AltoComp is a 1U, two-band dynamics processor. Despite its low cost, and the maturity of dynamics processing in general, it manages to spring a few surprises.
I/O is stereo XLR balanced line-level, with MIDI in/out/thru. Sixty-four factory presets cover common processing applications; 64 user slots are also available. The interface consists of a 2 x 20 character backlit LCD, accompanied by seven programming buttons and controls for input and output level. These stick out quite a bit from the panel, but the knobs are recessed to minimize the chances of snapping them off — smart move.
The dual-band processing is unconventional: Each channel splits at an adjustable crossover point, with the lows going through a limiter and level control, while the highs have adjustable level only. The recombined signal then feeds a conventional compressor. This design favors boosting apparent volume as unobtrusively as possible rather than being an “effects” compressor. In fact, most presets are oriented toward program material, although I also achieved fine results on individual tracks. Furthermore, a switchable AGC (automatic gain control) “front end” is ideal for live use to even out incoming level variations.
As a bonus, just about everything can be MIDI-controlled.
What’s not to like? The manual tries to be useful, but glosses over some crucial aspects (e.g., compressor attack and decay are calibrated in “dB per second” instead of ms). Thankfully, ART says it’s being rewritten. Meanwhile, it’s good the presets are useful, because unless you’re a dynamics processing veteran, you won’t be able to figure out how to take full advantage of the AltoComp’s clever features.
AltoComp isn’t a “master of all trades” box, but excels as a quick, easy, inexpensive way to add a solid “lift” to recorded tracks, program material, or in live performance. Hear it for yourself. It shows how low-level signals can be emphasized without side effects or artifacts.