hi fabio,
i stand corrected. it wasn't actually a post in a thread that i remembered keith's mention of the necessity (or rather lack of) for the SC pcb, but rather in the manual (which you should really read in full prior to installing your turbo pcb).
here is a quote from the manual (hope this is o.k. with keith):
Installation with ‘High-pass’ Sidechain boards: (optional)
There have been a couple of lof-frequency rolloff boards designed for the GSSL as attempts to ‘fix’ the GSSL’s tendency to over-compress loud, centre-panned
instruments. These can still be used with the Turbo, however you’ll need TWO
channels of high-pass filter board. Also, a dual-gang switch should be used, so that the rolloff selector switch now controls BOTH channels simultaneously.
–It’s worth considering however, that the need to use a low-rolloff may be quite
considerably reduced once the turbo board is fitted, since the original design’s dualsidechain circuit (which was omitted from the GSSL version) is considerably less sensitive to being influenced by the typical centre-image ‘problem’ sources, such as kick drum, bass, and loud solo instruments.
if you want all the bells and whistles, then by all means use the SC or SSC pcbs that are available, but you will need two to work with the turbo mod.
regards,
grant