stevem Messages: 4733 Registered: June 2004 Location: NY
Senior Member
If you mean the jacks marked power amp in and out and not switch than this is there function.
These jack break open the signal feed out of the preamp that than goes to the power amp in normal operation.
If you plug a cable into the the jack marker output you than have the signal from the preamp section that can be fed to a recorder and or a different power amp.
The jack marked output will allow you to use the power amp by feeding a different preamp signal into it to drive it, but in this mode you cut off the internal preamp signal from passing to the power amp.
In regards to the switch it should be marked polarity and it's function is as stated in the preceding posting.