Grommes G8A Attack/Release Question

[Icegoldnixon]

Hi folks. I have had this pair of G8A "Automatic Volume Limiters" from Grommes, and finally had them professionally repaired.

They really sound amazing, dead quiet, with everything sounding better just going through it. The limiting is also pretty nice, but it has a characteristic that I'm posting this thread to ask about.

When first going into limiting, it has a tendency to massively overshoot and clamp the volume down very noticeably. It will then stabilize and more gently ride the peaks. But this aggressive kick-in is a bit of a problem, as I really have to keep it in GR to avoid the overshoot. Would this be expected behavior based on the schematic? Could anything be changed/modified to avoid this? Thanks!

 

[Icegoldnixon]

Sorry to just bump, but any insights here? Is this behavior common in vintage broadcast limiters?

 

[emrr]

It's common, it's changing to a compression state. You can possibly set input gain against threshold so there's less noticeable change when it kicks in. The overshoot is the period in which the timing cap is charging up, before it can deliver a steady control voltage. Most ancient broadcast compressors were not meant to do more than about 3dB limiting.

 

[Icegoldnixon]

Would there be any way to keep that capacitor charged?

 

[emrr]

investigate the hold switch used on the RS124, something like that as a "pre-charge" option might work.