Computer Audio Pt 3....audio interfaces.

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Notice I don't call them "soundcards". What you're looking for is more than your typical Audigy. For a gaming machine, your choices will be based on audio output, surround capability, and decoding of game sound. These cards are fine for that job, but fall far short of what's needed for true recording. If you were thinking "I'll toss that Audigy 2 Platinum in my machine", forget it. Go grab a beer and read on.

Currently, there are two forms of pro audio interfaces: One uses an inboard PCI board as a bridge to an outboard unit, and the other uses either USB or FireWire, and are self-contained. For example, Pro Tools uses a PCI based card (or multiple cards) to hook proprietary hardware to your machine. M-Audio's Delta series also uses PCI cards. How these differ from your run of the mill gaming card is in the construction. These cards don't actually do any sound processing, they simply act as a D/A converter. M-Audio has a budget Delta soundcard, but I don't recommend it for any serious applications. While these card/box combos are nice, and work well, they're limited to the speed of the PCI bus.

The other option is becoming more prevalent........completely outboard units, based on USB or FireWire. These have two tremendous advantages: The power supply is completely seperate from the host machine, and the size restraints are gone. While you only have a small space in which to put circutry on a PCI card, an outboard box can be as big as it needs, use as many boards as it needs, and be RFI/EMI shielded. Of these, I prefer the M-Audio FireWire series, as they use the 400/800 bus available, bypassing the PCI bus completely. (Noise issue again)

These boxes will typically include not only a pair or two of midi ports, but also high quality mic preamps. Most units today are using Neutrik combination jacks, which accept both 1/4" balanced/unbalanced cables and XLR balanced mic cables. Good units will include two of these, with a minimum of 8 balanced 1/4" jacks either on the back, front, or split between the two. These will also include discreet headphone monitoring capability, some patchbay capability, and phantom power for condenser mics. In the case of M-Audio's stuff, more mic preamps can be added via ADAT LightPipe, for clean signal and high speed. Pro Tools also uses LightPipe connections, but are limited to their own hardware.

Note.......5 years ago, Pro Tools was the way to go, for many reasons. Today, the M-Audio line is just as good, if not better, due to the flexibility of the system. Cost is also alot less, so I'm focusing more on that line of gear, for that reason. Pro Tools can cost $20,000 for a well-planned studio.

Now, here's the main difference between a pro-level sound interface and the de-facto Audigy: Recording capability and latency. Outboard gear, like Pro Tools or M-Audio, record at 24/192 levels......the Audigy only records at 16/128. The difference is night and day. Believe me, if I could use an Audigy, I would.......this stuff can get expensive! However, it's just not an option, any more than playing Half-Life 2 on an MX400 is a true option for you gamers.

The final benefit is the power supply. Since the outboard box you choose is totally removed from the computer power stream, you have no noise from CPU cycles, unshielded power traces on the motherboard, and drive noise. Even the lights on the optical drives create some noise, believe it or not. Removing your inputs and outputs totally eliminates that problem.

Using an outboard box offers you another benefit: Mobility. Rather than being tethered to a desktop PCI card, you can take a FireWire based unit on the road, plug it into your laptop, and record your band live.

Where these outboard units really shine, though, is latency. Latency is defined as the time it takes a signal to go from input to output, and needs to be minimized as much as possible. I'm a drummer, and obviously, I'm very concerned about timing. Say, I record a series of tracks, and want to overdub a different snare sound. With a high latency, even just 10ms, it'll drive me crazy trying to hit the beat just right with the recorded sound. If I can do it at all. Pro-level audio stuff reduces this latency to the minimum (less than 2ms), but it is dependent on your machine. You'll have to tweak the software to get the lowest possible latency without distorting the signal.........but more on that in a later post.

The final piece of this puzzle is the monitors you choose. No, your prized 680's won't do the trick. They color the sound, and are designed for finalized music playback. While I'd suggest using them to listen to your final mix, DO NOT use them for monitoring during recording. Your mix will come out sounding like an AM radio. You'll want to look for a pair of studio monitors. The idea behind these is twofold: They're nearfield, meaning that the "sweet spot" is about 24" in front of the speakers, and they're extremely flat in response. Don't expect massive low end, nor sparkling high end........what you're looking for is an exact replica of the sound recorded by your mic. Since consumer speakers vary wildly in frequency response, efficiency, and overall tone, if you record and mix your song listening through your favorite home speakers, the finished mix will sound killer to you, but to somebody who has a pair of $100,000 Nautilus speakers, the mix will sound like absolute crap. Mixing requires a flat response........as close to totally flat as possible. Top monitors right now are the Yamaha NS series, Mackie's active monitors, and M-Audio's series of monitors. All are good, let your budget decide which is best for you.

The final things to have, as far as hardware goes, are some listening options. I use a few things........a set of Infinity tower speakers, a pair of Audio Technica headphones, and my car stereo. When it sounds good on all three, then I know I'm done.

Last bit coming up later........software.
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