Can I rig a home theater amp to run in wall speakers?


My friend has an older rotel 5 channel power amp that he used to use with a rotel home theater preamp for a home theater.  Now he has a modern marantz home theater receiver that handles the home theater.  His new house has 8 in wall speakers distributed throughout the house.  He has a sonance speaker distribution box.  I advised him to use the rotel power amp to drive the speakers in the sonance box, using the pre-outs from the Marantz.  The current set up can only make use of 2 channels, due to the 2 pre-outs from the marantz, and thus, 3 of the channels in the Rotel power amp are going unused.  I'd prefer to put one pair of in walls at least on its own channels in the rotel, and minimize the quantity of speakers in the sonance box.

any thoughts?
marktomaras

Showing 3 responses by dtc

If, in fact, one of the speakers is truly mono, then you might want to think about making everything mono.    Wall and ceiling speakers and outdoor speakers seldom benefit from being stereo and mono is often better since there is seldom a "sweet spot". You can do this with simple Y cables - not elegant and I would not do it for critical listening, but it is often a good option for whole house music.
That Marantz has Zone 2 output, as long as you are using 5.1, not 7.1. You can use Zone 2 pre-outs to feed the Rotel to drive the whole house speakers. You can connect all the speakers to the SS-6 and the Rotel will probably have enough power to drive them, although I would check to see if it can handle the 5 ohm load from the SS-6. In-wall and outdoor speakers are usually pretty efficient so the Rotel should be OK if it has 100W output. You will probably need analog inputs to use Zone 2.  Also, check to see if the speakers are all 8 ohm. That many 4 ohm speakers would definitely be a problem

You can certainly use a simple RCA splitter to separate the signal in order to use 4 channels of the Rotel. There can be some minor impedance issues between the Marantz and the Rotel doing that, but the effect is pretty low and should not be an issue for whole house speakers.

The biggest problem will be volume control. You are almost certainty going to want to be able to change volume for different rooms. You could use impedance balanced speaker selector boxes like the Niles SSVC-6. Make sure such a box has impedance matching. For example, the Monoprice ones do not, I believe.

So, I would check the speaker impedances, the impedance the Rotel will handle and think about volume control.
I was typing while you posted, but here is some additional input. Sounds like you have a solid direction in which to go.

My original post :

I agree that a resistive stereo to mono adapter is better than a y cable, although I find that in most situations the y cables are fine for this type of application. The one suggested should be fine.
And y cables can certainly be used to split out the signal into two signals.

I suggested using zone 2 because it can be independent of the main output. However, to use it you will need analog outs from the Apple TV, which I do not think it has. So, zone 2 is out if the source does not have analog outs.

So, that leaves the stereo pre-outs with volume controls(s) and Y cables and maybe a stereo mono converter. Several small parts, but it should work.

My guess is that the Rotel with handle a 4 ohm load (assuming that is what the SS-6 presents in Protect mode), but you need to check that first. Do you know the model?

If the Rotel handles 4 ohms, before going much further I would suggest hooking up the the Rotel to the 5006, and feeding that into the SS-6 with all the speakers connected. That will give you an idea of whether you have enough power to drive everything and whether you will need additional volume controls for different rooms and for outside.

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