I'm curious as to how pre-outs in a receiver work. I was expecting something in a menu somewhere to enable the pre-outs but it seems not.

Does this mean that there is always a low level signal applied to the pre-outs? Are the pre-outs on a common circuit with the one that supplies the signal to the internal amps?

I noticed in one of the newer Denon manuals that it tells you not to connect anything to the pre-outs while you are using the main speaker outs, but it does not explain why.

Inquiring minds want to know...

Just based on strictly anecdotal information and having used AVR's most recently with outboard power amps, I am assuming there must be some sort of common signal(low level perhaps) with the option of plugging in to the pre-outs which automatically shuts off the internal amplifiers. The AVR then turns in to and pretty much acts like a stand alone pre-pro. I am not exactly sure why Denon would mention the warning of having speakers hooked up since the power would shut off immediately to those speakers the instant you plug the pre-pro connection in to an outboard amp.

In my opinion, good AVRs sound excellent with outboard amps and having tried both stand alone pre-pros and the AVR/pwr amp combination, I have never subscribed to the "theory" that stand alone pre-pros sound noticeably better.

Fred, "applied" wouldn't be quite the way to describe it. The arrangement can be looked upon as an internal "Y" from the pre-amp, with one branch for each channel sending voltage to the built-in output transistors for that channel and the other branch going to the pre-out. If the pre-out isn't connected to anything, no voltage is output there. No apparent reason for the Denon caution, since sending voltage to both the internal output transistors and out the pre-out to an external amplifier shouldn't cause any problem.

Thanks gents. John. Your description is more precise, but thats what I meant. Interesting. I could actually set up 4 zones with this receiver using the B channel pre-outs. Hmmm. Livingroom, bedroom, kitchen, bathroom...