The Surround Dilemma

Is Your Studio Ready For Multi-Channel?

Surround sound was hailed as something of a burgeoning savior for the audio industry — manufacturers hoped that everyone would want to be completely enveloped in sound, whether in their home theater, in their car, or in their bedroom. And the format has taken off well, at least as far as movies and video are concerned. Prices have dropped on inexpensive “packaged” surround sound systems, and consumer adoption of surround seems to be steadily growing.

For pure audio, though, the story isn’t quite as upbeat. There has been growth in the world of surround music, and with the ongoing support of DVD-audio and SACD, this should continue. However, many consumers that I speak to aren’t aware that you can even get surround format music-only releases. (As an interesting side note, virtually every person I play surround music for immediately falls in love with the experience and wants to get it for themselves.)

So the problem at this point, for many studios, is of the old “chicken and the egg” variety. Clients aren’t asking for surround audio production, and consumers are still slow to pick up on the availability of surround (outside of movie releases). Which leaves most of us with a dilemma in looking toward the future: What should you do with your studio? Should you make the jump to surround? Some studios have, especially those facilities that do a lot of audio-for-video productions. Many newly constructed studios are making sure that they’ll be ready for the surround revolution by pre-wiring for surround speakers, etc., even if they’re monitoring in stereo for the time being.

Many existing studios are taking a “wait and see” approach. When they feel the time is right, they’ll make the jump and implement surround. This is certainly the “safe” route to take, although the potential is there to miss surround work that’s being done now, as well as the opportunity to learn the techniques and technology required now, while the format is still in its nascent form and there are no real “guidelines” for how a production should be done.

The decision will depend on the kind of work your studio is doing now, and where you see it going in the future. If you’re primarily doing radio spots for local businesses, surround is probably a ways off. Likewise if your main business is cutting demos for local songwriters and bands. If you’re mainly tracking and mixing for CD releases, it would pay to keep your eye on the surround movement, as music-only DVD and SACD releases are getting out there — many of the larger retailers now have high-resolution music sections where SACD and DVD-audio releases are featured. If you’re working in film or video, surround is a no-brainer: Most video features surround to one extent or another. Game audio is also moving strongly toward surround.

So the decision is yours, based on where your studio is currently at, and where it will be going. Fortunately, making the move from stereo to surround isn’t very difficult. Most audio production software supports surround mixing and editing these days, and there are even surround plug-ins available for processing. The biggest concern for most of us in making the switch is monitoring. The obvious thing is that you’ll need multiple speakers to hear all the surround channels. For 5.1, which is currently the most common surround format, that means you’ll need five “satellite” speakers to play the front left, right, and center channels, as well as the left and right rear channels. In addition, you’ll need a subwoofer to carry the “.1” channel (known as “LFE” or Low Frequency Effects) as well as to support extended low-end response from the satellite speakers.

Ideally, you’ll want all five of your satellite speakers to be identical, but if you’re just thinking about getting into surround, and want to experiment, you can at least get an idea of what’s happening with whatever speakers you have around. Likewise with the subwoofer; you can start with any subwoofer, but ideally you’ll want one that matches with your five satellites or that can be tuned to work with them. Most subwoofers will work with most satellites, but I have found that results vary. Some subwoofers just don’t work as well with certain satellites, resulting in audible “holes” in the frequency response of the overall system. The only way to know for sure is to try the speakers in your room.

Speakers are one thing; most of us can come up with enough speakers to at least try some surround experiments, even if they aren’t all perfectly matched. Controlling those speakers is another thing entirely. Very few (if any) inexpensive analog mixers are equipped for controlling the monitor level of surround speakers — yes, you can feed five satellites and a sub from multiple subgroups or aux sends, but surround panning of the input channels becomes a major mindbender, and you don’t have the instant “reach up and grab the volume knob” control you do with stereo monitor outs.

Many digital mixers do support surround output, some in a more user-friendly fashion than others. Usually there’s some provision for surround panning, and if nothing else, you can group faders in various ways to make level control more manageable.

If you’re ready to drop a few dollars, there are dedicated surround monitor controllers available. These usually correspond, more or less, to the monitor output section of a mixer, although they’re optimized for multi-channel level control. There are also more straight-ahead DAW level controls available for fairly reasonable prices.

You can, of course, do everything in your computer. As mentioned above, most audio production software such as DAWs supports surround very nicely, with graphic surround panning and routing. If you have a multi-output audio interface, you’re good to go. Set up the DAW to feed the 5.1 output channels to six of your interfaces outputs, then plug those outputs straight into your five satellites and subwoofer. There’s just one downside to this: You don’t have a hardware monitor level control that you can reach up and grab. Yes, you can turn down the outputs in your software using the mouse, but a better solution is a control surface, where one of the hardware faders is assigned to control the level of the six software output channels, or six output channels are assigned to six faders that are then grouped to move whenever one of the faders is tweaked.

You’ll also need to consider surround processing. Except for mastering applications, you can often get by with 2-channel (stereo) processors. If you’re creating a mix from mono and stereo tracks, you don’t need to compress, EQ, and otherwise process those tracks with multi-channel processors. For the six master outputs or for tracks that have been truly recorded in surround using multiple mics, however, you’ll get better results using processors (whether hardware or software plug-ins) that are truly surround-capable, especially for dynamics control — as with stereo, you don’t want the audio image to shift when the compressor or limiter kicks in on one or two channels of a multi-channel mix or track.

For reverb, you’ll get the realistic results using a true multi-channel processor. But I’ve had great luck using a pair of identical stereo units, one creating the ’verb for the front left-right speakers, the other dedicated to reverb for the rear left-right pair. (You can get by without a reverb feed back to the center channel as long as tracks panned to that channel have a feed into the reverb inputs.) Set the two units to the exact same program, then tweak the rear reverb unit with slightly longer pre-delay, early reflection, and reverb length until you get a nice, enveloping ambience.

For mixdown, you can utilize any multitrack recorder, such as a stand-alone analog or digital unit, or, you can mix back to tracks in your DAW. What will work best for you will depend on what you’re going to do with your mixes. Will they be played from tape? Will they be mastered at a commercial facility, then placed on DVD? Will they be surround-encoded for other applications? In most cases, you can deliver audio files (in generic AIFF or WAV format), one for each output channel (carefully labeled, of course!), delivered on CD-R.

I’ve been working in surround for about three years now, and I have to say that I truly love the experience. When asked my opinion, I usually recommend that studios begin to educate themselves now by experimenting with whatever kind of system they can put together. Mismatched speakers, an analog mixer pressed into service, whatever will work, just sit down and begin learning the process, figure out what works and what doesn’t, and experience the possibilities. It’s a blast, and will likely pay off in the future as surround becomes more prevalent.