Well... ya kinda came to the right place. The 1968 was a version of the 1969 without the microphone amplifier section... and the 1969 was designed to my "specifications", for my sense of aesthetic [in a previous life, I used to run Mercenary Audio].
As a "drum buss" compressor its a pretty bad assed box. Between the "attack" and "release" functions [along with the "hi-pass filter" on the "detector side chain"] you can get some very explosive drums that don't have that kinda signature "haze" that I hear on way too many recordings.
The "time constants" on the "attack" and "release" were the part where the greatest amount of tweezing time was spent. On the "attack" side the time constants go from short to long over 6 different settings... on the "release" side the time constants are split into two sections... 1 is fast, 2 - medium, 3 - longish... 4, 5, & 6 are kinda the same but they're "program dependent" which I find can work really nicely for 2 buss work... for drum buss applications I prefer release options 1, 2, or 3.
The switchable "hi-pass filter" on the "detector" circuit [the part of a compressor that tells the actual compression amplifier just how much to turn down the volume] is there to keep things like the kik drum from modulating the compression. This is an especially good feature for 2 buss work as it helps you keep the overall compression signature from sounding like the music is breathing around each kik hit so the compressor can focus on what is usually the next loudest element of a mix -- the vocals.
If you decide to give the unit an audition the starting point I would recommend for program material [2 buss] is attack 4, release 4 with the "big" [detector hi-pass filter] engaged... for drum buss work, attack =4, release =1 and again, with the "big" switch engaged.
Whether any of this will suit your sense of aesthetic for the music you're working on is going to be very much up to you and the production team... for my work... well, the box was built for the things I like to hear in my work so obviously the '68 was a favorite in my arsenal.
Hope this is of some assistance.
Peace
