Tech Tip:Audio Compression

By Dennis Kambury


Compression is one of the staples of virtually every recording studio, from basement demo stations to world-class super-studios. But just what do you do with it? Here are five ways of using compression to squeeze the most out of your music:


1) Tame the wild vocalist. By adding a bit of compression on vocals, you can both make up for a singer's tendency to move close to or away from the mic, and to temper the occasional peaks that might otherwise overload your recording medium. This is especially important for digital recordings - digital clipping will irreparably ruin a take in an instant!


2) Add sustain. Guitarists know this one well - by adding compression with a long release time, you effectively lengthen the tail of the signal. On attack, the peak is squashed, and as the signal decays, the compressor opens up, allowing more of the signal through. Don't limit yourself to guitars, though. Play around and see what works.


3) Add punch and clarity to the bass. By reigning in the bass signal, a compressor helps give the sound definition and power. When you really want your bass line to stand out, a healthy dose of compression may be just the ticket!


4) Special effects. One of the hazards of compression is that the lowering and raising of volumes can lend a breathing or pumping sound to the compressed track. However, if you like to live on the cutting edge of composition, this can be used to good effect (pardon the pun!). Get a good rhythmic groove going that really works the compressor, and experiment with the results.


5) Compress the entire mix. By adding high-ratio compression (or limiting) as you mix down to stereo, you increase the apparent overall level of your tune, and give it maximum punch. But beware - too much of this can completely suck the dynamics out of your music, leaving it loud but lifeless!

So what do you need to get started? Musician's Friend has dozens of solutions, but here are some of my favorites from across the price range:


For high-end quality, the Avalon VT-747SP is the way to go. It's not inexpensive, but its outstanding tube/discrete design, attention to detail, and painstaking construction all add up to one amazing piece of gear.


Supporting the mid-range price zone, the Joemeek SC2.2 and dbx 1066 provide pro-studio grade compression using discrete technology to keep the costs down. Both are recognized leaders in the world of studio compression.


For the budget-minded, you can't go wrong with the PreSonus Blue Max. At under $150, you get a half-rack space mono compressor that lets you go fully automatic with built-in presets ideal for those new to compression. For the already-initiated, full manual mode lets you work compression magic to your heart's content!


Whatever level you choose, these sonic tools will always have a place in your rack, as each compressor adds its own unique signature to the sound. Try 'em and see!