Tube-Tech says their optical compressor is smooth and musical. Well, it works on music, so I guess it’s musical. And it’s a compressor, so I guess it’s smooth. OK, I apologize. I am fascinated that a whole alt-vocabulary has developed around describing what sound sounds like, or even better, marketing what sound sounds like. Can anyone say “adds warmth”? (Yes, “warmth”—less high end.)
Anyway. The CL 1B works really well on the 2-Bus, probably because it tones down all the high-end (which seems to build up with digital sources) even before it starts compressing. (You know, it adds warmth.) On vocals it can really do a lot of gain reduction without sounding unnatural.
(And it adds warmth.)