Ya know, that's interesting that you should also want the compressor without the gate. I, myself, have been wanting to jump into this design sans gate.
If you regularly mix in the analog world then I'd recommend you build the gate and compressor together since the gate's sidechain uses the uncompressed signal while the compressor can be smashing the crap out of the signal independently... hard if not impossible to do with two analog units. AND both processes share the same VCA, so there's less signal path... pretty cool.
However, I gate in the digital domain when I'm mixing, and (with drums particularly) I regularly copy the track(s) to be gated to adjacent tracks and assign those output to the sidechain of the plug-in gating the other signal (thereby triggering the gate from an unaffected version of the same signal..... like the SSL design). For this reason I too am interested in only the compressor section. (It also makes for easier PCB layout without the gate portion).
I've got a buddy who does prototyping for Texas Instruments that I'm getting to help me lay this thing out, but it won't be for a few months at least since I'm working on several other things at the moment (racking six channels of Neve mic pre's, finishing my LA-2A, a line mixer for a friend, another SSL bus compressor, and a pair of tube mics).
THEN.... I'll get to it. If you have any progress on this, Cactus, please keep me posted. Otherwise I'll contact you when I start putting it together.
BTW, I was planning on adding the Peak/RMS switch that Keith mentioned. Keith, you told me once before how to accomplish this, and I remember it seemed rather simple, but I no longer have that post.
Could you go through it one more time for me on THIS forum?
Thanks, and peace,
JC