Hacking a Denon AVR-1804

[OrganicBud]

Howdy guys,

My dorm mates and I have a decent, rather random hifi setup in our room, consisting of 4 Bose 601 III and a peavey bass amp as some kind of evil woofer, all being driven by a Denon AVR-1804... all fine and dandy until my acquisition of 5 Marantz MA-500s. I want to be able to use the DAC in the Denon for our optical inputs, and the plain preamp for analog inputs but the Marantzs as our actual amplifiers, again with the Denon as our volume control. As the Denon was never meant to be used as a preamp, I am stumped. I am rather good at things like this (admittedly... tube stuff though), so fabrication is not an issue. Any other cheap (note: college student solutions are welcome.

Thanks!

[SQLGuy]

I assume you don't have the schematic for this unit.

If you have a scope, I would say to feed the unit a test signal, like a 1KHz sine wave, then trace the output circuit back - outputs to drivers, drivers to VAS, VAS to input (of the power amp section), and see if you can find a reasonable preamp signal there (probably going between 0 and 2V AC by the range of the volume control... maybe a bit less). That signal may have a DC offset that would need to be removed with a coupling cap, but you could tap it out from there (and for the other channels from their corresponding points) to add pre-outs for the receiver. You probably want to add a switch and maybe an extra load resistor, to allow the signal to be removed from the receiver's power amp when the signal is being fed out the pre-out.

[derguteton]

AVR-1804 servicemanual at mmm,freeservicemanuals,net

for 5 days, good luck