Thinking Outside of the Box

Computer-based recording is great, but putting some outboard gear into the mix (literally!) has the potential to make it even better. As one example, external summing buses are getting a lot of attention because some people prefer the sound imparted by going through analog gear instead of a DAW’s built-in mixer. But why not go all the way, and send your DAW channels through a full-fledged analog or digital mixer?

Here are some of the benefits:

• There’s an inherent control surface. We’re talking physical faders, panpots, send controls, and the like, all of which are definitely more fun than using a mouse.
• Free dithering. Sure, it’s not as sophisticated as the dithering you find in a DAW or digital audio editor. But whenever an analog device is involved, some hiss will creep in — thus smoothing out a digital signal’s quantization noise at the very lowest levels.
• No problems using external gear. Although more programs are making it easier to use external processors, you can just stick a processor in the mixer’s send bus and be done with it — no “pinging” for latency, and no using up audio interface I/O.
• Lower CPU load. Placing an EQ in every channel of a DAW’s virtual mixer plus a convolution reverb in an aux bus definitely asks the processor to do some work, but using the EQ and other processors in an external mixer doesn’t. (While the mixer EQ might not be as good as a top-drawer EQ plug-in, it may very well be better than the “stock” EQs included in a DAW).
• Good for recording, too. When it’s time to record, you have plenty of inputs and faders for setting levels.

GETTING THERE FROM HERE

With an analog mixer, you’ll need an audio interface with lots of outputs in order to patch each audio interface output to each mixer channel input. In fact, unless you’re using a limited number of tracks, you may not be able to have a physical mixer channel for every virtual channel you want to mix in your DAW.

The solution is to mix “stems,” which you can think of as groups. For example, you could premix the drums within the DAW to a stereo aux bus, requiring only two channels from your external mixer. With keyboards, you may not even need audio interface outputs, as you can drive the keyboard via MIDI and then send the keyboard outs directly into the mixer (it’s even better if the keyboard has multiple assignable outs).

A digital mixer gives you other options. For example, if it has an ADAT optical input (“light pipe”), and your audio interface has an ADAT optical output, you can send eight channels at 44.1 or 48kHz from your DAW to your mixer. Furthermore, if both support the ADAT SMUX protocol for multiplexing signals over dual ADAT interfaces, it’s possible to do 88.2 and 96kHz as well. In my own setup, I often use the two ADAT outs from the SonicCore (formerly Creamware) SCOPE card to feed two ADAT ins for my Panasonic DA7 mixer (Figure 1). This gives 16 channels of hands-on mixing, without needing 16 cables snaking from one to the other — two fiber-optic cables carry all the ADAT outs. A less common, but powerful, protocol for shuttling around multiple tracks of data is called MADI and carries 56 channels of audio.

In any case, if you’re running a digital system, set the clock/sync settings correctly. Typically, you’d set your audio interface to internal clock, then sync the mixer digitally to the clock being received over the ADAT interface. Another option (if available) is using word clock to sync the mixer to the DAW (or vice-versa), or sync both to a master clock source.

HAVE YOU BEEN SAVED?

The biggest issue with incorporating elements “outside the box” involves saving a project. When everything’s done in the computer, saving a project also saves mixer and instrument settings. With an external mixer, it’s best to have some form of recall.

A digital mixer is best in this respect, as you can generally save a “snapshot” of the mixer settings and probably even save this as a MIDI sys-ex dump, which you can store in your DAW. Upon opening the DAW’s project, it’s easy to send the sys-ex to the mixer to re-create the desired project settings. If the mixer has moving faders, you may similarly be able to save those moves.

An analog mixer is more problematic, unless you have a high-end model with automation. In this case, you’ll need to use the tried-and-true methods: notes with pen and paper, or photos of knob settings.

Regardless, try mixing outside of the box at some point . . . you just may find you like the process.

JARGON JOCKEY

ADAT Optical Interface: When the Alesis ADAT recorder was introduced, although it had standard analog ins and outs, the company figured that people wouldn’t want a rat’s nest of cables, especially if they were going to use three ADATs to do 24-track recording. So, they devised a simple, elegant audio interface based on using standard, inexpensive fiber-optic cable to carry eight channels of digital audio. Although the ADAT has more or less faded into history, the interface lives on with mixers, audio interfaces, and other devices.