Is there something wrong with my Adcom GFA5500?

[Rhadamanthus]

It seems to run hot. I'm comparing it to my Mcintosh MC7270.

Tonight I fired up the old Adcom and let it idle, nothing else
turned on, no pre-amp, CD player, nothing. After one hour, it was up to
120 deg. F.

Sound like a problem to you guys? I bought it drand new about 10 years ago. It has never been messed with. Has a soft turn off thump on on channel.

The Mcintosh barely get warm even after hours of use.

I guess I'll busting out the watt meter and see what it's pulling at idle. Then, as someone else suggested on another post, the scope.

I'll look at the output and see if anything shows.

[Blvdre]

It may or may not be a problem. Does it run hotter than it did when you bought it? Is it getting proper ventilation? The Adcom website sates that the front end of this amp is run class A (hot) - didn't specify the output stage operation, but it may be A/AB, maybe not. A lot of people also overlook blowing the dust out of thier equipment - it's amazing what can accumulate. Maybe the output devices need to be re-biased.

[djk]

"The Adcom website sates that the front end of this amp is run class A"

Did they also claim it ran on electricity?

I've never seen an amplifier that front end didn't run class A.

120°F is fine, won't hurt a thing. I wouldn't worry about it unless it ran over 150°F at idle.

McIntosh bias proceedure:

Operate MCxxxx at 120 volts line input with no input signal. Measure the input power (approximately xx watts) or current (approximately 0.xx amps).

a) Turn both bias potentiometers full ccw.

Rotate bias adjustment cw to the point where the line input power of current begins to increase then back off slightly to the point where the line input reaches its lowest value.

c) Repeat step b for each channel independently.

(in other words, optimal class B bias)

In general, it's kind of hard to tell they're even on (when idling).

[Blvdre]

.

"The Adcom website sates that the front end of this amp is run class A"

Did they also claim it ran on electricity?

I've never seen an amplifier that front end didn't run class A.

[:$] Rubber bands and hamster power.

[Rhadamanthus]

Sparked up my Watt meter. My Adcom uses 125 watts at idle. Mcintosh, 47 watts. Anybody else have an Adcom and a watt meter?

I'll have to find the manual that came with it, I believe it listed power comsumption.

Found the paper work that came with it. It lists the power consumption at quiescent as 192VA and full load 1440VA, so I guess the 125 watts at idle (quiescent) is about right.