The MindPrint T-Comp Stereo Tube Compressor ($1,099) is a tube- and solid-state hybrid, soft-knee compressor that performs transparently on stereo mixes and acoustic guitar. However, it’s quite noisy and lacks the headroom to handle really hot pro levels. Just the same, the T-Comp is a good workhorse compressor for vocals, bass, and snare-drum tracks.

At the bargain end of the VCA price scale is the PreSonus Bluemax Smart Compressor/Limiter ($199). This fixed-stereo unit provides numerous compression presets, and it also offers a manual setting with which you can dial in attack and release times to taste. Despite its low cost, the Bluemax is one of the best compressors I’ve heard on kick drum. It also provides excellent control of acoustic guitar tracks.

Rubik’s Tube
Many engineers lust after the warm, round tones that great tube gear can deliver. Tubes—especially when driven hard—generally produce more even-order harmonics than solid-state devices and they also tend to saturate in a more gradual and pleasing way. On the other hand, the most pristine solid-state designs tend to offer a more focused sound and slightly better transient response (detail). Both topologies have their place.

Quite a few hybrid devices are available for purchase. Hybrid designs employ both tube and solid-state devices in their audio paths. The dual-topology Millennia TCL-2 Twincom lets you switch between completely independent all-tube and all-solid-state audio paths in the same box.

It’s helpful to know a compressor can be marketed as a tube processor and yet have a solid-state device—for example, a VCA or opto cell—in its audio path. Some purists insist a compressor is not “all tube” unless the gain control element is also tube-based (as in Variable-Mu designs), but that is not a practical concern. The gain-control element affects the compression curve’s envelope, which in turn can affect the sound’s timbre. But a well-designed tube output amplification stage can certainly give the lush timbral coloration and depth most folks are looking for in a tube device. For example, the Groove Tubes CL1S combines an opto element with a tube output stage, and that box has incredible warmth and depth.

On the other hand, just because a compressor has a tube in it doesn’t mean it’s going to give a fat sound. Just by listening to the Bellari RP583, for example, I would never know it was a tube compressor. Also, I’ve heard other tube units that sound more like distortion pedals than pieces of studio equipment. Generally speaking, you get what you pay for—and the best-sounding tube gear tends to cost a lot.

Interestingly, there are also quite a few solid-state compressors that offer wonderfully warm tones (the Empirical Labs Distressor and Joemeek units immediately come to mind). My advice is to judge each compressor, tube or solid state, on its sonic merits and try not to get caught up in the hype.

Ones and Zeros
One advantage of digital compressors is most of them offer “look ahead” circuitry. (Interestingly, dbx also offers an analog compressor with that feature.) Because the compression algorithm is in software, the compressor can analyze what it is about to process and place the attack time right at the onset of—or even before—the sound, resulting in a zero attack time. However, while a super-quick (or zero) attack time is great for catching transients, it doesn’t always sound the best. Therefore, use such power judiciously; the crack of a snare drum without any attack just doesn’t sound right.

BACK | NEXT

Reprinted with permission from Magazine, February, 2001
© 2001, Intertec Publishing, A Primedia Company All Rights Reserved