ADCOM GFA-7500 Amplifier Service Manual - diyAudio
Go Back   Home > Forums > Amplifiers > Solid State
Home Forums Rules Articles diyAudio Store Gallery Wiki Blogs Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Solid State Talk all about solid state amplification.

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 15th September 2015, 01:27 AM   #1
dblack4 is offline dblack4  United States
diyAudio Member
 
Join Date: Jun 2005
Location: Newark, CA, USA
Default ADCOM GFA-7500 Amplifier Service Manual

Hi,

Anyone out there have the Service Manual or Schematic for a ADCOM GFA-7500 five channel amplifier? Thanks..
__________________
Is that right!
  Reply With Quote
Old 21st February 2017, 02:16 PM   #2
diyAudio Member
 
ampexperts's Avatar
 
Join Date: Feb 2014
Location: New Milford, CT
I need one too. Any luck?
__________________
Mark A. Weiss, P.E.
www.ampexperts.com
  Reply With Quote
Old 22nd February 2017, 10:50 PM   #3
dblack4 is offline dblack4  United States
diyAudio Member
 
Join Date: Jun 2005
Location: Newark, CA, USA
No, I did not have any luck but I did repair the amplifier. Dis-assembly was challenging..
__________________
Is that right!
  Reply With Quote
Old 23rd February 2017, 01:42 AM   #4
diyAudio Member
 
ampexperts's Avatar
 
Join Date: Feb 2014
Location: New Milford, CT
I'll bet, given 5 tons of crap in a 2 ton bag. :-) I recently repaired a Sherbourne 7 channel amp that had literally 1/4" of space between channel module heatsinks. That was NOT fun to work on. And 115lbs to lug around, too.
__________________
Mark A. Weiss, P.E.
www.ampexperts.com
  Reply With Quote
Old 24th February 2017, 05:33 PM   #5
diyAudio Member
 
ampexperts's Avatar
 
Join Date: Feb 2014
Location: New Milford, CT
If I may ask, what tool did you use to remove the 5/16 nuts holding the module to the speaker binding posts? I've gotten that far, but can't find a socket just small enough, but deep enough to accept the length of the rod on that post. My deep socket is too long to fit in that space. How did you disassemble and reassemble that?
__________________
Mark A. Weiss, P.E.
www.ampexperts.com
  Reply With Quote
Old 24th February 2017, 06:47 PM   #6
dblack4 is offline dblack4  United States
diyAudio Member
 
Join Date: Jun 2005
Location: Newark, CA, USA
Sorry I don't remember the size of the wrench I used.
What do remember is the amp needs to be turned upside down. Disconnect wires to small AC pcb mounted to bottom of case or remove mounting screws. I don't remember which I did. Watch out for washers and such. With the top cover and ALL screws installed turn amp upside down and remove bottom cover. Now use wrench to un-tighten bottom speaker post. Do the other also if possible. Re-install bottom cover leaving out the individual heatsink screws. Turn amp over, remove top cover, all back screws, disconnect amp wiring. Un-tighten last speaker post. All this is easier to do with one amp module removed so reinstall is easier. I may of forgotten something but you get the idea. I sold the amp some time ago.
__________________
Is that right!
  Reply With Quote
Old 24th February 2017, 07:25 PM   #7
diyAudio Member
 
ampexperts's Avatar
 
Join Date: Feb 2014
Location: New Milford, CT
Okay, so there is no shortcut. I was concerned that a complete teardown might be the only way to do this. Just to get two modules at opposite ends out.
Thanks for detailing how you did it. I have to figure out the hours and let the customer decide if he wants to go forward with the repairs.
__________________
Mark A. Weiss, P.E.
www.ampexperts.com

Last edited by ampexperts; 24th February 2017 at 07:28 PM.
  Reply With Quote
Old 26th February 2017, 04:14 AM   #8
dblack4 is offline dblack4  United States
diyAudio Member
 
Join Date: Jun 2005
Location: Newark, CA, USA
I understand your thought process on this one. Looks like allot of work. I let the amp sit for weeks as I thought, do I really want to do that much work..... Once I found the right wrench it was way easier than I thought. My apologies, I thought the heatsinks were screwed to the top cover as well, a different amp I guess... Perhaps I installed the bottom front heatsink screw for each amp. Then lifted the front of the amp to remove the screw. This avoided the problem of the dangling module when upside down. To reinstall, I supported the modules with a book/mag or something like that while I tightened the speaker posts. I think you'e going to need to remove all the modules.

Anyway, I recapped the whole amp and some other bad parts.
__________________
Is that right!
  Reply With Quote
Old 26th February 2017, 03:14 PM   #9
diyAudio Member
 
ampexperts's Avatar
 
Join Date: Feb 2014
Location: New Milford, CT
Either way, it's a lot of work several hours at the least. Not to mention the actual troubleshooting and repair of two failed modules and this unit. The customer doesn't want to spend more than $300 total and it's going to come to weigh more than that with all this disassembly so I think he's probably going to opt to just buy a new amplifier. It's a shame, but he's 77 years old and probably doesn't want to spend money on a repair without having at least a five year warranty.
__________________
Mark A. Weiss, P.E.
www.ampexperts.com
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Recommend anyone in UK who can service/mod my Adcom GFA-535?? Salli Solid State 2 26th March 2015 11:57 PM
Adcom Gfa 565 Amplifier Service Manual bainesni Solid State 9 19th February 2015 02:07 PM
Error in Adcom GFA-555ii Service manual K-amps Solid State 29 4th June 2013 03:32 AM
Adcom GFA-555 II Manual Funkenstein Solid State 0 30th April 2007 01:11 PM
Adcom GFA 7500 channel problem G-Rock Solid State 2 19th May 2005 02:09 AM


New To Site? Need Help?

All times are GMT. The time now is 07:46 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright 1999-2017 diyAudio

Content Relevant URLs by vBSEO 3.3.2
Wiki