Looking for info Adcom

[Heiney9]

I recently aquired Adcom GCA-510. It's Adcom's version of an integrated amplifer which was marketed mostly to the UK to compete with the likes of NAD, Rotel, Denon, etc. Audiogon shows a production date of 1998. It was a very short lived product for a specific market.

It sounds fantastic I've been told it's essentially the 535 amplifer section with the SLC-505 line stage control. Adcom calls it "a control amp" in the literature.

Also from the literature:

It offers the convenience of an integrated amplifer but it is a very high gain power amplifier preceded by a passive level controller. There is no seperate preamplifier stage in the GCA-510 at all.

The circuit topology includes a two stage discrete front end with a doubly regulated and temperature compensated active constant current bias sources.

The output stage utilizes a unique Bias Emitter Multiplier to amplify a transistors inherent silicon junction voltage to create a temperature compensated constant voltage source. The complimentary output stage features discrete high power devices operated in high bias Class AB Common Collector Mode.

This design employs no current limiting. Precise speaker control is furthur assured by the intentional elimination of output coils to provide a constant high damping factor.

Anyone have any info on this somewhat rare Adcom piece? My main question is since it was manufactured in 1998 how can I tell (no schematic avail) if this is a Mosfet output stage or Bi-polar. At this time Adcom was using Bi-polars for the multi channel amps and Mosfet's for the 2 channel amps.

This thing is dead quiet and sounds quite a bit more powerful than it's rated 50/75 wpc @ 8/4 ohms. Typical Adcom build quality and circuit design. 700mV torrid transformer w/ (2) 6600uF bypass caps per channel and 4 output devices per channel (from memory when I had the top off).

Anything you can add about this model is appreciated.

H9

[EchoWars]

Call up Adcom...they'll sell you a schematic.