Originally Posted by Spectrephonic
The real units are often used in chain on vocals, just because they do different things. Mostly 1176 (FET) -> LA-2A (RE-2A). 2 compressors in chain can be good because neither have to work too hard.
Yep! The Opto's slow attack and non-linearity coupled with FET's fast attack can produce great results. I often use them on basslines, sometimes O>F, other times, F>O.