Monday, February 27, 2012

Easy....and crazy enough it just might work

I took a little time in the middle of microphone element repairs to do a Proof-of-Concept for the Easy Button.

Took apart the Staples Easy Button, de-soldered all the components and cut the traces on the PC board, leaving just the button. Ran a pair of wires out and hot-glued them in place so they wouldn't interfere. The button as built makes a lovely stapler "ka-chunk!" noise when pressed, but that was, sadly, inappropriate for use in an FOH station exposed to the audience. However, a little careful re-shaping of the metal spring took the "click" out without changing the firm feel of the button.

I connected it to my all-purpose Arduino-based wire-to-MIDI interface, and plugged that into QLab. The Stage Manager admired it so much she's going to try using it as a GO button for next weekend's performances.

Perhaps by then I will have gotten into my USB-AVR breakout board from Adafruit (or the old and sadly no longer made or supported Bumble-B) and made a more self-contained solution. Or perhaps not! This show is all about exposed technical bits. It's an Atom-Punk setting, after all. I've got a bucket of water with EL wire wrapped around it and a microphone sticking inside...I slosh the water around for a live sound effect in a couple of moments of the show.

(This is very much an insane cludge of a sound design. The effects are on laptop playing both through the headphone jack and through an Ozone USB keyboard for an additional two outputs. OS 10.5 was being stupid about combining these as an Aggregate Device but that turned out to be for the best anyhow. The drums are being submixed via a Presonus FP-10 into Cubase -- for EQ and compression. So I've got a maze of wires running all over the place.)

I've blogged before about the problems I've had in that space, and others, about the conflict between a flat coverage by house speakers, and an equal-loudness mix between vocals and orchestra. The fight is always against monitor leakage (especially when the pit is using amplified instruments like keyboards, basses, and guitars); since monitor leakage models as a large point source it falls off by roughly inverse-square. Since the vocal reinforcement includes delay speakers to cover the rear of the house, the fall off is whatever we set it for. This means that getting decent levels at the rear of the house is essentially at cross-purposes with having the same mix between vocals and band in all parts of the house.

Worse yet, the vocals are coming from distinct point sources high in the air (the center cluster in many shows) and the band source is a large, diffuse source below the level of the stage. This means the singers and the band don't sound like they are in the same universe.

This can actually be a help when you are trying to help the listener/audience discriminate between competing sounds. But the spacialization you really want is that the vocals appear to be coming from the actors....not from some speakers far overhead.

For several shows we've struggled with the problem of poor front fill. With the orchestra pit "in" (aka the elevator lowered and a moat between audience and actors) the front rows are just barely within the field of the main speakers. By ghosting up a center cluster or some high overhead speakers pointing nearly straight down, you can help those first few rows while not completely changing what the rest of the audience hears.

With the pit covered the problem gets worse. And when they chose to add a false proscenium (cutting off all your speaker locations) the problem becomes critical.

After a somewhat rough opening night and several complaints, I came in (exhausted and with less than thirty minutes to work) with a crazy idea. Front fill at stage level will solve this coverage problem of the first rows of seating, but many set designers will not permit the visual look of those speakers intruding upon the lower few inches of sight-lines. Stage fill from the front -- to allow the actors to hear the band -- can usually be snuck in at barely above stage level. I had these, in fact. Which were part of my monitor leakage problem already.

So what I did -- with no time to work -- is turn the front fill monitors around and re-assign them to the reinforcement bus. Since they couldn't of course be on the stage, they went to either side and were angled sharply in (focus point about a third of the way back in the house). And since for various reasons my subwoofers were already sitting on the far corners of the apron, I was able to stick them on top and lift up the speakers by that much.

Then I pulled both the mains and the center cluster from the house mix, leaving it ONLY the newly re-purposed front fills and the delay speakers further back. As the last step, I moved in the side fill monitors and re-angled them to make them the sole stage monitor coverage (the band is really, really loud anyhow).

And it worked. I was shocked at how good that sounded. But then, these were the original top fills and were a pair of lovely, lovely Meyer UPM-1P's. So they are entirely up to the task of being front audience fills.

I suppose if I was really concerned I'd re-focus the center cluster to boost a little through the middle of the audience (right down the center aisle is basically worst coverage from all the systems). I am also slightly concerned about audience in the seats closest to the UPM's, but there is sufficient direct audio pressure from the cast I think that will compensate. I have the UPM's at 8 milliseconds of delay, a compromise between the length of their throw to center and the average 12 millis the entire system is set to (the delay bias here is to allow the actors to be perceived as primary sources via the Haas Effect).

The rear house speakers are still on their Meyer-set delay via the Galileo processor. I did a quick-and-dirty impulse check using a side-stick sample via Garritan Personal Orchestra, and I didn't notice the sound doubling as I walked the speakers from the center to under the rear speakers. And I'm running the rear hot; as close as I've ever been to a flat field across the whole house.

No comments:

Post a Comment