Multi-purpose system - question re: switching between surround and 2.1

[andreasmaaan]

I'm designing an on-wall speaker system, and I'm having trouble working out how to accommodate an unusual (but interesting) request. Thought there might be some good ideas here.

Basically, it's the living room of a couple's apartment, and the sound system needs to perform two functions:

1. 5.1 surround system for movies and TV
2. Stereo 2.1 system for a DJ setup

The layout is like this:

I've marked the speaker locations with lilac starts, and the subwoofer locations with green stars. The speakers will be about 1.2 off the floor, and the subs on the floor. The screen will take up the entire wall space above the DJ setup and speakers. These locations are essentially non-negotiable.

The main difficulty here is that the speakers that would be the L and C speakers in the surround setup will have to become the L and R speakers in the 2.1 setup (all three speakers will be identical).

So my main question is: Are there surround processors/receivers etc that are capable of re-assigning the C channel as an R channel when switching from 5.1 to 2.1 (obviously without making any physical re-connections)?

If not, can anyone think of another solution?

Many thanks

 

[m_g_s_g]

You are not going to like my quick and dirty solutions , but here I go:

a) One speaker selector (f.i.: I used to use a Monoprice 2 channel A/B speaker selector for the backyard deck) with R as input and C and R as B and A outputs. The C speaker would have to input cables: from the AV C and from the speaker selector B. Just make sure that the users always select B AND 2.1 at the same time (or A AND 5.1).
B) If I’m not mistaken, in my PC with Realtek audio chipset, you can reassign the analog outputs to whatever channel you prefer. I seem to remember that you could even do that changing some registry values. Maybe a PC based HT?

 

[JEarle]

Does the AVR have a multichannel input? If so, maybe plug DJ rig into L and C input?

 

[m_g_s_g]

@JEarle's solution looks clean to me if feasible.

About my option A, if the AVR has multiple zone support, you can of course skip the external speaker selector. Cable Zone 1 as usual and the DJ rig to Zone 2 L and C and NEVER use Zones A and B at the same time.

 

[andreasmaaan]

Thanks for all the suggestions @m_g_s_g and @JEarle

This is not my setup, so it has to be a simple, foolproof solution. These ideas are definitely helping, although I'm not sure any of them is quite feasible as it stands, mostly because they all involve some risk of damaging things if the correct settings aren't engaged.

The HTPC seems like possibly the best option so far.

I've never actually used an HTPC. Would I be able to preconfigure the presets using software so that they could then flick between them with a remote?

And would the HTPC output typically be HDMI, SPDIF, RCA, or something else? Or are there many different options?

FWIW, the best idea I'd previously come up with, which was to use a 10-in/10-out DSP with selectable presets, something like this. Though this would involve a lot of boxes and extra AD/DA conversions, and would not be cheap...

 

[dougi]

Can you not just use an AVR with external 5 channel pre in? Use L and R from the deck into left and centre ext in and a contrived subwoofer (L+R?) from the deck into the sub external in if sub use is required. Just change the surround mode to ext in for that situation using one of the AVR presets.

 

[dougi]

Does the AVR have a multichannel input? If so, maybe plug DJ rig into L and C input?

Sorry @JEarle I didn't see your same idea.

 

[Chromatischism]

I think Zone 2 of an AVR would be simple enough to setup and operate, assuming they don't plan on using both at the same time (you can but there are limitations).

Note that room correction typically only applies to Zone 1, but you can get around that by switching speaker wires as needed, then running the setup and saving that as its own preset. That is a one-time thing. In operation it would be: hit Zone 2 on the remote and also switch room correction profiles via the smartphone app.

If this is too much for them, you could forgo RC on the DJ system, stick with 1 profile for Zone 1, and if you turn corrections off for Zone 2, it should remember that.

 

[andreasmaaan]

Can you not just use an AVR with external 5 channel pre in? Use L and R from the deck into left and centre ext in and a contrived subwoofer (L+R?) from the deck into the sub external in if sub use is required. Just change the surround mode to ext in for that situation using one of the AVR presets.

Thanks @dougi. The reason I had ruled out this option was that (I assumed) the ext. in would bypass crossover and room correction settings. Will have to read up further on this.

 

[Chromatischism]

Can you not just use an AVR with external 5 channel pre in? Use L and R from the deck into left and centre ext in and a contrived subwoofer (L+R?) from the deck into the sub external in if sub use is required. Just change the surround mode to ext in for that situation using one of the AVR presets.

I might be missing something, but how would you tell the AVR to accept a center in, but output to the right speaker?

 

[andreasmaaan]

I think Zone 2 of an AVR would be simple enough to setup and operate, assuming they don't plan on using both at the same time (you can but there are limitations).

Note that room correction typically only applies to Zone 1, but you can get around that by switching speaker wires as needed, then running the setup and saving that as its own preset. That is a one-time thing. In operation it would be: hit Zone 2 on the remote and also switch room correction profiles via the smartphone app.

If this is too much for them, you could forgo RC on the DJ system, stick with 1 profile for Zone 1, and if you turn corrections off for Zone 2, it should remember that.

Thank for this also. There will already be a Zone 2 elsewhere in the apartment. I presume there are AV receivers with 3+ zones, though.

 

[andreasmaaan]

I might be missing something, but how would you tell the AVR to accept a center in, but output to the right speaker?

It would be outputting to the centre speaker (which would be the "right" speaker for the DJ setup).

 

[Chromatischism]

So you would not use Stereo mode, but something like Multi Channel Stereo? I wonder if that would sound right. Otherwise I'm not sure there is a way to play stereo content unless the AVR thinks it really is a R speaker connected to a R speaker out.

Could set them as Speakers B but that would require going into the setup menu to change each time.

 

[andreasmaaan]

So you would not use Stereo mode, but something like Multi Channel Stereo? I wonder if that would sound right. Otherwise I'm not sure there is a way to play stereo content unless the AVR thinks it really is a R speaker connected to a R speaker out.

Ah, yeh that would make sense actually :-/

It's a surprisingly complex problem, lol.

 

[Chromatischism]

Yeah. Come to think of it Speakers B and Zone 2 wouldn't work either unless they physically swapped cables every time. Hmm...maybe the speaker selector.

 

[dougi]

Thanks @dougi. The reason I had ruled out this option was that (I assumed) the ext. in would bypass crossover and room correction settings. Will have to read up further on this.

Yes you are right. External in assumes the DVD player or whatever is handling bass management. You would have to complicate it by adding a DSP or similar device (miniDSP should be simple enough?)

 

[andreasmaaan]

The best I can come up with based on all the advice (and avoiding overly fiddly/dangerous options from the POV of the end user) is:

I'd set up room correction manually at the beginning, and the presets would be stored on the MiniDSP, which is what you'd use to switch between HT and DJ presets, to control volume, etc.

The advantage of this system I guess would be that room correction settings could be optimised for each application. Another advantage could be that an additional preset could be set up for playing vinyl through the mixer but not only for the benefit of the DJ.

Still, this seems like a pretty expensive solution, involving one more AD/DA conversion than it should.

At least I'd be able to do optimised room correction settings for each application, and all presets would be stored on the miniDSP, so the AV pre would essentially just be there to decode from HDMI.

OTOH, it still seems unnecessarily complicated somehow...

 

[dougi]

I still think putting a miniDSP 2x4HD between mixer and AVR pre-in, to do bass management would be easier. Bluray via HDMI, mixer via analog pre-ins from miniDSP and use AVR presets to switch between the two inputs as required.

Yes the AVR would need to do the DRC, at least for the HDMI source.

 

[andreasmaaan]

I still think putting a miniDSP 2x4HD between mixer and AVR pre-in, to do bass management would be easier. Bluray via HDMI, mixer via analog pre-ins from miniDSP and use AVR presets to switch between the two inputs as required.

Ok yeh, this sounds like it would work too. Thanks

And it would avoid the need for an additional power amp (or an AV receiver with both pre-in and pre-out).

 

[dougi]

Ok yeh, this sounds like it would work too. Thanks

And it would avoid the need for an additional power amp (or an AV receiver with both pre-in and pre-out).

But to correct re DRC, in my AVR at least all DSP is disabled when using external in so the miniDSP would be needed to DRC the mixer source. At least you can optimise for that then.