Adcom bias setting

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

Remove the output transistors and measure each of the sets of 3 pads and report the voltage readings here. I suspect that you have either a blown driver circuit or output transistors. The voltage readings will give me an idea on where to start looking for specifics.

Thanks,
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: 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

SOURCE: Adcom GFA 5500 right channel emits horrible sound.

Adcom makes a great amplifer! Usually broken highs and no bass means blown speaker. Try hooking it up to a completely different input source. Try different speakers also. If problem persists, check the fuse. Most will have a fuse on the back you can screw out. Some have two fuses (one for each channel) If this doesn't fix the problem it could be expensive to fix. Also, does this model ave the thermal protection light and if so, does it come on at all?

Grubhead

• 5755 Answers
• Posted on Oct 19, 2009

SOURCE: adcom gfa 555 blows the 10 amp fuse and the 6 amp

Any fuse blowing is caused by a shorted component in either the power supply section or main audio amp part. Follow the fuse circuit and see where it leads you. Look around for burnt of damaged parts. Suspect anything sitting on a heat sink. The most common culprit is the audio amp main transistors, especially if someone shorted the speaker leads together. In the power part it could be the transformer, the large Electrolytic capacitors, rectifier, or voltage regulator. Some amps use an IC for amplification and this can blow the fuse.