Preamps with two main-outs


Question for folks with two separate stereo amps driven by a single preamp. My preamp has two main outputs feeding two separate amps - one stereo and one pair of monoblocks, driving two pairs of speakers in two different rooms. Is it normal to need to turn on all the amplifiers to play any music? In other words, I can't just turn on my stereo amp to listen to music in one room. Its all or nothing. Fortunately the mono amps (MC2200) have volume control and I can turn them all the way down but can't do that for the stereo amp for the speakers in the other room. I was wondering if this is normal for all preamps with multiple pre-outs or its dependent on a particular preamp model. If it matters, the preamp is a NAD C165BEE. Thanks.

P.S. The second main-out has a little knob for gain control but its on the back of the preamp next to the ports and not practical to use for this purpose.

128x128kalali

With the amplifiers off, I measure "continuity" at the input ports on the Vincent but not on the MC2200, using my very basic millimeter. Didn't feel comfortable sticking my meter probes inside the ports with the amplifiers turned on. I think we can surmise this is NOT normal behavior and is dependent on the amplifiers' input stage design. Thanks everyone for your help in explaining this behavior.


Previous post should read "multimeter" not millimeter. Autocorrect in action...
I use to have an unusual set up, 4 monblxks driving the top and bottom ends of a Dutta Signature. Since they were identical I just bought a set of custom Y connectors. Worked fine but I doubt if few have a system like this.
My stereo pre-amp (Sachs DS-2) has two outs, with differing caps on each pair. I've no clue either as to where the coitus-interrupts electrons go if you just snaggle up to one pair, but Don Sachs' suggestion is: try both and if you're still befuddled, hook up a Y connector to each channel-out pair and see what happens.
Being of the tube world, for me, output impedance is always a concern. Are you piping into a 300K ohm amp input (tube) or a 10k ohm sand amp.
Hi,  well I have a boutique high end preamp with two sets of preamp outputs.  It is basically an analog tube preamp made from Audio by Van Alstine.  It's feeding two main mono blocks V4's and a separate pair of mono blocks Silver 60's for the rear speakers.

They are made by Quicksilver Audio.  Because my preamp does not have digital processing for surroundsound, I'm using what would be considered an old style five channel home theater system made by Dynaco. It's called the QD-1 series ll L.

I also have a sub and center channel. The V4's are wired to the main front speakers as well to the QD1. From the QD there are speaker leads to the rear amps that allow me to use the front V4s for all speakers or the rear amps wired to the surrounds as well