Sir, how do I change the power input of my Adcom GFA 555 from 120v to 230v. The amp is dual voltage rated. Thanks.

SOURCE: ADCOM GFA 5802 POWER AMP NO SOUND, BUT POWERS UP.

It was funny to read this post because this amp has MOSFET output transistors, so there is no BASE and it is difficult to test them by the meter. Also the amp has huge power capacitors @+-80 volts rail and any experiment like "lifting the base" could cost you burned board or $250 in parts per channel. I think the best way is to bring it to an repair shop.

SOURCE: can you bridge an adcom GFA-5802 power amp?

Running an amp in bridge mode requires a specific circuit design. It is not possible to combine 2 amps in this fashion.
Dan

Scott Frye

• 1175 Answers
• Posted on Mar 25, 2009

SOURCE: Adcom 7500, Adcom 5400(bi-amp), Marantz AV-9000, Dakiom HA103

Try just the power amp on ..nothing connected
no Dakiom thingy either. It's a matter of elimination. Start at the output device and work back. Keep the Dakiom out of the loop.
If there's hum with just the Adcom..then it's the ADCOM

SOURCE: how do i bridge an adcom gfa 5400

This amp is not designed to be bridged and can not be used in the mode you wish. Sorry, but internal circuit changes would be necesary for the amp to work as a single channel.

Dan

SOURCE: Adcom GFA 555

Lakes Electronics, Inc.
5245 N. University Dr.
Lauderhill, FL 33351
United States
954-749-6100
These guys are listed as one of the 2 Adcom service centers in FL and should be your best bet.
Also Jason Schatten @ Electronic labs might be able to help. Electronic Laboratory, Inc.
1301 West Copans Road, A4
Pompano Beach, Florida 33064
Phone: (954) 969-2855
Fax: (954) 969-2879
Email: [email protected]

Hope this helps. Parag