Dave Rat - Roadies in the Midst

Jones Beach. I remember the first time I ever did a show here was Lollapalooza 1992, the first of two shows went on with out a hitch but for the second show our little friend Hurricane Andrew decided to drop by for a visit and lay a category 5 wind and rainstorm on top of all the wires, speakers, lights and humans. Talk about torrential downpour! I have some old video of it somewhere that have been meaning to post. Pretty intense seeing the lights and PA swinging and mashing into each other. Big chunks of gear blowing over into foot deep puddles flowing in a cascading waterfall off the stage while sideways rain blows away tents and any attempt to protect the not so thirsty gear.

So I have settled into two subwoofer designs and hope to be able to flow one or the other into the rest of the tour gigs. The Vortex or Orgasmatron setup gives me a bit more control over coverage and allows me to disperse low end over a very wide area. Also the Vortex gives me excellent rejection on stage and directly behind the subs. Our other setup which I guess I will call the Slotfire Cannon. It is similar to the Sub Cannons I used to fire to the sides of the arena's on Peppers tour but they take up less depth, are more efficient and offer a bit better control. Being four feet deep and about 14 feet wide, the Slotfire should be able to drop into most sheds fairly easily. The has quite good control over widening coverage but offers very little cancellation behind the arrays. So for venues that have a wall behind the subs, the Slotfire is a good way to go. Conversely the Vortex work best if there is open space behind them.

Perhaps you noticed we spun the Vortex (Orgasmatrons) 45 degrees? Ahh for this gig it gave us better sighlines, so therfore better placement downstage and a bit more control. So here is the basics of the Slotfire setup as done morning of the show;

The theory on the Slotfire is to space two acoustic centers at 1/3 of a wavelength of the desired center frequency. For this I chose 45hz due to the sub design and program material I am sending, so about 8.5 feet or so. Then if I delay the outside acoustic source by 3.6 to 7.2, I gain a tremendous amount of control to steer the low end to the outside. Zero time delay gives me a figure 8 pattern, which I do not need as I want to steer outward and reduce power alley. Here are some simple predictions for one side

A 3.6 ms delay is 1/6 wavelength at 45 hz so if you apply that to the outside subs and add that to the 1/3 wavelength physical spacing, we get that 1/2 wavelength virtual spacing that gives nice cancellation towards the stage and steers low frequencies outward

And as we increase delay further it steers more outward.

So super simply I can control how wide the coverage is while reducing power alley, just by adding delay.

The trick though to get this all to work efficiently is to create two nice LF point sources with the subs. Ahhh, and that is where the super cool part comes. Because to get an 8.5 spacing of acoustic centers with 4 foot wide boxes means the stacks would only be 6" apart. Basically one big wall with some time delay mushing it up, which is lame and boooring! So what I did was to point the subs at each other with 12" spacing. Now I have two very clean 12" wide acoustic centers to work with. And wow! This setup kicks butt!

The sound of this setup is really solid and powerful, more so than the Vortex. But, keep in mind, the Vortex offers more control. If I setup the Slotfire in an arena, poor Steve and everyone else behind the subs would be completely obliterated. Never forget that the key is using the right tool for the right job.

Haa! I got to be the guinea pig for the flying drum riser test drive!

I think this was Montreal

May as well start introducing the awesome Rat crew out here putting up with my antics. Meet Jim, also known as Ice, not sure why but hey, nicknames rule. He is my FOH tech and the one who directly gets my world dialed in. I do put a lot responsibility on my tech, and really appreciate him keeping it together. Oh, Nick the Fly was out here but he went back to home world and was the front end guy that helped me get my wacky designs all dialed in.

This is Robert, he rocks the stage wire world

Scott Sugden (top left) came out for a few days to hang with us and Roz (working with Scott) is our laser room measuring K1 system design guru now that Nick is gone.

Manny is out here too promoting corn chips mainly but I think he does some PA setting up as well.

Re ran the orgasmatrons at Jones Beach. Good news is Mark Hoppus went inside during the show. Bad news is he tripped over the strap that holds them together and fell inside with his bass on mid show. Fortunately he did the party roll and landed on his back and seemed ok.

Hello Me

Jessica is our wonderful production assist and awesome to work with.

May as well toss some show shots in the mix

After the gig, we Blink fans all hang out waiting for the band.

Not really related but some say Pigeons are like flying rats, so I figured I would toss some props out to our flighty friend here.

Okey dokey artichokey. See ya soon for more brain twisting adventures soon.

Dave Rat

Toronto and back in a shed again. Well, last night in Montreal was quite amazing, packed house of pure exuberance. Truly a fun show that finished off a pretty rough day. Long bus rides, border crossing into Canada and we lost a roller. So there we are parked with whizzing traffic roadside in the dark wee hours. Two busses dividing up the delirious human cargo of the third. Passports, blankets and pillows staggering through the gravel. Losing four hours on the front end of load in makes for a push to get the show up and the show must go up and go up safely. Other than one of the crew from the dead bus forgetting his shoes on the broken bus, it went well enough.

Getting in the familiar groove. Each day I remove more console labels, and have been mixing in full darkness for the last several shows. It takes me a few shows to learn the setup and this is my first tour on an XL4 console, so I embarrassingly had to light and label, I have been giving refining my mix strategy for this tour.

I am looking for an almost 'cartoony' sound, not sloppy, just a bit saturated. A little too much of this and then a little too much of that. And vocals, lots of strong clean distinct vocals more on top than usual. Every word spoken between songs is as much the show as the songs, I really want clear defined and 'understand every word' intelligibly. All leading up to a lot too much of everything for Travis' no holds barred flying spinning drum solo, at which point I get to unleash the full power of this K1 system. Fun stuff!

Also, unlike Peppers tour, real estate for the mix position is not an issue so we have sprawled out into messy little mini city.

Our support acts keep changing throughout the tour but Panic at the Disco was around for bit and will be back

Fall Out Boy hangs with us for a while

and Chester French

And Hey, may as well feature a roadie of the day. Meet Daniel, also sometimes known as Satan. If you let your guard down you may as well lay down cause its all over if he catches it. Oh, and he is the awesome drum tech that gets Travis' world running smooth

Finally, what is really important with any production is making things happen. Inevitably, there are going to be last minute changes and requests coming from the top. We as are professionals, of course we do all in our power to make these things happen. For example, when the band requested a specific song for walk out music and that they also are able to hear it on stage, well the orders get rushed to front of house so we can make that happen.

Dave Rat

 

 

Comcast Center, formally Tweeter Center, formally Great Woods in Boston but actually is 25 miles away from Boston in Mansfield Mass.

The thin crust of an eggshell that had formed around my nearly two years at home has been sufficiently shattered for me to begin to see tour world clearly. You would think that well over two decades since my first tour, I would have a nice warm familiar groove to settle into. Hey, isn't touring like riding a bike? Once you do it, you know forever. Perhaps, but with so many complexities and patterns I have carved into over the years, which one will I be? As I re-enter tour life, which of my past tour patterns will envelop me and which pattern do I strive to embrace? Regardless of my intentions though, the unique dynamics of each band, travel rhythm, fellow crew friends and my life stability levels all whirl-spin together and at some point I find out where I land. It at that point which I can truly decide which direction to head.

And here I am starting with two extremes and working my way to the middle. Deep dives into technical ponderings in between reckless indulgence in the freedom from the mundane responsible of the everyday land locked life I lived just few weeks ago, all magnified by the gaping holes left where the things I miss reside.

Finishing up the design phase of adapting the sound system to sheds and finding a stable tour pattern. Must drink less because if I continue at this lushy pace I will start losing everything thing, like cameras, friends or my own humanly self. Oh, and also I need to work on finding this tour's hobby or adventure. Speaking of tour hobby, this is the exact venue that donated the seat to the electric go-cart I made on the 2003 Peppers tour!

http://www.ratsound.com/cblog/archives/177-Day-221-Dec-30-Home.html

And so, nothing truly is perfect but some things are way better than others and now that we have the sub Vortex system all dialed in, at least we are done doing arenas so I get to start all over. Would not want to get bored and running with 'typical' is soooo booooring.. Lets take a dive into the pleasure of coming up with a brand new shed design. Fortunately, the design of the various amphitheaters (sheds) varies so drastically, that nailing down a repeatable setup is going to be a challenge indeed. My strategy is to come up with three setups to select from and pick the optimum for each venue. The Vortex is choice #1 and surprisingly we were able to run with it in Milwaukee

How well do the Vortex actually work? On the down side, when you light up an entire arena with low end and really cover the sides well, the sound of the subs is naturally going to be a more 'roomy' over all sound. But that is a price I have to pay for getting a more consistent sub sound in the room.

Also, we are doing really well at getting a smooth sub level in front of the stage, but at the diagonals where the sub Vortex stacks are focused toward the deep part of the arena, there is substantial output, especially during the drum solo. So the sub output is hotter than I would like in those areas. That said, it is much more consist ant than any other ground stacked sub setups I have used. Oh, plus they look cool and I can alter the coverage a bit with delay times and levels.

One of the goals with the sub setup was to be able 'fill and not kill.' As in fill the arena and not kill Steve, Doug, Robert and Chris, the backline techs. Steve Walsh drives at the other end of the audio snake during the show and literally five feet away from the back of the subs. Chris is even closer. I will rock some pics of all the tour humans at some point but first I have to remember all the names.

Anyway, take a peak at the alternate shed setup

And the design notes:

And no matter how large you roll, someone somewhere just has to one up ya!

Dave Rat

**** Sound Nerd Speak ****

So it did not take long and all the attention paid to the Vortex setup has give rise to yet another naming possibility

I guess the next step is finding volunteers to test for proper function.

Welcome to my new office. Nice high ceilings, roomy, I even brought my chair from the Rat office so I could feel at home.

I realize the decorations leave something to be desired, but that will have to wait, nerd things first. Deciding what gear to bring on tour can be quite a challenge. Should I make the digital jump? Should I push for a $200,000 XL8 console? What is the newest latest and greatest? What are the budget, truck space and venue space constraints? Where o where shall that budget be spent and how do I justify the the expenses, at least to myself if no one else. My theory for getting the gear I want is simple and very effective. "Give me the tools I need to do my job and I will guarantee a quality result."

So what do I do when I could have just about anything I want? Well, first of all I get the what I truly believe to be the best large scale PA on earth right now. Next, I grab a nice big pile of old outdated clunky gear. Not the 'old' where they are getting expensive, but rather the 'old' where anyone can collect the stuff up by scanning eBay . I am running large! I am pretty sure that all of the gear I touch, there is only one piece newer than 15 years or so old.

Up top left is my Drawmer 1960 stereo tube comp I use on vocal subgroups, the meters don't read quite right so you never know if you are left right matched and it is perfect.

Next are 2 BSS DPR 404 quad comps that cover the rest of my subgroup compression. Stereo guitars, bass, Kick/Snare, stereo toms and metal things. I love those comps, I hate their elder brother, the DPR 402 though. Where the 404 is smooth and easy, the 402 are hard and useless to me.

The Aphex units are just for show and backups in case the 1960 dies

A couple Klark DN510's stereo gates and DN 514 do all my gating. Pair of kick mics, pair of snare mics, 2nd snare, 2 toms and spare. All good, I have tried many gates but keep coming back the 514's. I would just use 2 quads but the stereo units allow me to trigger both kick gates off of one kick mic. Same with snare top and bottom.

Next down is a CD burner that is fairly new but I do not count that as it is not in the signal path of the rock show.

Top right is the only real exception to the 'old and not getting expensive' theme. The PCM is my flat out favorite reverb. Rat owns 6 or so of them and it is pretty much all I use. In fact it literally on this tour is all I use. One reverb unit does vocals, toms and snare.

Being a guy that loves frill and uselessness in the audio mix, plus the desire to get all ego'd out on the sounds, I felt it necessary to actually use a second effect unit. I know, you are thinking two effects for an arena tour? Why so many? Some things I just cant explain, furthermore I am very embarrassed to say that the second effect is actually brand new. Yikes! But hey, this TC Helicon Voice Doubler works very nicely at adding a subtle but enjoyable thickness to the vocals.

Next in line is my trusty Eventide H3500. I brought it, thought I may need it but it is just filling rack space and acting as a spare.

Next is the broken DAT player that the door wont open on.

The next three units are dedicated to subwoofer processing. Since I personally refuse to scroll through any menus while I mix , even when I do use the 3500, I memorize the programs and punch them in directly. But for subs, I want some control. I want t low pass that allows me to shave off the top and just have the sub lows, so I use the BSS FDS 310 for that.

I also like to be able shave off the bottom to de-boomify the subs, so I use the high pass filters in the KT DN410. One side of the 410 allows me to EQ all the subs and the second side is just on the Rat Super Subs.

The Symetrix 501 compressor allows me tighten up the lows a bit. Since I use only subgroup compressors, the subwoofer sends from the kick, toms and bass are able to sneak out un compressed. The 501 solves that issue if I so desire.

I insert the EQ - x-over - comp chain on the subwoofer aux

In the lower rack is a pair of Meyer CP 10's. One is inserted on the entire PA left/right and I use to tune the room. The second is a KUDO modifier EQ that we use to fine tune the KUDO to sound as close to the K1 as possible.

The top BSS graphic is in series with the top CP10 and gives me a quick grab EQ that I use during the show. I have 250 and 2.5 K knobs pulled so I can Braille my way to the frequencies. Cause you know that I am a sound guy, not a lighting guy. Therefore I try to keep light to a minimum in my area and run in the darkness. The next BSS does a whole lot of nothing.

Moving over there is the archaic DBX RTA-1. I doubt there are many left surviving but I love it. It is truly the only RTA that actually looks like what I am hearing. All these new fangled laptop analyzer are quirky and jumpy. Plus, with a few flips to some setting, they can pretty much look any way you want them to. Which always leaves me with doubts and the fears of 'oh wait, the blah blah' is set wrong. This DBX thing is a no brainer, set gain, set decay to one of 4 choices and done. Simple pure easy confidence is what I seek, I want to glance and see a visual that has a strong correlation to what I am hearing, all that excess accuracy capabilities is useless to me during the show.

Next down is a pair of XTA 448's that I don't mess with but they control press feeds and Sub Vortex/Rat Super processing and sub delay times. We used the XTA for Vortex delays rather than the LA-8's because it was faster for testing. We may drop the XTA on Vortex after we settle into the shed's.

And then there is a Shure PSM 600 transmitter that allows me to go wireless with my headphones. I still primarily rely on the RTA, my ears and comparative reference points to tune the sound system. The wireless headphones allows me to tune the sound system to sound like the sound in the headphones while wandering around in the venue.

The Lab Gruppen power amp supplies juice to a pair of EAW MicroWedge 12's I run in passive mode as local listen wedges.

And finally, the clear com power supply.

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

And here is the full setup

 

You can never have enough bear spray at the sound board!

Dave Rat

Sitting at out first real show with full production after doing the listen wanders. All American Rejects were on stage and I had my first chance to get a solid idea of how the Sub Vortex system is working. Yes, Scott, Vortex is winning like 30 to zero so far. Whatever. Anyway, we are pretty happy with the setup. The diagonal fire focus is really effective but a bit too wide of an angle. Rear and stage side cancellation is substantial. I am going to do one change next show and run them the opposite directions as I am calculating much better aim and focusing deeper to the rear of the venue. The time alignment comes up much cleaner with B and C being identical in delay and D at about double.

Plus the cancellation s are better aimed to the side and rear and it eliminates the D to B cancellation aimed into the audience center. I realize that for you tech head types, my drawings are probably shockingly over simplified and lack all the fancy colors and such, but hey, this is how I figure the stuff out, so I am sharing the raw methods.

Here are the actual shortest distances from acoustic center to acoustic center. Though in reality some of the path lengths are altered by the cabinets being in the way.

Grabbing the two approximate primary distances of 3.6 feet and 6 feet and taking a look at the effect on cancellations we should see behing and stage side of the array

We can see excellent rejection in the 50 to 70 range for our B to A and C to A combos (50 is mid way between green and yellow but not shown). For our 6 foot DC and DA combos we see the polars below which offer more control to a lower frequency. The DB polars at 4 feet read somewhere in between these.

All in all we are seeing a good amount of cancellation and due to the various combos, it should be a well spread attenuation rather than concentrated in a narrow frequency range.

The Listening System

Moving on, check this out! We have four pairs of wireless transmitters/receivers with high quality omni lavaliere mics attached. These Sennheiser units are the same systems that video cameras use for wireless audio on transmission/reception and the receivers are the same units that are used for in ear systems. And while I am at it, and for some shameless self promotion, if you need any Sennheiser or any audio gear for that matter, give Daniella a shout at the Rat office and she will hook you up with great deal. Ha, tell her you are a friend of Dave Rat!

And Nick the Fly with the mics and transmitters.

We can place these at various locations in the venue. Though the mics are not perfectly flat in response, they are close. Since the data I am looking for is simple frequency response, we have the four mics and a hardwired RTA mic all run into console channels. We have calibrated by placing them next to each other and set gains so they all read the same sensitivity. So now I can PFL any of the mics and see the response of that mic on the RTA. I do not really care if the read out is flat, what matters is that the mics give me an RTA reading that looks like RTA reading from the reference mic at FOH mix position.

So now, very simply I can see on the RTA and hear in my headphones various locations during setup and sound check and we don't have to run a bunch of stupid mic cables all over the place. So far we have not built housings for the transmitter so that they can live in the audience during the show, but we are pondering a method.

These reference mics give us the power to quickly figure out if the sub Vortex system is working as desired, are totally wireless and easily transmit the distances we are dealing with.

Oh, and just for the heck of it, here is a link to the SB28 owners manual.

http://www.l-acoustics.com/manuels/SB28_UM_ML_1.0.pdf

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

Hmmm, did I mention that the drum riser flies? And spins, and tilts and Travis rocks the house in a huge way. Really cool to see and I get to push those subs right on up to vision blur mode! Check out this sexy setup!

And to further soften the landing from all the heady sound nerd world, this is my shorty Sammy

This here would be my other shorty, Maddie and the cookie we made. Why make a bunch of little ones when you can make one huge one. Go big!

And hey, there Taco!

Nick the fly, me and hey, my dad, say hello papa Rat!

My friend for over 35 years, say hey to Brian Rat who started the company with me. We did a bit of surfing at San Onofre before I left.

Don't mess with Taco! He is my guard blog.

Next up, lasers and perhaps a new name suggestion has been put forward for the Vortex. This one may be a hard one to beat!

Dave Rat

It is quite a drive from Vegas to Vancouver so I stayed an extra day in Vegas got a bit of work done and a bit of fun done before jumping onto the bus adventure. All good, 3 hour flight lands 30 minutes early, we taxi up to the gate, well, not quite the gate. We can see the gate but pilot informs us that there is a bit of a lightening storm. While the storm poses no threat to us plane people, the airport has decided that the humans that normally cruise around in those squished looking airport vehicles should stay indoors till the storm passes. I woke up two hours later pulling into the gate. A quick dash down to customs and oh my. They have unloaded the entire airport backed up constipation of humans all at once onto a meager smattering of customs agents working overtime. I felt quite at home as it looked like the floor of a small but packed arena with the only exception being that my backstage pass is useless here. Zig zag lines that would give Disneyland a run for its money on a weekend. So funny to keep passing the same people, back and forth we go till at last, with a few too many questions and a stamp in my passport I am on my way.

Ooooh. Yikes, look at that taxi line. Double yikes as the 1/2 block long clusterfucks is aimed straight at a 2 little Prius Taxi's and every few minutes another zips in. "Is that really the taxi line?" "Nope, that is the the taxi line" Pointing to another 1/2 block line twice as thick that wraps around the other side of the road. "This is the front half."

Five motionless minutes spent at the tail end convinced me to seek a better path. Free hotel shuttles looked hopeful only for me to discover that they drag you to Airport hotels and I'm headed downtown.

Aaargh and then I see it. A small sign. "Public Transportation." A bit of a hike, a bit of a wait and on I hop. "I am sorry sir" eyeing my $20 canadian bill, "We only take change on the bus." But before I had a chance to ponder my next move, he goes on to hand me a bus pass, wave me on board and gesture to the next person in line to get on."

Welcome to Canada and I smile as not fighting the things beyond my control brought me in for a smooth landing. A very very slow, but smooth landing.

I must remember to have one of the hotel housekeepers teach me how to make a bed. How do they do it? It would take me half the day to get a bed to look like this! There must be some secret tricks or something.

Ok, back to **** sound nerd speak **** lest I get distracted, not that that ever happens.

Subs. So after all the various configuration were sifted, I narrowed to three with a distinct focus on one design that seemed most promising.

First though a bit about distance and subs. There is a magic distance when spacing subs for maximum forward summation and maximum rear rejection of 1/4 wavelength of the frequency that you want the most rejection to occur. The reason is that if you space them one behind the other 1/4 wavelength in distance and then time delay the front 1/4 wavelength, then in front they add together with minimal loss while behind they are effectively distanced at 1/2 wavelength. Since 1/2 wavelength is 180 degree out of phase, you get maximum cancellation at that frequency.

Which frequency you design for depends on your subs and other factors but typically 40 to 60 hz is pretty good. 1/4 wavelength of 50 hz is about 5.5 feet and a good place to start. That means that a five foot spacing from center of sub to center of sub, with the subs being around 4 feet wide, is about a 9.5 foot width with not much gap between them. The good news is that it is close to the size I am seeking for this design to fit under an 8 x 8 deck.

So far I do all my designs on paper with computer assistance only for drawings, based primarily on logic and experience and I do the math by mostly by hand. But hey, I mix on an analog console as well. But that does not mean I can not use computers to check my work, so I sent it off to Sugden to run some projections and see if I am on base and have taken all the variables into account.

The Spiral or as Scott Sugden came up with, The Vortex are the names I am considering. Have you noticed yet that I like to name things? A bit of fun and makes it easy. How about a vote? Spiral or Vortex?

Anyway, here is how it is supposed to work. There are four stacks of three SB 28's with two stacks facing forward (toward mix) and two stacks facing to the side (off stage).

Sub "A" stack is the primary drive on each side with stack "B" time delayed to increase level forward and cancel level behind. Stack "C" is time delayed "A" as well to increase level to the side and cause cancellation on stage. Stack "D" is time delayed to increase level at 45 degrees while canceling at 235 degrees.

All in all the primary array focus is 45 degrees and by increasing or reducing the level of stack C and some altering of delay times, the coverage can be narrower or wider. The interaction between "D" and "B" also adds somewhat at 200 degrees and cancels at towards stage. The "D" to "C" interaction is forward beneficial as well as "D" has the longest delay time.

The end result I want is a well diffused power alley, significant power to the deep diagonal throws of the arena, controllable side coverage, excellent rejection on stage and minimal overpowering of the people in front of the stage.

I know from experience that having two point sources for subs will cause some issues and I will get cancellations just to the sides of where power alley usually is. But, this should setup should be much better behaved due to the effective focus 45 degrees off axis. The combined response looks a bit like a butterfly.

To deal with gaining more control over power alley and help diffuse the cancellations off to the left and right of center, we are carrying 4 stacks of two Rat Super subs evenly placed across the front of stage. The time delay on these will be focused on FOH and the level can be varied to optimize.

To make these things easy to setup, Nick the Fly designed some inserts that our tour set carpenter made for us:

Fitted inside the wood aligners allow us to easily repeat the setup. Another wonderful aspect about this sub setup is the creation of a special little hang out spot for the sound techs in case they want to just get away from it all for a bit of relaxation, as Manny is demonstrating.

Having these ideas and projects is all good and fun but actually making them work properly is and testing how well they work is another challenge. So now it all about brainstorms and unraveling the fact from fiction with Nick the Fly. Nick and I have toured quite a bit together in the past and has been extremely involved and familiar with the progress of these concepts into reality over the years. Did you know Nick actually was the cabinet builder for many Rat designed boxes. I would send actual napkin sketches and he would build stunning enclosures.

As I mentioned, I personally am not so much a pretty picture kind of guy that keeps messing with software to try and find a coverage that looks good. Rather, I try and solve from a logical approach, try to confirm with the software and then do actual testing. Then, if logic, testing and software all agree, I gain confidence.

So to address the measurement side I have finally put together something Nick the Fly and I have been discussing doing for years now. How cool would it be to have a simple system where we could drop reference mics in various locations around the venue to monitor the sound without running a mile of mic cord everyday. A system that does not rely on trusting whether you are getting a correct reading from some super high tech measurement software. But rather a quick look and listen in real time.

Well, I will describe that some other day.

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

So if that was not enough thinking for you, I have a bit more. Jim, Nick the Fly and I were out for a wander and happened upon my very first Canadian yard sale. Hey look, speakers! I love speakers and upon closer inspection I began to poder a question and have a little test for you.

Ok, so there are these speakers in your car and you think to yourself, "hmmm, I want to take these speakers out and put in new ones." Now for the big question. Which tool do you grab out of the tool box?

A) The screwdriver with a square drive and loosen the screws

B) The 3/8" socket wrench and loosen the nuts on the back and remove the nuts

C) The oxyacetylene cutting torch and shoot flames into the inside of your gas powered vehicle

If you guessed "C" you are absolutely correct! For the rest of you, come on, think first before you do things.

Dave Rat

More Homework

So just as I did for the Coachella sub setup, I set a few goals and restrictions to see where that would take me with the design. And just as I did with Coachella, I have the honor of being able to run the designs by Scott Sugden from L'Acoustics who has the skills, experience and software to sort through the options. I really do feel fortunate to be able to not only try and figure out cool solutions but also to have the support people and sharp humans that can help me implement these things on a fairly large scale.

Lets start off by clarifying a simple rule of thumb regarding configuring speakers.

The wider you stack speakers horizontally, the narrower the coverage is horizontally. The higher you stack speakers vertically, the narrower the coverage is vertically. This is counter intuitive at first as it is tempting to stack speakers wider and wider to cover a wide room. When using horns and with mid and higher frequencies that can be easily controlled in their directivity, stacking wider for wider coverage can work well. But the rule of thumb is based on multiple speakers reproducing the same signal with their coverage patterns overlapping.

With sub woofers, overlapping coverage patterns are all but unavoidable, so the rule of thumb works well, especially with larger arrays.

OK, so the premises I am following are:

1) Horizontal sub arrays reduce horizontal coverage and create a power alley in the room center reducing coverage to the sides. - I need to keep the sub arrays compact horizontally.

2) Vertical sub arrays tend to reduce vertical coverage. A flown vertical sub array further messes up vertical coverage due to the reflection effect. I will try to keep the subs on the ground.

3) A stacked vertical sub array is a bit more forgiving in its vertical coverage than a flown array. Yet more concerning is that the tall ground stack in an arena will usually block sight lines unless it is behind the band, and we surely do not want the band in front of the low end I am going to dumping on the audience. Keep the sub array compact vertically.

4) A stage center horizontally ground stacked sub array blasts the front row of humans and tends to arch over backwards onto the band. Even with a cardioid sub array placed stage center, my experience is that, having the singer just a few feet from the primary subs generating enough lows for an arena creates an inevitable mess. Avoid putting lots of subs stage center.

5) The setup must be easy, repeatable and be able to cover the venues without the time consuming tedium of meddling with multiple interacting delay times every day. I want two or three clean presets that I select from. Maybe a 180 degree coverage, a 220 degree and a 270 degree. Create a sub setup that allows changing coverage without re stacking.

6) Finally, as with any useful idea, the less negative side effects, the better. So the sub array ideally should not reduce venue capacity, block sight lines, push out the barricade, look ugly, or cause any issues for backline, lights, video or any other department. Plus it would be really cool if it was easy and fast to setup.

Hmmm, that really tilts toward putting subs on the floor and off to the sides as the best of the options without diving into an some esoteric 3 dimensional flown sub arrangement that would change the rules a bit. In order to reduce the power alley effect, creating a sub woofer setup where each side has a bit of reduced coverage in the room center should help.

Anyway, based on those parameters and keeping in mind the quality of the overall show as whole, the most finessefull solution seemed to be to refine the sub cannon design for added control and improved coverage. Reducing the quantity of forward facing subs towards the stage middle would be good as well.

Here is the Peppers sub configuration drawing for the 2006 -2007 tour

And a picture of it

I will also need to account for the fact that I will be using the L'Acoustics SB28's rather than the Rat subs I had on Peppers tour. I love the Rat subs and with the new Rat Super Sub, the added power is awesome. But Rat Sound has the privilege of being one of only two vendors with a K1 system in North America during this pilot phase of the K1 system release so both Rat and L'Acoustics really are focused on keeping it all intact as a complete system so we can really learn the rig and share what we experience with the manufacturer. That is not to say that it can not be augmented, but for the primary system it is all about a matched L'Acoustics rig.

So I am going to walk the line between off the shelf L'Acoustics with a bit of optimization based on my past experience and setups.

Picture time. This is pretty much the way I start projects. First establish a rough goal based on fulfilling the need or solving a flaw to what is existing. Next start drawing pictures and try and cover all possible permutations regardless of whether they are feasible or not. I then sort through the pictures and weed out the weak ones, hopefully settling in on a small range while weighing the assets and issues. Finally refine, redraw, build and test the winners out.

Just to give you an idea of some of a few of the 20 or so layouts I went through, here are some really rough stage right sketch's that did not make the cut for this tour.

The Fan. This would have the rear three at zero time and a delay added to the front three. I never ran projections as it was too big for what I am working on here.

 

The Focus. With all the work on the design of the EAW MicroSub, I have been diving into and using mechanical coupling arrangements, this is a triple sub setup seemed interesting. The delayed center can be timed to steer the coverage a bit. Never tested it and it seemed to be too limited in control.

Two behind three. This is a 12 x 12 foot and cumbersome. But perhaps you can see where I am headed with attempting to have control over the forward fire, diagonal fire and side fire while offering some cancellation on the stage and behind the subs where the monitor position and techs will be.

The Quad. The size is getting better and with subs pointing forward and to the right combined with delays it could offer some control. I really want power delivered about 45 degrees to the right of center. That tends to be the longest shot in an arena as well as a place where people will not be really be too close to the subs due to sight lines.

The Circle. Similar, and though you often hear that subs are omni directional, it does not take a rocket scientist to walk around the back of a subwoofer and hear that they are a bit louder and more direct sounding in front. This sub circle could have all subs facing inward or in several differing directions.

 

The Split. The next one actually is pretty good and fits in an 8 by 8 foot area. I could time delay it it for a 0 degree, 45 degree or 90 degree focal point. A bit light though, I was hoping to get 12 SB28's per side and to match the stage height so I am looking at 3 per stack. Meaning this is a 9 sub array. The sub on the right would add power to the side while offering some cancellation on stage. The sub up top in the drawing adds power forward and cancellation behind. the interaction between the top and right subs should cause some cancellations to the upper left power alley area and lower right 135 degree off axis area. By messing with levels a bit, the coverage could be altered a bit. Plus the distances are hovering around that magic 1/4 wavelength of 60 hz range which is useful for cardioid sub configurations.

Oh, and let me not forget the most important part. The Carpet.

How can we possibly do a rock show without a nice fuzzy carpet to stand on!

Next up, more subwoofery stuff, some simple cool measurement tools and running it old school style.

Dave Rat

Here we go Blink 182 and cool rock show. I have not really figured out my direction yet as far as blogging and adventures but in the mean time, I may as well rock on the tech side of things. Will work on losing my mind later.

The Los Angeles Forum was the playground for testing and getting things dialed in.

So what is new for this tour? Well, the new K1 rig is a monster! Truly some breathtaking horsepower, V-Dosc with nitro boost. Aside from the significant jump in clarity, it can pump enough low end from the main hangs to make the subs almost optional.

Similar to the Peppers rig, I am once again using an 8 foot by 8 foot sub array with a blow through aluminum grate on top that doubles as stage wings. It is a really cool way to go as it gives me a lot of freedom with the sub design without eating up valuable floor space while keeping the setup clean visually. My goal once again is to attack the issue of whimpy low end off to the sides of stage and while gaining control over how much power alley there is.

For those non-soundy humans, power alley is the term used to describe the area down the center of the venue where the low end tends to be more powerful than elsewhere. So in itself I guess a 'power alley' is good for the humans hanging out there but that also means that everywhere else is not a power alley. For some odd reason, it has become a commonly accepted practice to have a strong power alley. Personally, though I love the low end power, I really work hard to get the sound as consistent as possible throughout the venue. Forget power alley, I want a Power Valley and I want everyone in it!

Easier said than done. Turns out that if you stack horizontal sub arrays on the left and right sides of the stage, they will be loudest midway between them while off to either side of center the low end drops off quickly. One solution is to put all the subs in the middle which works fairly well and also tends to completely wipe out the band on stage with low end. Also, the center sub thing tends to really smear the heads off the humans parked in the front rows.

Another method that is becoming more common is to fly vertical line arrays of subs. This solves the blasting the front row humans issue quite well, offers improved low end off to the sides and a more reasonable power alley. The issues are that the vertical sub line arrays create these cancellation nodes that project like spokes just to the left and right of audience center. The cancellation nodes can be quite pronounced to the point where there are areas with almost no sub right next to areas with powerful sub sound. Another drawback with flown subs is that they create a sideways power alley. By that I mean that there is a power alley effect that offers strong low end at floor level that tapers off as you increase in altitude. You see, the floor acts like a mirror to subwoofers. When you stack subs on the ground, the subs are sitting on the mirror, in effect doubling the energy radiated.

Just as power alley occurs in the horizontal plane (wide vertical, narrow horizontal) with subs stacked side by side on either side of the stage, a vertical power alley is created when subs are flown in a vertical line (narrow vertically, wider horizontal) caused by the interaction between the flown sub array its reflection in the mirror (floor). Since power alley is in effect most pronounced for the locations horizontally equidistant from the subs, with a flown sub line array, the subs are loudest for humans vertically equidistant from the subs and their reflection. In other words, there are challenges in the vertical coverage with the center of power alley at your feet dropping with elevation. For a flat field show this is not really an issue, and can be an asset but in arenas and venues with humans up high, the reduced vertical coverage can be a significant issue.

Several years back I was doing a show where the sound vendor swore up and down that we needed to fly subs. Even after I killed the idea, I was surprised to not only find that they were flying subs when I arrived, but they went on to tell me they were going to fly twice as many. Why? Well, they went on to explain that they were having trouble getting low end into the balcony area of this huge indoor sports venue. After a bit muscle flexing and much to their dismay, I pressed the issue, made them drop all the subs and we ground stacked. I then personally walked the balcony with the head sound tech during the support act. "Better?" I asked. He was quite surprised and fully agreed that the subs to the upper sections issue was solved. The price? Well, I had power alley back in the horizontal again which meant the lows dropped to the sides. But for that venue which was not very wide, the percentage of people that heard solid low end was significantly increased.

Alright, time to fly, more to come tomorrow as I try and regain some bloggery momentum.

 

Dave Rat