Riddle me this, Batman: When is an audio console not really an audio console? When it's a control surface. With digital technology running rampant, there are plenty of control surfaces out there masquerading around as audio consoles. We've got to recognize the differences or we're sunk.
If you're reading FOH, you already know that an audio console is a device with faders, button and meters designed to route and process audio. We've all plugged our mics into these desks and used them to mix shows. Ah, but a control surface would like you to think it processes and routes audio when really, it is nothing more than a very expensive mouse! Alas, this Mighty Mouse under your fingertips controls a computer, typically (but not always) processing audio in the digital domain. Now that we've identified the difference, why should you care?
There are a couple of reasons. First, let's assume that you are a touring engineer who doesn't have the luxury of carrying a P.A. system, and so must deal with P.A. du jour. Soon, you'll be doing a show where your fingers are running a mouse and not an audio desk. It's inevitable. With a little luck, the manufacturer of said device will have done a bit of homework to make the control surface look and feel like an audio desk with faders, knobs, some pretty lights and maybe an LCD screen to supply you with information. Truth is that the audio circuitry is likely to be in a rack somewhere either next to you or at the stage. Don't look for the insert points on the back panel of the control surface because there are none, nor will you find microphone inputs–all I/O is in the rack. What you will find on the rear panel of a control surface will be an Ethernet, fiber-optic or perhaps a FireWire port that links this mouse to the computer living inside the audio rack and routing your signals. You may also find a card slot that lets you load in the preset scenes you worked up at home prior to the tour. Hmmmmm.
You'll need to get accustomed to this pretty quick so you can figure out where to patch your favorite effects processor or vocal channel that you've been carrying around for the star of the show.
As you look around this Mighty Mouse, you will notice some unfamiliar things. There's a serious lack of pushbuttons, often limited to Mute (or "On/Off"), Solo and "Sel" (which will soon be your best friend). Alas, there will likely be only one set of EQ, pan and aux send controls that serve every channel, one at a time via the "Sel" button. When you press "Sel" on a channel, that channel is selected for control by these EQ, pan and aux knobs (and maybe a set of bus assign buttons), enabling you to access those controls without paging through a menu.
Audio assignment will be on a separate menu page designated for that purpose, but mute and fader grouping will be elsewhere. You'll still have channel and master faders, but there's a good chance that you won't find any audio groups or VCA group faders. That's because none of the faders on a control surface are audio faders anyway –they are either VCA or DCA (Digitally Controlled Amplifier) faders so any (or all) of them can be a group master. Remember: Since audio is handled by the I/O rack and controlled via CPU, the CPU will deal with assignments.
In addition to the operational difference between an audio desk and a control surface, there will be some distinct advantages. Almost certainly, there will be a compressor and a gate on every channel, so you won't have to physically patch them in (though you'll have to access a menu page). You may be able to use 'plug-in' software that simulates your favorite comps, gates and reverb, but you won't need to worry about getting yelled at by management for carrying another rack. You'll probably have the ability to link or at least copy EQ settings so you can create EQ for the overheads and copy it to the high hat and ride cymbal channels. Ditto for the vocal compressors.
System installers will find that they no longer need to run quite so much (if any) copper between the stage and Front of House. This is because the stage rack contains A/D circuitry to get the mics into the digital domain, where they can be routed to monitor and Front of House mouse (!) via optical cable if necessary. Since the conversion happens near the mics (onstage), the length of copper wire through which audio travels is kept at a minimum–reducing RFI and maintaining sonic integrity. A byproduct of this is that there's almost no chance for a ground loop between FOH and monitors because they are not connected via copper. In venues that might require the capability, it is usually possible to hang another mouse on the system, adding an additional mix position to the monitor or FOH rig in any location of the venue. Imagine a scenario where one monitor engineer is responsible for the star performer's monitor mix and a second is responsible for the band monitor mixes. Simply add another mouse (mixing surface) and they can stay out of each other's way while using the same audio I/O rack. Try that with an analog desk.
Oh, one other thing: If some jerk spills a beer on the desk, it may cause problems, but it won't shut down the show.
In addition to being the Front of House engineer and tour manager for Blue Öyster Cult, Steve "Woody" La Cerra teaches aspiring audio minds at Mercy College in White Plains, N.Y. He can be reached via email at Woody@ fohonline.com.
