headroom not what it used to be

[gang of elk]

today i'm noticing less headroom and less beefy low end from a pr of calrec comps. they were in storage for years before i got them working a few months ago. only in the last week have i been using them for hours at a time. i guess it's possible that in the excitement of getting them racked up, my brain overlooked this problem until recently. right now i'm hearing distortion on some lo-mid program material during compression but not when the threshold is raised sufficiently to let the signal pass thru uncompressed. distortion does not appear to be a function of attack or release times. could this be a cap issue? a vca issue (dbx 2150A)? first thing i checked was the PSU, i'm seeing +16.05v/-15.9v. could this lack of symmetry be complicating matters? any thoughts appreciated..
-scott

 

[owel]

Should it run on +/- 18? Low supply voltage will result in less headroom.

 

[gang of elk]

the schematic says +/-16v. i increased the psu to +/-18v to see if it would make a improvement and it didn't. so now it's back to 16v. i think i have enough spare nichicons to replace the electrolytics so i'm thinking of doing that tomorrow.