Using a speaker switcher

[dazed&confused]

Is the use of an A-B speaker switcher likely to introduce any problems into my system, or affect sound quality? Also, does anyone know of a remote control one?

I was thinking of upgrading my AV amp by puchasing one second-hand, probably a Yamaha V2700, but need true A-B switching functionality - my A speakers for cinema/music face across the room toward the sitting area; perpendicular to this, my B speakers just for music face down the length of the room toward the dining area.

Switches seem to vary vastly in price, from just a few quid:

2-WAY Speaker Switch, Black: Amazon.co.uk: Electronics & Photo

Through £15 for something that clearly looks like important issues such as impedance matching have been considered:

2 Way Stereo Speakers Switch Box : Speaker Switchers : Maplin

To about £50 for something which looks fairly easy to operate, even once it is tucked away out of view, underneath my little 'hifi table' alongwith my Cyrus amp:

QED SS22 2 WAY SERIES SPEAKER SWITCH - available from Superfi UK Visit http://www.superfi.co.uk/index.cfm/page/moreinfo.cfm/product_id/1382 for details

QED SS21 2 WAY PARALLEL SPEAKER SWITCH - available from Superfi UK Visit http://www.superfi.co.uk/index.cfm/page/moreinfo.cfm/product_id/2043 for details


Does anyone know of any problems/performance degredation that using such switches could cause?
Of the last two I have shown in the links, one switch is parallel and one is series - what are the implications of using one rather than the other?


Many thanks .....


Universal disk player Yamaha DVD-S2700 into AV amp Yamaha DSP-AX750SE pre-out to stereo integrated amp Cyrus 6vs. Front A speakers Castle Compact Columns; Centre Castle Compact L-C-R; Rears Castle Compact satellites; B speakers (dining area) Castle Compact satellites; Subwoofer Castle Compact Cube. Plasma TV Panasonic TH-37PE50. Interconnects Mark Grant Cables throughout.

 

[dazed&confused]

bump.

 

[Mark.Yudkin]

A properly designed and manufactured speaker switch will have no audible effect when used to switch. When used to split (drive two sets of speakers simultaneously), there will likely be an audible effect. The QED models are probably properly designed and manufactured, I am not familiar with the other two you mention.

Series means the speaker connection is amp -> A -> B; this is uncommon. Parallel means amp -> A and amp -> B. For series, the total impedance is the sum (R1+R2), for parallel it is 1/(1/R1 + 1/R2)). More here.

Remote control speaker switches are manufactured by custom installation suppliers. Prices are a little higher that your implied budget. As an example: http://www.awe-europe.com/product_description.asp?idProduct=860 (two speakers, pure switch) or http://www.xantech.com/products/i_folder/i_68610.pdf (6 speakers, splitting supported). Sonance and Russound are other sources.

 

[dazed&confused]

Thanks for you reply, Mark.

I would only ever want to listen either to the A speakers or the B speakers, never to both pairs together. My A column speakers have a nominal impedence of 6 ohms; my B satellite speakers have a nominal impedance of 8 ohms.

As I understand it, if I bought the parallel switch then when listening to the one set of speakers, the circuit to the other set would be broken. Hence, the total impedence would be just the imredence of the set of speakers being used (plus any negligable imedence of the switch and cable).

I'm struggling to understand the series set up - how one would listen to the B speakers with the A speakers in the circuit but not actually playing. It seems to me that the circuit would act in series only if both sets of speakers were being used; with only one set being used the circuit would be no different to using the parallel switch. Is this right?

I wonder, under what circumstance one would want to use a series circuit with two sets of speakers? In my situation the impedance would be increased to 14 ohm, so there would be a drop in current and therfore a drop in power reaching the speakers.

 

[Mark.Yudkin]

A series switch would either pass the signal through the speakers or "short". Presumably there would be sme form of protection against shorting when both speakers were off. As I said, it's not common. Presumably you'd use it when driving low a pair of low impedance speakers (<= 4 Ohms), so as to prevent the impedance getting too low (2 Ohms in parallel).

 

[dazed&confused]

Thanks Mark.

I'll try contacting QED, to check that I should get the parallel switch.

 

[RichardK]

I have the SS21 QED switch and use it with two pairs of speakers. It will work for what you want to do, and doesn't affect sound quality, but having opened it up I wouldn't recommend you buy it.

It is just a couple of push switches connected to some posts for the speaker cable to connect to, and wouldn't do any more for sound quality than this much cheaper one from CPC.

--|A098J|SPEAKER SWITCH, 2WAY | CPC

 

[BlueWizard]

Don't want to be contrary hear, but doesn't your existing AV amp have a Speaker-A, Speaker-B, or Both switch built into it? Most of them do.

What is the brand and model of your amp? Ah...I see it in your signature.

From your Signature -

"...AV amp - Yamaha DSP-AX750SE pre-out to stereo integrated amp Cyrus 6vs. Front A speakers Castle Compact Columns; ...; B speakers (dining area) Castle Compact satellites;...'

Since you have merged a stereo and an AV amp, why not have the stereo drive the stereo speakers and have the AV amp drive the AV speakers?

If you are pre-amping to a stereo for the front speakers, then you have two spare channels on your AV amp that aren't being used. Why not use them?

Again, I suspect both the AV amp and the Stereo amp have a Speaker-A/Speaker-B switch built-in. A quick look at the owner's manual or just a look at the amps themselves, should tell you what you need to know.

EDITED:

A quick check of the internet indicates that the Yamaha amp does have a Speaker-A/Speaker-B switch. However the Cyrus 6vs, while it has four sets of speaker terminals, doesn't seem to have a switch to control them.

But once again, if you have one set of speakers for Stereo and another set of speakers for surround sound, why not connect the stereo speakers to the stereo amp and the surround speakers to the surround amp?

Just a thought.

Steve/bluewizard

 

[dazed&confused]

Hi Richard, thanks for the reply.

That seems a little crazy - I'd have at least expected a few components in the box for my money I guess one advatnage of the QED switch is that it would sit firm and be easy to use when it is tucked out of the way. Does it have much weight to it?

 

[dazed&confused]

Hi Steve.

Many thanks for writing, and taking the trouble to help me think through this.

A quick check of the internet indicates that the Yamaha amp does have a Speaker-A/Speaker-B switch. However the Cyrus 6vs, while it has four sets of speaker terminals, doesn't seem to have a switch to control them.

You're right - my amp has a speaker A/speaker B facility, so at the moment everything works fine. However, the issue I have is that I'm thinking of upgrading (to an Rx-V2700 or RX-V3800) and these newer Yahamha amps (even the Z7 and Z11) do not have a true A/B facility. They have zone 2 and 3 but this facility is quite useless, working only for analogue inputs and from different rempote etc. The four sets of speaker terminal on the Cyrus amp are for bi-wiring speakers, not A/B.


Since you have merged a stereo and an AV amp, why not have the stereo drive the stereo speakers and have the AV amp drive the AV speakers?

A couple of reasons. Firstly, the A speakers (Castle Columns) which face into the lounge area, peform both cinema and music duties. The idea of pre-outing from the AV amp to the Cyrus amp is to improve sound. Secondly, I neevr actually touch the Cyrus amp - it is sat hidden out of the way and, whether or not the Cyrus is in use, source and volume are always controlled by the AV amp. This does of course mean that the Cyrus only comes into play when the A speakers are being used - an incidental advantage of having to use an external A/B speaker switch when I upgrade is that the Cryrus coudl be in use for both A speakers and B speakers.

If you are pre-amping to a stereo for the front speakers, then you have two spare channels on your AV amp that aren't being used. Why not use them?

That's taken me by surprise - I've never thought of doing this, until you suggested it Would it work, though? In effect I'd have two loads on the amp - both pre-out (A speakers) and an output from the power stage in the AV amp (B speakers), both playing simultaneously. I could kill the sound from the A speakers by pressing the mute or standby switch on the Cyrus (which I need to do at the moment anyway, when using speakers connected to the B terminals). Would it harm the AV amp to be running output to two lots of speakers on A?

Many thanks,

 

[BlueWizard]

But the AV amp ISN'T running two loads. One load is on the Pre-amp section and that is virtually no load at all.

The other speakers would be on the standard AV amp front channels, and that is one-amp one-speaker, so no problem there.

It sounds like either speakers could be used for music depending where you are listening. For serious listening, the Stereo amp and speakers would get the job done. For less serious listening, simply using the AV amp fronts would do a good enough job.

And you are right, you can still select which speaker you want on, one or the other or both.

Just a thought.

Steve/bluewizard

 

[dazed&confused]

It sounds like either speakers could be used for music depending where you are listening. For serious listening, the Stereo amp and speakers would get the job done. For less serious listening, simply using the AV amp fronts would do a good enough job.

Hi Steve - yes, this is in effect the set up I already have. I pre-out to Cyrus for serious listening at the lounge end of the room, using speakers A. I use speaker B terminals on the AV amp (post power-amp stage) for the B speakers facing the dining area, for background music (The B satellite actually sound fine because they get the benefit of playing down the length of the room, having a wall at equal distance either side and the bext spatial relationship to the sub; since the A speakers play across the room at the lounge end, with the right speaker thus 'leaking' into the dining area space, and also being floor standers, they benefit from the helping hand of the Cyrus improving the width of the 'sound stage' and keeing the bass a little tighter).

Until your post it never occurred to me that using the pre-out left a spare pair of terminals that I could use for B speakers Cheers

 

[RichardK]

Hi Richard, thanks for the reply.

That seems a little crazy - I'd have at least expected a few components in the box for my money I guess one advatnage of the QED switch is that it would sit firm and be easy to use when it is tucked out of the way. Does it have much weight to it?

It looks like Steve has saved you from needing a separate switch, but I'll answer anyway.

The switch doesn't have much weight to it, but you don't need to use a lot of force on the buttons so that's not a problem.

 

[dazed&confused]

Thanks Richard. It's useful info for me to bear in mind, as I'd still need to piurchase a switcher if I wanted the possibility of using the Cyrus for both sets of speakers

 

[phil2009]

I have a "speaker A and B" button on my yammy, and Ive made use of it by rigging some speakers up in the bathroom

 

[dazed&confused]

I've just thought about this a little more and realised - if I am thinking straight - that Blue Wizard's suggested use of the 'spare' front speaker terminals on the AV amp wouldn't work. It would work fine when listening to the B speakers as I could mute/turn off the stereo amp connected to the front speakers, which is what I do at the moment. However, when listening through the A speakers, sound would come from the B speakers simultaneously - there would be no way to turn them off.

So I guess a speaker switcher would be required after all.

 

[panrixx]

On a similar topic, is there a switch which would allow a pair of speakers to be shared (one at a time) between two different amps?

The idea is to use the two speakers for either the cinema surround sound rears OR for the hi-fi tuner.

 

[dazed&confused]

Panrixx, I think that is a substantially more complex - and thus more expensive - engineering problem, but there are solutions available. Here is a link to one such solution that I came across when searching for a simple speaker switch for my own purpose.

CyberSelect | Russound automatic A/B speaker switch

 

[panrixx]

Panrixx, I think that is a substantially more complex - and thus more expensive - engineering problem, but there are solutions available. Here is a link to one such solution that I came across when searching for a simple speaker switch for my own purpose.

CyberSelect | Russound automatic A/B speaker switch

Thanks, that is just what I was looking for although at a higher price than I had hoped.

 

[Mark.Yudkin]

Other manufacturers include Sonance and Speakercraft, but pricing of home automation is always going to be at those "higher prices than you hoped".

A mechanical switch can be obtained for beer money, just make sure it's double-pole, double-throw, break-before-make.