Let's Go Shopping! (Part II)

In Uncategorizedby tfwm

With a thousand and one choices for consoles out there these days, the question turns to defining your needs for the console so you can narrow your search. What do you really need, versus what will do the job? What bells and whistles are actually worth having?

Let’s continue our checklist (first part of the article ran last issue) of features commonly available on consoles today. Then you can use this list to go shopping for the right console to use in your house of worship.

Master Section
It’s easy to add up the number of inputs that you need for a console, but remember that having lots of outputs is nearly as important. There are lots of ways to use multiple outputs. Here’s a small sampling of typical applications.

Subgroups– Let’s say you’re happily mixing along during a worship set, and the time comes for the announcements. You remember hearing me say during a church sound workshop that you should leave the minimum number of mics open at any given time. So you grab all of your channel faders and pull them back to minus infinity and push up the pulpit mic for the announcements. Only to realize that right after the announcements, the same worship team is going to come back to do the offertory music and you’ve just destroyed the mix that it took you the last thirty minutes to create. The subgroups can become your saving grace. Simply group similar channels together in a way that’s logical to you–like grouping all of the backing vocals together on submaster one, keyboards to submaster two, guitars on three, drums on four, choir on five. Then when the time comes to pull down all those channels during the announcements, all you need to remember is the position of those 5 submaster faders instead of all 47 channel faders. Even on a console that has eight submasters, I’ll often use only three or four submasters. God only gave me ten fingers, and I usually mix with the submasters under my right hand, and the worship leader’s fader under my left index finger. Submasters make mixing far less stressful, and much more effective.

Matrix– The first matrix output I ever saw was on a Yamaha PM1000 in 1981. I didn’t know what it was at first, but after figuring it out I discovered that it could be a very useful feature on a live sound console. For example, if a mono house mix is fine for recording your services, you could easily feed your cassette deck, MiniDisc, DAT machine or CD burner directly from a matrix output. The matrix could also provide you with an individual level control for the feeds to a hearing assistance system, the distributed speaker system in the foyer and hallways, a feed to the cry room, the nursery, the kitchen, the parking lot, or even the pastor’s offices. You could even use it as the feed to separate delay zones in the auditorium, allowing you for example to turn off the upper balcony system if there’s no one sitting up there. The matrix gives you a feed from each of the subgroup outputs, and allows you to mix those same elements in each of the matrix outputs. For example, let’s say that the console has four subgroups, and offers a 4×4 matrix. What that means is that you can deliver a separate mix of those four subgroups to four different locations. By the way, I have seen some churches use the matrix output as their main house output and, while sound will come out, that’s an awkward way to feed the house loudspeaker system.

Talkback– The talkback feature provides an easy way for the sound mixer to communicate with the worship team on stage, or even to make an announcement over the house system. What’s cool is that if your worship team is using headphones instead of floor monitors, the sound mixer can communicate to them even during the worship set without the congregation ever hearing it. I’ve found that to be highly valuable on several occasions. If you’re careful with the levels, you can even discretely tell your pastor over the front stage monitors that he’s forgotten to switch on his wireless mic. If the console doesn’t have the talkback feature, it’s possible to recreate all of its features with a spare input channel, but that means giving up a channel.

Effects Return– The effects return offers a convenient way to blend the level of the effects devices back into the mix. It provides a line level input circuit that can be routed to the house mix, so in a pinch you could even use it to connect the CD player to play just the walk-in/walk-out music. I often bring the outputs of my effects devices back on channel faders, simply because for me it’s a little easier and faster to grab a fader than a knob. But there are plenty of reasons to bring those outputs back into the effects returns, especially when you run out of input channels.

Pan Pots– On a stereo console, the pan pots allow you to position each individual sound source somewhere in that left-to-right panoramic spread. If you’re thinking about installing a Left/Center/Right loudspeaker system, you should be looking at a true LCR console. On an LCR console, panning the pan pot full left feeds the signal only to the left cluster. As you pan it from far left to center, the sound will move only from left to center. In the center position, the sound is fed only to the center output (the center cluster). As the pan pot is moved toward the right channel, the signal pans from center to right, until at full right the signal is fed only to the right cluster. Some consoles provide an alternative approach to this panning system. They allow you to assign each channel or subgroup to the mono output, which would be fed to the center cluster. And they allow you to assign each channel and subgroup to the stereo output, which would be fed to the left and right clusters.

General Features
Oscillator / Pink Noise Generator– Having a sine wave oscillator and a pink noise generator built into the live sound console can provide a convenient troubleshooting tool. It’s even more valuable as a troubleshooting tool if the manufacturer provides a separate output on the back of the console for that oscillator/noise generator feed. That way it can be patched to any individual channel.

VI Meters / LED Meters– What most people call a VU meter is properly called a volume indicator, or VI meter. They are scaled in volume units, which is where the confusion arose. I’ve mixed for years with both types of meters, and can see advantages to both. Something valuable to look for on a console is to have a 3 to 5 segment LED meter on each input channel. They’re usually located near each channel fader, and let you keep an eye on the gain structure of each channel. Those input meters combined with standard needle-type VI meters for the main outputs makes for a very useful metering package for a live sound console.

VCA’s– Using a VCA-equipped console is an absolutely wonderful mixing experience. VCA stands for voltage-controlled amplifier. In most consoles, the audio signal passes through the fader, which is actually a variable resistor. It’s kind of like a rotary volume control laid out flat. In a VCA console, the audio signal doesn’t pass through the fader at all. Instead, the audio signal goes through the VCA, a small integrated circuit on each channel. The fader indirectly controls how loud the audio signal is by controlling how much DC voltage is applied to the VCA. All of that, however, is transparent to the user. The advantage comes in operating the console.

For example, on a standard console, you might follow my advice to pull all 47 of your backing vocal and choir mics down during the announcements to improve your gain-before-feedback while the pulpit mic is being used. As we discussed earlier, instead of pulling down all of those faders, you can get them out of the house mix by simply pulling down the submasters that they’re assigned to. But… on a non-VCA console, that only takes them out of the house. They’re still being fed to the stage monitors, and more importantly to any postfade sends like the reverb units. So even though you have no direct sound from a vocal mic, if a singer coughs while holding that mic nearby, your audience is going to hear a nicely reverberated cough. With a VCA console, the submasters also have no audio signal passing through them. The submasters simply adjust the DC voltage being applied to those channel VCA’s, which will corporately control their relative levels. So if you bring down the VCA submasters, they also turn down every individual channel assigned to those submasters! Way cool! And if you mute the VCA submasters, that also mutes all of the individual channels assigned to those submasters. VCA consoles were first introduced to the recording studio market because they allowed the mix to be linked to automation. Fader moves were recorded digitally as the multitrack tape rolled, and could be replayed at any time. The same automation feature could be very powerful if used live, however most churches don’t link their music to time code or MIDI time code, which makes that feature less important.

Programmable Mutes– Programmable mutes allow you to mute certain groups of channels irrespective of which submaster they happen to be assigned to, or even if they’re not assigned to any subgroup. They were originally found on VCA consoles. By incorporating MIDI capability in some consoles, manufacturers have been able to provide programmable mutes without having to use VCA’s, which has introduced programmable mutes to more reasonably priced consoles.

As you can see, there are lots of things to decide on as you shop for your new live sound console. Make note of the features you’ve read about here, and use them to build your shopping list. Then go have fun shopping!

This article was first published in the March/April 2001 issue of Live Sound International. www.livesoundint.com Used with permission.