maybe you all can help

[FISH_MAN]

ok heres the deal. I have two amps that I need to switch between that are hooked to my spires one is my rotel "for movies" one is my mc275 "for music"
there are two separate runs of wire going to my speakers and I do not want to unhook them and change connections every time I want to switch what amp drives my speakers.is their a device that can do this? I really do not want to build it myself I already did some google searches but have not really found what I am looking for and figured you guys would be in the know.

thanks

 

[Bernard]

I think Wireworld makes some sort of "comparator" device that you could well use, but do you really want to introduce into your system all those extra contacts and additional lengths of wire? Easier to use banana plugs and do a manual switch.

 

[Rich]

This is a perennial problem for two-channel lovers that also want to use their main system for multichannel. How do you maintain a purist two-channel system while also having connectivity for multichannel. I researched the speaker switch issue at one point and couldn't find anything satisfactory.

What most people do, and what I did, is get a high quality two-channel preamp that has home theater pass-through and use your two-channel amp to drive your main speakers and a multi-channel amp to drive the center and surrounds. The only problem with this for your setup is that it puts a lot of "home theater" hours on your tube amp. I imagine that is what you are trying to avoid. The simple answer, which you probably don't want to hear, is that there isn't really any good way to avoid that.

There aren't any "audiophile quality" speaker switches out there that I am aware of, and introducing a low quality switch in that very important circuit will certainly degrade the sound. But then, changing out the wires every time you want to watch a movie isn't reasonable either. Good luck with it.

 

[Brad225]

Hey Fish, I have also had the same situation for a few years. I finally built a switching device. It was convient but didn't like the sound. So I went back to just changing cabling when needed. It's a pain but one less item in the 2 channel signal path.

 

[FISH_MAN]

what did you build that you did not like?

 

[amey01]

Rich has got the right idea, but you don't even need a preamp with pass through - you can just configure your processor to drive any preamp at a given volume setting - eg. half way.

That said, you'll still be using your valve hours on theatre time, but it's got to be better than adding switches and extra connections to the (high level) signal path.

Another option (probably the one I'd take) is to just buy another pair of crappy speakers and leave them connected to the Rotel all the time. Effectively two separate systems. That way you leave your 2-channel system uncompromised and unpolluted.

 

[Brad225]

I will dig it out and take a pic to post. I just felt it clouded the sound a bit. Too many connections.

 

[FISH_MAN]

I will dig it out and take a pic to post. I just felt it clouded the sound a bit. Too many connections.

I would appreciate that I am fairy good with electronics and I think I could build something solid that should work good if I do I will also place pics. I think I am going to use some heavy duty 30amp relays with low voltage DC power.this can't be any worse than using those cheap jumper clips Logan gives you for the binding post lol

 

[FISH_MAN]

obviously everything will be built into a nice aluminum box and have heavy binding post on the back marked for the amps and speaker connections with a switch on the front

 

[risabet]

ok here's the deal. I have two amps that I need to switch between that are hooked to my spires one is my rotel "for movies" one is my mc275 "for music"
there are two separate runs of wire going to my speakers and I do not want to unhook them and change connections every time I want to switch what amp drives my speakers.is their a device that can do this? I really do not want to build it myself I already did some google searches but have not really found what I am looking for and figured you guys would be in the know.

thanks

The easy cure is to just use the Mc and not worry about switching the amps. I too have a SS amp but the tubes are better for audio and for video and I use the tubes unless I switch the amps for some other reason. I don't worry about the life of the tubes, they're gonna wear out anyway.

 

[Beakman]

http://www.filnor.com/tech/literature/knifeswitches/Knife-Switch-Catalog-Full.pdf

 

[JonFo]

FishMan,

You might already be all over this, but for the benefit of others:

Electrically, what I believe you are looking to do can be summed up as a Double-Pole Double-Throw (DPDT) switch with break before make characteristics.


The later part is key, you really want to ensure your two amps are never ‘connected’ via the switch as it transitions from one input to another.

Your speakers would be connected to the common output of the switch, and each amp connected to their respective A or B inputs.

A relay controlled DPST with enough amperage (30amps @ 28VDC) and break before make characteristics like this one (which might be the one in your pic) would do:
http://www.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=Z269-ND

At $37 for the relay, plus a 12v power supply (any old wall wart that does 2W at 12v should be fine) a SPDT switch to toggle the 12v in to go to amp B, plus a little box to put it all in, and you’re done.

Less than $50 to make, supper simple.

Skip the terminals on the box and hardwire into the relay for even less of a concern over additional plugs, terminals, connectors, etc.

It’s for your personal use, not a commercial product, so just do it

And for the purists in the crowd, you have no idea what some vendors put inside their amps, small gauge wire, relays (yes, many amps have output relays, nowhere near as beefy as the one I linked), so a relay of this quality in the line is probably not going to be audible.

Anyway, for $50 and a few hours time, hard to go wrong.

 

[FISH_MAN]

FishMan,

You might already be all over this, but for the benefit of others:

Electrically, what I believe you are looking to do can be summed up as a Double-Pole Double-Throw (DPDT) switch with break before make characteristics.


The later part is key, you really want to ensure your two amps are never ‘connected’ via the switch as it transitions from one input to another.

Your speakers would be connected to the common output of the switch, and each amp connected to their respective A or B inputs.

A relay controlled DPST with enough amperage (30amps @ 28VDC) and break before make characteristics like this one (which might be the one in your pic) would do:
http://www.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=Z269-ND

At $37 for the relay, plus a 12v power supply (any old wall wart that does 2W at 12v should be fine) a SPDT switch to toggle the 12v in to go to amp B, plus a little box to put it all in, and you’re done.

Less than $50 to make, supper simple.

Skip the terminals on the box and hardwire into the relay for even less of a concern over additional plugs, terminals, connectors, etc.

It’s for your personal use, not a commercial product, so just do it

And for the purists in the crowd, you have no idea what some vendors put inside their amps, small gauge wire, relays (yes, many amps have output relays, nowhere near as beefy as the one I linked), so a relay of this quality in the line is probably not going to be audible.

Anyway, for $50 and a few hours time, hard to go wrong.

that is the site it is from yeah its a make before break the speakers would essentially be hooked to the moving contacts that go from one amp set to another

 

[JonFo]

that is the site it is from yeah its a make before break the speakers would essentially be hooked to the moving contacts that go from one amp set to another

Just to be perfectly clear: it's break before make that you want, right?

A make before break puts A and B in contact *during* the transition.

The one I linked to (and in your pic) are break before make (which is what you want).


I figure you know this, but again, clarifying for the others who might not be as up on electronics.

 

[Brad225]

I'm still looking for the switching box.

 

[Brad225]

Still looking now it is a mission. I can't find some unused equipment either. I smell something fishy going on here.
No offense intended. I will keep looking.