The most effective preset I have come across for emulating a Tube-Tech CL 1B with optimal vocal settings is the Drum Bus preset, with a minor increase in the low frequencies by around 1 dB.

Vocal Clarity = Moderate Attack/Slow Release
Vocal Focus = Slow Attack/Fast Release
Drum Bus = Fast Attack/Moderate Release
Bass = Fast Attack/Fast Release
Keys/Guitar = Moderate-Fast Attack/Moderate-Fast Release