Adcom preamp repair -- advice needed

[IshMEL]

Hi all,

I have an Adcom GTP-400 preamp that I need to get repaired. (Output on left channel is intermittent / scratchy.) Does anyone have advice on where I should take it (or send it) for repair? I live in NYC and so I could take it to one of the authorized places listed on the Adcom site, or I could box it and send it. I was hoping for a recommendation for a reliable and cost-effective repair shop.

Thanks for your help!

 

[nigelwright7557]

Why not have a go at fixing it yourself ?

A pre amp is usually easier to repair than a power amp as a power amp is a loop.
You can follow a signal through the preamp until it disappears or you find a DC fault.

 

[DCPreamp]

I agree with nigelwright7557. You very well may be able to fix it with never touching a soldering iron or pulling the PCB from the chassis.

An intermittent / scratchy channel is likely a dirty pot, switch, or RCA jack. Pick up some contact cleaner (mail order or Radio Shack), spray the volume/balance pot and all switch contacts. After spraying, run the pots and switches full-sweep from stop to stop to fully wipe the contact surface. Also look at the RCA jacks closely looking for the center contact to have deformed, loosened, or backed out. Needle-nose pliers can often fix that.

You'll very likely fix it and learn something too. If that doesn't work, check back here for more options.