Axiom Home Page Forums General Discussion Stereo One pair of speakers, two amps..?

Hey everyone. I just recently got a tube amp to use with my M22 speakers. I also have a kenwood solid state 5.1 amp that I was using before. Is there any way that I can hook up my pair of speakers to both my tube amp and stereo amp, for use at different times? When I'm listening to music I'd like to use the tube, and for watching DVDs and Movies I'd use the kendwood instead.

Thanks for any advice!

I'm thinking your going to have to use some kind of speaker selector to switch sources, but I'm not sure if they will work with a tube amp.

Holy schmolies. It's been what --- (checks posting history) -- almost two and a half years and you think you could slide right in with an innocent question and avoid any fanfare? Welcome back.

Now that that's out of the way, you'll definitely need a speaker switch. Any A/B switch of the "break before make" variety will do just fine. You'll connect the speakers to the common terminal (the one that usually goes to the amp), and connect the two amps to the A and B terminals.

Here are some options:

http://www.futurehomesystems.com/a500.shtml
http://www.crutchfield.com/cgi-bin/ProdView.asp?i=190SSVC2

Hi pmbuko, thanks for your reply!

Haha yeah I havn't posted in awhile, I didn't realize it's been over 2 years :P

Anyways thanks for the info, I looked around at some A/B switches on the internet. Most sites which sell them don't seem like they'll ship to Canada though. I did find one in Futureshop (is it american? they are owned by bestbuy), which is handy cause I can just go and pick it up.

I'm not sure exactly what you mean by 'break before make'. Does this one seem like it'll work? Quest QLS 6.1

Thanks again, it's a big help.

umm...I do not think you can connect a Tube amp to a switch box...I think. Some other tube amplifier designs will oscillate or go into overload if they are used without a speaker or resistive load attached to the speaker output terminals.

I learned the hard way.
Saturn

You could always wait until you've switched the box to power up the tube amp. Then again, I suppose many people don't power down the tubes so you don't need to wait for them to warm up.

I only have the tube amp on when Im going to listen to music.. I dont leave it on usually.

That reminds me, since this is my first tube amp, kind of an impulse buy without much research, is there anything I should know about using them? Any thing I should do to prolong the life of the tubes, etc.
Tube amp I have


So, if I switch the box before turning on the amp, it should work without any difficulty you think?

I was thinking that he would be switching back and forth to do a A-B hearing tests. Some tube amps are okey if they are not connected but I thought majority need them to be connected or they ossilate. Cary tube amps supposedly can be turned on not connected without ossilating.
Actually if they powered down and then powered up when the tubes were warm to begin with really doesn't deter on the sound that much specially if they have only a few tubes.

What would happen if I hook up two pairs or speaker wires to my speakers, going out to the two seperate amplifiers? Would it damage something? Even if only one amplifier was turned on at a time?

In reply to:

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Would it damage something? Even if only one amplifier was turned on at a time?

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As a non-engineer scribe, I'm going to cautiously say "yes".

I think that's a real bad idea. My understanding is that Peter's scenario is the only safe way to do this, while also keeping in mind that you would want to make sure you did things in the right "order" to avoid Saturn's unfortunate experience.

Paul, another welcome back, and yes,it would cause damage even if only one amp was on. While it may not be immediately apparent, what you propose is a "Y" type of arrangement with the operating amplifier feeding the speaker on one branch of the Y and the other branch feeding the inactive amplifier(regardless of whether it's switched on), as if you were driving it in parallel with the speaker. The power from the operating amp doesn't know that you don't want it to go into the other amp; it just follows the wires.

If both amps were on would that pose a problem?

Let me try to diagram what you were saying

[Tube Amp] -> [Other Amp] -> [Axioms]

no comment.

Thanks for making me feel stupid
I'm kind of confused as to what JohnK was suggesting. >-<

John was just describing the setup chrono envisioned, which would be like this:

[receiver]===[Axioms]===[tube amp]

An inactive amplifier, powered off or not, will present a complex load to the active amplifier if it is in the signal path, regardless of where in the chain it is located.

Dan, as the "Y" characterization indicates, the power can't just go into the speaker; it follows the speaker wire into the other amplifier. A switch box or similar device is needed to keep the amplifiers completely separated.

Yea, that is what I was thinking initially, for some odd reason the way John described it made me think the other way around.


We're talking having both the red and black wires match up from both amps...right?

Sure, it's a parallel(not series)connection. The power comes down the red wire from the active amp and right up the red wire into the other amp, besides going into the speaker.

Ahh okay, so that's a bad idea. Thanks for the info guys, you saved my equipment, ahaha.

Hmm I guess the Russound AB-2.2 sounds like a good solution then.

Saturn, Johnk and Peter all note good points here.
There is something in the routing about some switch boxes that you have to note and be careful in what is being switched when/where in the signal path. The Russound unit i have is dependant on the load of speakers attached and it has a manual with a graph of the proper setting prior to hooking up equipment.

I would consider asking an electronics pro friend before using my switcher with tube amps.

Hm I see, I sent an email to tech support at Russound asking if it would be safe to hook up a tube amp to the AB-2.2.

Hopefully they'll have an answer.

Ok so someone at Russound emailed me back. He said that it depends on the tube amp, whether it will be fine to hook up to the AB-2.2 switch box. Now, it's a difficult situation because my tube amp is some independant chinese made amp, I am not sure who built it, and so I have no one to contact about it.

Let's say I buy the switch, hook up both my solid state and tube amp to it. What is the worst thing that can happen? Could my tube amp break? What does it mean to "oscillate or go into overload"?

Sorry for all the questions, I just want to be cautious before buying something that may not work, or even harm my equipment.

The outcome of not connecting my amp to the speaker....had to raplace the fuse of one of the power amps. Has to change one of the tubes. There was a acrid burning smell but I do not know if it came from the one tube or the fuse shorting.

Do you like listen M22 with tube amp.