Adcom gtp-500ii just died. What do you recommend?

trans am

hi friends, its been a while since I needed your help. I noticed a few weeks ago my left lsi7 was not producing sound. so to troubleshoot I took the left off and plugged it into the right speaker cables and it worked fine. so i knew it wasnt the speaker. so maybe its the power amp since I have them both running off a GFA-545II but i dont have another preamp/receiver that has a power amp out.
So the next thing I did was plugged the 2 lsi7 into the onkyo TX8522 2 channel receiver and both speakers work. so then I plug the gtp-500II preamp into the onkyo and run a 1/8 in to rca into the cd input on the gtp-500II preamp and the output from the main outs on the gtp-500II preamp into the cd in on the onkyo and both speakers work. so i guess its the power amp(GFA-545II) that is causing the problems. lemme try plugging the amp into the tape out on the onkyo and see if its the culprit. I hope its not the amp cause i love that thing.

trans am

well its definitely the power amp. Crap! that was a really nice amp. any suggestions for an upgrade?

audiobilly

I think the series II stuff has fuses on the rear panel for the plus and minus output rails. There should be 2 fuses for the left amp and 2 fuses for the right amp, and 1 fuse for the AC volt input. If that makes any sense. Check all fuses on the rear panel. An ohm meter would be the best. Or you can try moving them around and see if the problem moves. Note the value of the fuses when you take them out, and where they came from so you can track what is good or what is bad.

If there is no more than one fuse on the rear panel, then they are inside.I do not know how far you want, or can, go into this problem. Unplug the amp and let it sit for a few minutes. Take the top cover off. Look inside on the printed circuit boards that are next to the heat sinks. You will see 2 fuses on each circuit board. Check these fuses, out of circuit. Pull them out, very carefully. An ohm meter would be the best, sometimes fuses will fail at the connection on the end cap, they will look good but are open. If you are this far with out a ohm meter and can not see anything wrong with the fuses, swap them around and see if that side of the amp will work and the other side does not.

If the fuses are good, and checking them was a task, then a upgrade would be in order.
Or you could have it looked at. Or you could just Karma that baby!

Hope that was to to much.:)

trans am

I forgot to respond to this thread. I took the cover off and swapped to some new fuses. 5.00 and what do you know? its like brand new. I think I accidentally blew it with the wrong pos/neg connection. It was low light and these nakamichi banana plugs are very hard to read in low light. Now I have a new dilemma. recently bought a marantz 5005 and to replace the 4002 I had in the bedroom theater rig. So I moved the 4002 to my living room as my 2 channel rig to replace the onkyo because the onkyo didnt have the preamp outs and the martanz does plus the marantz sounds so much better. then I noticed the marantz doesnt have phono amp so I cant use my techniques record player. Why would a company like marantz that makes music sound so amazing not make phono inputs? this is so frustrating. I have a adcom gtp-500II and that has the phono in. I want to use the gtp-500II and connect the phono to that and run that into the marantz and it works but the problem im having now is I have my speakers at my computer desk are 8ohm rtia1 and my main speakers are lsi7 so the rti a1 are much louder than the lsi 7. what I used to do was run just the lsi7 off the adcom set GFA-545II/gtp-500II and run a signal out into the marantz off the velodyne crossover to power the rtia1 set. and I could independently turn the rti to match the lsi.

Big Dawg

I'm not sure - is there a question somewhere in there? You can get a phono preamp for anywhere around $20 up to well into the $1,000s.

dorokusai

Always check the fuses in Adcom gear since they use too many of them. I've bought a cool dozen amplifiers that were "blown" only to find it was a fuse.

Get the matching phono pre-amplifier dude....start yourself up a nice Adcom rig.

trans am

hey guys. this new thread I made explains everything.
http://www.polkaudio.com/forums/showthread.php?p=1629593#post1629593