro	Open Ear	LF+	Sound great!, small open ear	Bye Bye, open ear
Koss Pro4AAT	Response	ULF-, HF-, UHF--	Cool no tangle coily cable	Speech optimized
Pickering OA-3	Vintage low-fi	Yuck!	Never a contender	ouch!
Sennheiser HD 25-1 II	On ear		Still Waiting Arrival
Sennheiser HD 280 Pro	None yet	HF-	Tonally close, a bit dark	dull HF
Sennheiser HD 380 Pro	Response	HM--, HI-	Very smooth, LF clear	Hi-Fi but dull HF
Shure SRH-840	Response	LF++, UHF-	Removable cable	Out
Sony MDR-7506	Round 2	ULF-, UHF-	Tonally close, lacks ULF, UHF	Out
Sony MDR-7509HD	None yet	ULF-, M+, H-, UHF-	Midrange heavy, Smiley curve	Out
Sony MDR-90	On ear	ULF-	Tonally close, discontinued	Out
Sony MDR-CD3000	Discontinued	Ref	Ref
Sony MDR-V6	Round 2	ULF-, UHF-	Tonally close, Lack ULF, UHF	Out
Sony MDR-V600	None yet	ULF-, UHF-	Tonally close, harsh	Out
Sony MDR-XB700	Response	ULF++, LM+, UHF-	Too much LF	Out
Ultrasone HFI-450	Response	L+, M-, H-	Low heavy	Out
Ultrasone HFI-680	None yet	Smooth	Tonally Close
Ultrasone HFI-780	Response	UL+, H-	Tonally Close
Ultrasone PRO 900	Response	UL+, LM-, M-, HM-	Removable cable, Lacks mid	Smiley Curve

Next blog up, I am going to hit the top level units with some juice and see how they handle being on the back end of a power amp, bypassing those resistors they put on headphone outputs. This will allow us a look at the effect of the headphone resistor on the response, if any and I hopefully will be able to find any weaknesses in power handling.

Rock on and Happy Holidays!

Dave Rat

And on and on we go. I had no idea this would be so time consuming. I also had no idea it would be so interesting to hear how varied headphones can be in side by side comparisons..

So here are few more to gander at. Lets hack away a few more and find a keeper or two as well.

The Koss MV1's has a some dips and is tilted toward vocal inteligeability but we really need a smoother response.

Check out how flat these upper level Audio Technica ATH W5000 phones are until the 10 and 16db dips at 3.15K and 6.3K respectively. Good stuff but not quite good enough.

Ohh, and on these Ultrasone HFI-780 we have that double HF dip as well..

This HF dip pattern is showing up in several headphones. My guess is that some of the headphone designers are actually tailoring the responses a bit to account for the percieved loudness effects as described in the Fletcher Munson Curves to provide a sound that is desirable to listen to.

Here as well in the Sony MDR-7509HD cans we see an even more exagerated but similar pattern. I must admit this was a shocker. I really had high hopes for these. Especially with the 50mm drivers, I was hoping to hear something close the Sony CD3000's. The 7509's were both a bit dark and low-end light. Keep in mind I have not really burned in these cans and the burn in could warm the low end up a bit but it is highly that burn-in will fix this huge HF hole. Say bye bye 7509's. Darn!

Another EQ pattern is the 'smiley curve EQ' that tends to be pleasing to listen to and often described as Hi-Fi sounding. While this may be a desirable trait for listenability and offer a sound that is not harsh, for our purpose of having a live sound reference point, we want a flat response. The most 'Smiley Curve' sounding headphones I tested so far were the Ultrasone PRO 900's below:

And just to show another reference point, here is the graph of those same headphones on headphone.com

So while I have been hacking away at thinning I also have been finding some few with potential. Right off the bat it became apperent that the Sony 7506's are popular with live engineers for a good reason. Oooh, look at this: With the exception of the HF rolling off a bit early and a slight droop in the sub lows, these are darn good and flat.

And here is a look at the V6's. Again really flat and I hve heard that the V6 and 7506 have the same 40mm drivers or at least nearly identical and these RTA measurements are within 2 db of each other. Nice cans, not as nice as the CD3000's though. At least we not have a lower end of the spectrum of acceptability.

Now lets take a look at the measurements headphone.com got on the V-6's

Wow, a wide gentle hole at 250 a small peak at 320, gradual dip into slight peak at 3K, dip at 6.3K, peak near 10K and then rolling off from there into a 20K bounce that my RTA cant read.

One of the big hopefuls I had was the Shure SRH-840's

Unfortunately though, the Shure 840 demo ended before I figured out the analyzer snapshot idea and I had already sent the headphones back. But I did get a good amount of time listening to them. So, sorry about no RTA photo but I do have a read out from headphone.com that lines up very well with what I was hearing

Notice how well they emulate the response of the Sony V-6's from 500hz on up! Then notice the 6db bass boost. I can see it beeing a well liked response for DJ's and such but for our accurate live sound reference purposes that bass boost is going to be a considerable issue. In fact it looks like they grabbed the best parts of the Sony V6 and 7506 designs and added a removable cable, spare ear muffs and made a nice set of cans that fold up like the Sony's.

Due to the fact that these Audio Technica's AD700's are open ear design, they will not make it as live cans but they sure do have a nice response. A little low end light and looses top a bit early but they actually do meet our +-4 db spec we set for the CD3000's.

Check out these Koss ESP 950 Electrostatic headphones. Also within our specification though they are also an open ear design.

So, I am going to start putting the headphones that pass the frequency response specification in bold and strikethrough the headphones that for one reason or another will not make it to round 2.

Model	Disqualifier	Listening notes	Comments	Status
AKG 271 MKII	None yet
Allen & Heath XONE XD-53	None yet
Apple iPod ear buds	Ear buds	ULF---, LF--,		Bye bye, ear buds
Audio Technica ATH W5000	Response	ULF-, HF-, UHF-		Smiley Curve
Audio Technica ATH AD700	Open Ear	H-, UHF-	Clear	Very Flat
Audio Technica PRO700	Response	LF++, HM-, H-	Rotating ear cups, powerful	Bass heavy
Beyer DT770M	None yet
Denon AH-D2000	None yet
Equation Audio RP-21	None yet	Smooth, HM-, UHF+	Removable straight cable
Equation Audio RP-22X	Response	Smooth, LF++	Removable coily cable	Bass heavy
Grado SR60i	Open ear
Koss ESP-950	Open ear	ULF-	Tonally Close
Koss MV1	Response	MID++	Cool no tangle coily cable	Voice optimized
Koss Portapro	Open Ear	LF+	Sound great!, small open ear	Bye Bye, open ear
Koss Pro4AAT	Response	ULF-, HF-, UHF--	Cool no tangle coily cable	Speech optimized
Pickering OA-3	Vintage low-fi	Yuck!		ouch!
Sennheiser HD 25-1 II	On ear
Sennheiser HD 280 Pro	None yet	HF-	Tonally close
Sennheiser HD 380 Pro	Response	HM--, HI-	Very smooth, LF clear	Hi-Fi but dull HF
Shure SRH-840	Response	LF++, UHF-	Removable cable
Sony MDR-7506	Round 2	ULF-, UHF-	Tonally close
Sony MDR-7509HD	None yet	ULF-, M+, H-, UHF-	Midrange heavy	Smiley Curve
Sony MDR-90	On ear	ULF-	Tonally close
Sony MDR-CD3000	Discontinued	Ref	Ref
Sony MDR-V6	Round 2	ULF-, UHF-	Tonally close
Sony MDR-V600	None yet	ULF-, UHF-	Tonally close, harsh
Sony MDR-XB700	Response	ULF++, LM+, UHF-	Too much LF	Bye bye too bassey
Ultrasone HFI-450	Response	L+, M-, H-	Low heavy
Ultrasone HFI-680	None yet	Smooth	Tonally Close
Ultrasone HFI-780	Response	UL+, H-	Low heavy
Ultrasone PRO 900	Response	UL+, LM-, M-, HM-	Removable cable, Lacks mid	Smiley Curve

Dave Rat

It was recommended to me that I get a second reference point other than my own head to check for any response anomalies. Great idea. Again, super simple, I just stuck the mic inside and held the CD3000's around one of the cases that came wit the Ultrasone 900's. As you can see it is slightly different than the 'on my head reading but still darn close. As with all the readings there is a slight variation with moving the mic a bit and ear pad pressure, but all the reading stay surprisingly close and consistent for each pair of headphones. I tried this with several other pairs and they all too were consistent with the reading while on my head.

So lets have some fun and start elimination round #1 getting rid of some now that I have a good solid selection to pick from. Lets get the reference CD3000's up.

Ok, if you cant read the #'s here they are. I am putting the frequencies with lines down to them in bold

25, 32, 40, 50, 63, 80, 100, 125, 160, 200, 250, 315, 400, 500, 630, 800, 1K, 1.25K, 1.6K, 2K, 2.5K, 3.15K, 4K, 5K, 6.3K, 8K, 10K, 12K, 16K, 20K

There is 8 db between the horizontal lines (2 db per led) so as you can see this reads that the CD3000's are within an 8db range from 25hz to 12.K. Since my setup most likely is not very accurate beyond 12.5K, and for live sound EQ it is not very critical up there as we lose most of that super high stuff to air loss anyway, I am not going worry about 16K and 20K. So as our spec, we can say that we are looking for headphones equal to or better than a +- 4db 25 to 12.5K using my crude but simple measurement system.

First say bye bye to Apple ear buds as clearly they will not work for the desired live sound purpose but they are fairly flat from 125 to 12.5K

No go on the Sony XB700's because they are just not going to cut it the cables too short and their response is way off with the bass boost, big hole at 630-800 and rolling off highs.

Yikes, check out the response of the Pickering vintage OA-3 phones!

These open ear Koss PortaPro open ear phones actually sound quite good, lots of low end and I was duly impressed by the sound versus size and cost. That said, I think I want them for my portable player but they just wont work for live shows.

The Audio Technica Pro 700's had strong low end power but were midrange heavy and lacked a top end.

The extra bass Equation Audio RP22X were smoother sounding but as expected, they were low end heavy. But hey, they are the extended bass version. I think this may be a good DJ headphone at a reasonable price. Plus the 1/4 turn removable cable is a nice feature.

And here drops the first one of the big boys. This was a real surprise for me but what I heard and what I see lined up. Say bye bye to the comfy, nice iso, neatly folding Sennheiser HD380 PRO's. Deep but a bit loose sounding low end, mids a bit subdued and though they sound Hi-Fi, the holes in the upper ranges just pulled all the clarity out. They actually sounded a little similar to the RP22X but with 20 db down at 6.3K and 12 db down at 2.5K, I had to drop them from the list.

It was fun to put on the Koss 4AA cans and brought back fond memories. These durable things have a solid tight fit and some heft and though I do not recommend them for live monitoring cans they do seem optimized for speech intelligibility, so they would make good utility cans in high volume environments.

Finally for today an entry from Ultrasone, the HFI 450 pair show a smooth but gradual roll off towards the HF.

And the culling of the 'heard' has just begun. There are plenty more and some surprises ahead!

Model	Disqualifier	Listening notes	Comments	Status
AKG 271 MKII	None yet
Allen & Heath XONE XD-53	None yet
Apple iPod ear buds	Ear buds	ULF---, LF--,		Bye bye, ear buds
Audio Technica ATH W5000	None yet	ULF-, HF-, UHF-
Audio Technica ATH AD700	Open Ear	H-, UHF-	Clear
Audio Technica PRO700	Response	LF++, HM-, H-	Rotating ear cups, powerful	Bass heavy
Beyer DT770M	None yet
Denon AH-D2000	None yet
Equation Audio RP-21	None yet	Smooth, HM-, UHF+	Removable straight cable
Equation Audio RP-22X	Response	Smooth, LF++	Removable coily cable	Bass heavy
Grado SR60i	Open ear
Koss ESP-950	Open ear	ULF-	Tonally Close
Koss MV1	None yet	MID++	Cool no tangle coily cable
Koss Portapro	Open Ear	LF+	Sound great!, small open ear	Bye Bye, open ear
Koss Pro4AAT	Response	ULF-, HF-, UHF--	Cool no tangle coily cable	Speech optimized
Pickering OA-3	vintage low-fi	Yuck!		Bye bye poor response
Sennheiser HD 25-1 II	On ear
Sennheiser HD 280 Pro	None yet	HF-	Tonally close
Sennheiser HD 380 Pro	Response	HM--, HI-	Very smooth, LF clear	Hi-Fi but dull HF
Shure SRH-840	None yet	LF++, UHF-	Removable cable
Sony MDR-7506	None yet	ULF-, UHF-	Tonally close
Sony MDR-7509HD	None yet	ULF-, M+, H-, UHF-	Midrange heavy
Sony MDR-90	On ear	ULF-	Tonally close
Sony MDR-CD3000	Discontinued	Ref	Ref
Sony MDR-V6	None yet	ULF-, UHF-	Tonally close
Sony MDR-V600	None yet	ULF-, UHF-	Tonally close, harsh
Sony MDR-XB700	Response	ULF++, LM+, UHF-	Too much LF	Bye bye too bassey
Ultrasone HFI-450	None yet	L+, M-, H-	Low heavy
Ultrasone HFI-680	None yet	Smooth	Tonally Close
Ultrasone HFI-780	None yet	UL+, H-	Low heavy
Ultrasone PRO 900	None yet	UL+, LM-, M-, HM-	Removable cable, Lacks mid

Alright, that's it for today.

Dave Rat

The listening test. Since the goal here is to find some headphones that are flat and accurate for live engineers to use as a reference point, lets consider a few factors.

1) Most sound live sound consoles have fairly generic headphone amps so for me to test with some fancy headphone amp would not make much sense.

2) These headphones should not be biased toward any particular music type so the type of music should not be relevant other than purely to highlight issues.

3) Hopefully the only aspect that involves my opinion really is the decision to use the CD3000 and the assumption that the CD3000's are a flat and accurate reference. Though with all the testing I have done on speakers over the years and listening and EQ'ing systems to flat, I am quite confident that the CD3000's are a fairly accurate reference point. Or at least the most accurate I have found yet.

So, what I am doing for the listening phase is is purely comparative. Just out of ease and familiarity I am primarily using a record player as the music source and lackluster stereo receiver. I will shoot a pic for next blog post. This allows me to easily replay the same part of a song and the clicks an pops of my old records allows me to hear how the headphones deal with those sharp spike dynamics. I started out with various tracks from Pink Floyd The Wall and Wish You Were Here albums. Today I am using Van Halen's first record. Did ya know that Jamie's crying, you can't have any pudding and you are gonna make it if you try they're gonna love you. I also give them a listen on an iPod where I have been using Ween, Butthole Surfers (good sub lows) and Why Don't You Do Right from the Roger Rabbit soundtrack (Amy Irving vocals). All that said, what I am really finding is that it makes very little difference what I use for music. The boomy headphones are boomy everywhere on everything. The dull phones are dull on everything and so on. Their was one helpful thing I found for sorting them though. I have a few different phono cartridges for my turntable. One is quite dull sounding and another is very crisp and bright. I find that if I use the dull sounding cartridge it really helps me hear variations in the high mid and higher frequencies between various headphones. Whereas with the tonally bright cartridge it is more difficult to discern, as the variations are masked a bit.

So all I do is play a song, put on the CD3000's, then swap to the headphones I am comparing, go back and forth a few times and take some notes. Really simple and the differences are tending to be so readily noticeable and clear cut that it is really a no brainer. As soon as I put them on, boom, these lack lows, boom, these suck the vocals out, boom highs are dull and so on.

Below is the current list of what is on the headphone test plate. Most of these I already have started evaluating while some are still on their way to me. I am not against adding more but having started, I can tell you that unless the headphones that get recommended are extraordinary and sound bright and clear and they have have super smooth low end without boominess, they will not make it very far. So far my testing is showing that many highly regarded favorites have response curves that make them less than optimum as reference headphones. Yes, many of them do sound quite good but I am finding that the pleasing sound comes from either a gently sloping response, a bass boost and/or a notch in the 1K to 5K region. All of which make those headphones non-ideal reference points.

Model	Disqualifier	Listening notes	Comments	Status
AKG 271 MKII	None yet	In transit
Allen & Heath XONE XD-53	None yet	In transit
Apple iPod ear buds	Ear buds	ULF---, LF--,
Audio Technica ATH W5000	None yet	ULF-, HF-, UHF-
Audio Technica ATH AD700	Open Ear	H-, UHF-	Clear
Audio Technica PRO700	None yet	LF++, HM-, H-	Rotating ear cups, powerful
Beyer DT770M	None yet	In transit
Denon AH-D2000	None yet	In transit
Equation Audio RP-21	None yet	Smooth, HM-, UHF+	Removable straight cable
Equation Audio RP-22X	None yet	Smooth, LF++	Removable coily cable
Grado SR60i	Open ear	In transit
Koss ESP-950	Open ear	ULF-	Tonally Close
Koss MV1	None yet	MID++	Cool no tangle coily cable
Koss Portapro	Open Ear	LF+
Koss Pro4AAT	None yet	ULF-, HF-, UHF--	Cool no tangle coily cable
Pickering OA-3	vintage low-fi	Yuck!
Sennheiser HD 25-1 II	On ear	In transit
Sennheiser HD 280 Pro	None yet	HF-	Tonally close
Sennheiser HD 380 Pro	None yet	HM--, HI-	Very smooth, LF clear
Shure SRH-840	None yet	LF++, UHF-	Removable cable
Sony MDR-7506	None yet	ULF-, UHF-	Tonally close
Sony MDR-7509HD	None yet	ULF-, M+, H-, UHF-
Sony MDR-90	On ear	ULF-	Tonally close
Sony MDR-CD3000	Discontinued	Ref	Ref
Sony MDR-V6	None yet	ULF-, UHF-	Tonally close
Sony MDR-V600	None yet	ULF-, UHF-	Tonally close, harsh
Sony MDR-XB700	None yet	ULF++, LM+, UHF-	Too much LF
Ultrasone HFI-450	None yet	In transit
Ultrasone HFI-780	None yet	In transit
Ultrasone PRO 900	None yet	In transit

Code:

• ULF - Ultra low Frequencies, like 20 to 40 or so.
• LF - Low frequencies, like 60 to 150 or so.
• LM - Low mid, like 150 to 400 or so
• M - Mids, like 400 to 1000 or so
• HM - High mid, like 1000 to 3000 or so
• H - Highs, like 3000 to 6000 or so
• UHF - Ultra High Frequencies, like 8000 to 20,000
• The more "+" means the more there is. he more "-" means the less there is.

So that is where listening has taken me so far. I also have devised a stupid simple way to get a rough frequency response measurement for comparative purposes that seems to work surprisingly well! I was thinking, how can I measure what my ear hears? I could:

A) Build a dummy head with a fake ear, an ear canal and then spend endless hours refining and testing to see if it is accurate and try and eliminate any issues. I then could go into depth trying to prove the credibility of my measurement method.

Or

B) I could put the headphones on my own humanly head, shove a measurement mic so it pick up the sound right where is goes in my ear and take some actual readings of what is my ear hears.

Hmmm, I am going to roll with the "B" method and see what happens. Plus, plan B is easily repeatable by anyone who has Smaart, and RTA or any other audio measurement system thus allowing anyone to easily check the results of what I measure on their own gear. Cool! So I am going to run this whole deal old school and simple, the way I like it.

But before we move on, in my e-wanderings I found this cool web site:

http://www.headphone.com/learning-center/build-a-graph.php?graphID[0]=1513&graphID[1]=533&graphID[2]=913&graphID[3]=&graphType=0&buttonSelection=Compare+Headphones

They have already done frequency response curves on quite a few of the headphones I am looking at and the graphs results somewhat match what I am actually hearing. You can actually pull up and overlay graphs. I spent a while there and compared every headphone they have graphs for to the V6. Cool.

Burn In. A few people have brought up burn-in. Burn-in refers to a phenomenon where the sound of a speaker changes over time and that the stable response characteristic is not reached until a transducer is used for some or many hours. I have no doubt the burn-in effects the response of headphones and speakers. We see it all the time with subwoofers where they become floppy and tune at a lower frequency over time. That said, the typical and logical result of burn-in is a slight lowering of the low end tuning frequency as the mechanical compliance loosens. I can tell you right now, there is nothing slight about the differences between the various headphones I am evaluating. The variations are drastic, huge, monumental and tremendous. Giant 5db multi-octave wide holes and peaks. If a pair of headphones is going to have a shift of octave wide 5 db hole or peak due to burn-in, it deserves to be eliminated anyway. Any cans that are doing well, will keep getting tested and naturally burn-in through testing. So say bye bye to burn-in concerns as a relevant factor in this testing.

So I turn on some pink noise, run it through the CD3000 headphones and slide the measurement mic close to where sound enters my ear and...

This is set on 2db scale so the horizontal lines represent 8 db. So here is the response of the reference CD3000 pair of headphones on my humanly head. Looks like + or - 5 db from 25 to 12.5K. Note, I do not think my mic or other gear is grabbing the frequencies above 12k very well, but that is the least of our worries. And after years and years of using these headphones to finally see their response and have them come up relatively flat was quite exciting. Wait till you see what the other cans look like!

Here are the Sony XB 700's and check out that nearly 3 octave, 12 db deep hole from 315 to 1.6K followed by a 6db/octave roll off. That looks like it will sound like standing outside a car cranking stereo with the doors closed, and it does!

Here is how the iPod earbuds showed up. I could not get the mic between my ear and the bud so I just balanced the bud on the mic. These actually should get more low end when in your ear.

Ooooh, look, fairly flat with a gradual roll off below 100 Hz and a smooth hole centered at 2K. That actually looks like it would sound pretty good.

As far as the accuracy of the measurements? Well, first of all, as I move the mic around it really does not change that much. Secondly, I do spend a bit of time trying to get the best reading I can for each headphones. Thirdly, the variations between the differing headphones are so drastic, that a bit of error in the measurement is a low concern. Finally, it is reassuring to my measurements have some parallels to measurements done by headphone.com but more importantly, the RTA readout really does look like what I am hearing so my confidence is quite high.

OK, enough for now, I have lots more and many surprises to come as I will save the good stuff for later!

Dave Rat

PS, I found this while wandering Ebay looking to buy a pair of Grado headphones to test

OMFG! $1100 for a pair of 3 foot long phono cables! This is a real auction seeking a real moron.

The Mighty Headphone Quest Well this is really turning into a research project, fun stuff! Ok so here is the plan, not unlike how I design the Orgasmatron's (Vortex), Double Hung PA, processor settings for MicroWedge and most things I do, I will start with trying to form a logical plan, make human observations and get as far as I can without diving into test gear, then try and create a way to measure by using electronics and finally go back and see if the technical measurements align with the human observations . I will do my best to be objective. There are many diverse applications that headphones can be used for ranging from casual listening, utilitarian, striving for perfection, max volume, max low frequency, max isolation and on and on. I even found:

http://www.auditory.org/mhonarc/2004/msg00847.html

where headphones must be completely non magnetic and are optimised to be used to mask the noise and provide music to humans while getting an MRI scan. So like with so many things in life, it is about finding and using the right tool for the job. The primary focus of this evaluation to locate headphones that are optimised to act as a quality reference point for live sound engineers. So my plan is:

#1 - Listen wit my ears. I have big pile of cans and I am listening to music and switching between the various pairs while taking some notes of things I notice. Meanwhile I keep referring back the Sony CD3000's to keep my bearings straight.

#2 - Sort them by ear. I am sorting the headphones based on how close they sound to the reference pair..

#3 - Check credibility with test gear. Then I will try and figure out a way to measure the headphone using and see if what I heard and sorted has correlations with what I measure.

#4 Summarize. I will hopefully have a recommendation for one or more pairs.

So far there I am dealing with steps #1 and #2 and just begriming to plan out step #3. What I am finding is really interesting. The sound of headphones varies so vastly that it is truly incredible that they can even be listed with remotely similar specifications as there is almost no similarity in the way they sound.

As I listen I am sorting into some categories

A) DJ Sound. These all have some sort of big bass boost going on for listeners and DJ's that seek lots of extra low end.

B) Sloping Response. The lows are louder with a gradual slope downward towards the highs. This is actually a very listenable and common response and I like to tune sound systems this way. For example, with the EAW MicroWedge's, the Grey and Red processor settings are sloping responses.

C) Flat Sound. This is what I consider the CD3000's to exhibit though I have yet to test them on an analyzer. By comparison the sound is a bit bright but not lacking in low end. This would be the equivalent of the MicroWedge 'White' processor setting.

**** The Goal ****

The goal of this quest is to find the optimum live sound reference headphone. A portable accurate head worn sound system to act as a constant reference point. More specifically, a headphone that sounds as flat as possible.

Having a perfectly flat audible reference point allows the sound engineer to make informed auditory decisions by comparative reference. Additionally it reduces dependence on test equipment. By using comparative reference you can factor out the natural hearing fluctuations caused by plane flights, illness, age or long term exposure to high volume sound. Studio engineers have finely tuned and calibrated studio monitors in an optimum acoustic environment as a reference point, for us live engineers, a pair of headphones is our best bet.

Ideally you should be able to put on the headphones, listen to a CD, take them off, turn the CD up in the sound system and equalize the sound system to sound exactly like the headphones, therefore the sound system would be equalized to flat. I.E. - copy the sound of the headphones to the PA and have the CD sound as close as possible to the way it sounded in the recording studio.

Same thing with pink noise. Ideally you should be able to listen to pink noise in the headphones, take them off, listen to pink noise in the sound system, EQ the sound system by ear to sound like the headphones and the system should be flat. Then you ideally should be able to use an RTA or other measurement device, measure the pink noise coming from the sound system and confirm the system is truly eq'ed flat.

So that means that any aberration from flat the headphones exhibit will result in system EQ errors. For example: If you use headphones with extra bass, then the CD or pink noise in the headphones would sound low-end heavy. You would then be inspired to add extra low end to the sound system when matching the headphone sound to the PA sound. The low end heavy PA EQ would now cause several issues. When you EQ your mic channels you will tend to cut low end to compensate for the bass heavy PA. Any stereo recordings pulled pre system EQ will now be overly bright sounding. Imagine if recording studio monitors had a huge bass boost. Every recording coming out of that place would be super thin sounding. The goal is to have the console mix be flat before entering the system EQ's.

Note:

The console channel EQ's should make the mic/instrument combo sound correct.

The house system EQ should make the system/venue combo sound correct.

The system processor EQ should make the loudspeaker/enclosure combo sound correct.

Hence we seek a highly specific headphone. Flat flat and flat. Loud is good, wide response is good,low end is good, isolation is good, but first and foremost, flat. There are many amazing headphones out there that have numerous very desirable assets and people that swear by them. I have already begun testing and I am already finding that many of the popular live headphones are not ideal reference points. And also, at least one set of popular headphones make a quite good reference point.

So lets get some of the easier stuff out of the way and thin the herd a bit by starting with some I was considering that are marketed as DJ headphones:

Say Bye Bye to potential contenders:

Stanton DJ Pro-3000 - 50mm, 30 ohms, 106 db/mw, 20-20K

Pioneer HDJ-2000 - $349 List, $250 Street, 50mm, 36 ohms, 107 db/mw, 3500mw, 5-30K

But do not be sad as I am adding some that have been recommended to the list as well:

And due to requests, research and stuff laying around my house, say hello to:

Sennheiser HD 25-1 II - Yes they are 'over the ear' but popularity with sound engineers and numerous requests have inspired me to include them.

Denon AH-D2000 - Another requested headphone and with the over the ear design and large drivers it seemed worth testing

Pickering OA-3 - These are 1975 era open ear phones that I had laying around the house. I will toss them in the test mix just to give an idea of what people used to consider listenable. Oh, you really should check out the Pickering link I used and browse around.

Apple iPod ear buds - These are the standard ear buds that come with iPods. I figure that since these are most likely the most listened to things out there, may as well include them as a reference as well,

Sony MDR-90 - (I think) - I can not read the model # as it has worn off but these are some over the ear headphones that were my favourites before I found the CD3000's. They sounded great and though the mount broke, I still have them so why not add them to the test? I will shoot a epic and maybe someone will recognize them.

Beyer DT770M - Demo requested and it looks like they are coming.

AKG 271 MKII - Demo on it's way.

Equation Audio RP-22X - These are bass boost versions of the RP-21. Though I am not looking for bass boost, I may as well listen as they were kind enough to send me demo's.

Allen & Heath XONE XD-53 - $249 List, $199 Street, 53mm drivers, 36 ohms, 105 db/mw (1K), 350 mw, 5-33K. Very cool. I guess the blog gets around and Allen & Heath are sending me a pair to evaluate.

Ultrasone - HFI-780 - A third pair of ultrasone's have been added.

And finally there are two more on the potential list now

Ultraphones - These are high isolation headphones with Sony 7506 drivers.

David Clark Model 10S-DC - Which are also high isolation headphones.

Lastly for today's installment I want to thank the people and manufacturers that are helping me make this happen. Thank you Daniella and John Karr from Rat for putting up with my endless requests for more product!

Thank you Darlene from Audio Technica for going out of your way to expedite the request.

Thank you to all at Sennheiser as you always take care of us Rats.

Thank you Cynthia, Haley and Phil for spending time chatting with me and arranging the Koss headphones. Oh, check out http://www.koss.com/koss/kossweb.nsf/kmuseum?openform

Thank you Brian and Randy for rocking together the Ultrasone cans.

Thank you Equation Sound for hooking me up.

Thank you Beyer and AKG for sending out the phones.

Thank you Shure for the 840 demo unit.

Some of these companies Rat does quite a bit of business with while others do not know me or Rat well but were gracious warm and more than happy to assist.

Oh and can I tell you how cool it is to be knee deep in a pile awesome headphones! I am so a kid in a candy store!

Dave Rat

For over a decade now I have sworn by my now discontinued Sony MDR-CD3000 headphones as my trusty live sound reference point. When I wrote an article stressing the importance of having high quality live sound cans I failed to mention viable options for the sound engineer readers to acquire.

When Hearing Starts to Drift

So, the plan is to get my hands on a nice collection of top brand headphones, give them a listen while using the CD3000's as a reference and find something similar or hopefully superior. So the rules of the game at this point are:

Closed Back- The headphones I seek should be closed back. Seems simple enough but the fact is that many of the high end headphones are currently open back. This is because the smallish headphone sound chambers tends to choke off the lows and cause some negative sonic artifacts. Porting the chamber to the outside world reduces isolation and porting to the inside the muff area can add low and low mid resonance. Regardless, for us live humans, we need the sound isolation though I am not holding high levels of isolation to be imperative as that would overly narrow the options and also eliminate my CD3000 reference phone. So as long as the headphones get fairly loud, preferably rock concert levels and offer a reasonable attenuation of the outside world, I will include them.

Around the Ear - Theoretically, on-the-ear designs could work but the added isolation of an around-the-ear (circumaural) design plus the typically larger sizes of the transducers in over-the-ear headphones, inspired me to narrow the field and a bit. The in-ear designs can offer excellent isolation and possibly are capable of enough fidelity and volume, though I have never heard any that sound amazing, but for a sound engineer's reference point, we do not have the time to be shoving things in and out of our ears mid rock show.

No Internal Electronics - I have so far bypassed all the noise canceling, electrostatic and other pre amplified headphones because I am skeptical of the added layer of complexity, dead battery issues and other artifacts. The last thing we live sound humans need is the noise canceling circuit overloading from the rock show or some strange sound added. That said, I am not against considering electrostatics if I am able to get my hands on some.

Size does not Matter - Or more specifically, bigger is better. I am really looking for a 'Head PA.' A cranial sound reinforcement system capable of accurately reproducing dynamics, wide bandwidth and high level sound. It is not like we will be jogging with these things.

High Power/Volume - In my experience headphones blow out fairly often when used for live sound, mainly because I inevitably forget to turn down the headphone volume when I set them down. I am looking for a pair that handles some juice. I have found several models that are rated at 3000 mw.

Hard Clean Sound - There are two differing approaches to loudspeaker and headphone design. The home hi-fi approach where the goal is to gloss the musical flaws and present the listener with a pleasing and enjoyable sound. The other is the studio monitor approach where the goal is to expose all the flaws in a harsh and accurate light so they can be addressed. I am looking for a pair of cans that just sounds like the damn instrument I am trying to listen to.

Cost is Irrelevant - Well, it's not irrelevant, but I did not put a cost restriction on the units I am testing.

Minimize my Opinion - Since sound quality is highly subjective I will try an reduce the effect of my opinion on the selection process. All the headphones will be tested in comparison to the Sony MDR-CD3000 pair I have. My goal is to try and match or beat the sound quality, volume and frequency response of the 3000's.

So lets take a look at the reference pair and growing list of contenders. I have listed a few specs. The street prices are just a quick low mid estimate and I tried to be realistic and avoided the super cheap questionable vendors. The list price is the same as MSRP, I just used what ever I found. It is quite an endeavour getting my hands on all these cans. Fortunately several manufacturers have been so kind as to send me demo's plus I was able to raid Rat Sound's headphone stock. A few I actually purchased and some I am still on the fence about whether to to try and get them in the mix. So I listed in parenthesis the source/status.

The Contenders (so far)

Sony MDR-CD3000 - $699 List, Discontinued, 32 ohms, 104 db/mw, 500mw, 20-20K (Dave Rat, reference)

Sony MDR-V6 - $109.99 List, $80 Street, 63 ohms, 40mm drivers, 106 db/mw, 1000mw, 5-30K (Rat)

Sony MDR-7506 - $130 List, $99 Street, 63 ohms, 40mm drivers, 106 db/mw, 1000mw, 10-20K (Rat)

Sony MDR-7509HD - $265 List, $189 Street, 50mm drivers, 24 ohms, 107 db/mw, 3000mw, 5-80K (purchased)

Sony MDR-XB700 - $130 List, $80 Street50mm drivers, 24 ohms, 107 db/mw, 3000mw, 3-28K (purchased because they look so cool!)

Sony MDR-V600 - $99 List, $70 Street, 40mm drivers, 45 ohms, 106 db/mw, 1000mw, 5-30K (Rat)

Sennheiser HD 280 Pro - $149 List, $99 Street, 64 ohms, 102 dB (IEC 268-7), 500mw, 8-25K (Rat)

Sennheiser HD 380 Pro - $299 List, $199 Street, 54 ohms, 110 db (1Khz 1 Vrms), 500mw, 8-27K (demo)

Shure SRH-840 $250 List, $199 Street, 40mm drivers, 44 ohms, 102 db/mw, 1000mw, 5-25K (demo)

Audio Technica PRO700 - $279, $115 Street, 53mm drivers, 36 ohms, 105 dB/mW at 1 kHz, 3500mw, 5-33K (demo)

Audio Technica ATH W5000 - $1699 List, $699, Street, 53mm drivers, 40 ohms, 102 db/mw, 2000mw, 5-45K (demo)

Ultrasone HFI-450 - $119 List, $99 Street, 40mm, 32 ohms, 96 db, (unspecified), 20-20K (demo)

Ultrasone PRO 900 - $599 List, $549 Street, 40mm, 40 ohms, 96 (unspecified), 6-42K (demo)

Koss ESP-950 - $999 List, $699 Street, electrostatic, 100K ohms, 104 db/mw, 8-35K (demo)

Koss Pro4AAT $99 List, $69 Street, 250 ohms, 95 db/mw, 10-25K (demo)

Koss MV1 - $179 List, $119 Street, 250 ohms, 98 db/mw, 10-25K (demo)

And there are few more headphones I may get into the mix.

Beyer DT770M - $289 List, $289 Street, 80 ohms, 105 db ( IEC 60268-7 ), 100 mw, 5-30K (demo requested)

AKG 271 MKII - $299 List, $199 Street, 55 ohms, 91 db/mw, 200mw, 16-28K (demo requested)

Equation Audio RP-21- $149 List, $90 Street, 32 ohms, 100db ?, 10-22K (demo requested)

Allen & Heath XONE XD-53 - $249 List, $199 Street, 53mm drivers, 36 ohms, 105 db/mw (1K), 350 mw, 5-33K (undecided)

Phiaton PS-500 - $299 List. $250, Street, 50mm, 32 ohms, 102 db(?) (undecided)

Stanton DJ Pro-3000 - 50mm, 30 ohms, 106 db/mw, 20-20K (undecided)

Pioneer HDJ-2000 - $349 List, $250 Street, 50mm, 36 ohms, 107 db/mw, 3500mw, 5-30K (undecided)

Well alright. That will keep me busy for a while. Hey, if I missed any worthy headphones as contenders and you have suggestions or you feel any of the ones I am undecided about really need to be tested, let me know. Also, if you are with a company or have connections to line up some demo cans that should be included, that would be great too.

I have started listening and testing and WOW! The diversity is mind boggling! So far there is absolutely no correlation between the frequency spec's, cost and the way these things sound. It is like the old school wild west of sonic lawlessness!

Dave Rat