UREI Model 1178 studio compressor channel issue

[blindboybenton]

Hi to you all

Happy new yr

I have an old 1970's/80s studio compressor

The guy told me that one channel was lacking in freq responce
On checking one channel was lower output and lost its bass and and compared to the other channel

I decided to change all the caps and for good measure the op amps . The caps looked old and tired and customer really likes this.
UREI-1178 manual.pdf

After changing caps and op amps Ic 1/2/3 and Ic 7/8 Still the same
Psu is ok and correct
I have a scope and an old signal gen, Tried a cd input and the signal gen

with my limited knowledge of electronics im not sure where to go now.

can anyone shed some light

Bassman

[Jazz P Bass]

You have a working channel, no?

Compare the two to find where in the circuit the signal is failing.

Do any controls affect the problem?

Does selecting Stereo or Mono mode have any affect on the problem.

[blindboybenton]

Hi Jazz bass

None of the controls make a difference nor does the mono/stereo s/w
Channel A is good
I will have another look again later today

Many thanks
Bassman