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Amp switcher with tube amp protection

Hi there, I'm a bit of a beginner, so stick with me please :)

I'm looking into buying a tube amp (muzishare X7), but would prefer to also keep my solid state amp for movies and tv so I don't waste away the tubes on unimportant stuff :) Would prefer to use just 1 set of speakers as i got rid of my surround setup and settled for some Klipsch rp600m.
I'm looking for a amp switch that will protect the tube amp from not being hooked up to speakers. I know i can turn it off, then switch. But I'm sure I will one day make a mistake there.
I did stumble upon a thread here about somebody building his own switch. But are there commercial options out there? Because I couldn't find any.. or maybe I'm searching with the wrong search terms.. 
Also preferably not too expansive as my setup would be quite low end in terms of audiophile gear...

Hope someone can point me in the right direction!
BestMartijn
mw000
mw000 OP
4 posts
 
Thanks for your great explanation, makes sense to me even without much proper knowledge of electronics.

For me to build this would maybe be a bridge to far at the moment though. Although it sounds like a cool project, making a nice casing etc. I just don't have any tools to do this, plus would be afraid to mess it up and fry my amp 😅

I find it hard to believe there aren't any commercial solutions though. It doesn't seem like a crazy rare use case to me?
elliottbnewcombjr
5,376 posts
 
I used to run mono tubes; tube receiver; SS. I put 6’ runs from my speakers to female banana connector to receive male bananas. a hook on the wall behind so I didn’t have to bend too much.

each amp it’s own speaker wires with WBT tightening banana plugs which are OFC copper

http://www.wbtusa.com/pdf/0645.pdf

these are similar, but brass

https://www.amazon.com/Locking-Speaker-Connectors-Terminal-Connector/dp/B0811LF7BW/ref=sr_1_3?crid=1...

some nice pure copper wire

https://www.amazon.com/InstallGear-Gauge-Speaker-Wire-Oxygen-Free/dp/B079VJXN1Z/ref=pd_bxgy_2/137-61...

I make my own speaker wires from OFC Cat 8: 22ga x 8 = 13 awg.

a source popped up

https://alitools.io/en/showcase/hifi-audio-4pcs-mca-ofc-gold-plated-banana-lock-plugs-hifi-speaker-b...
mw000 OP
4 posts
 
So in other words, you don't use a switch but change your cables all the time.. ;)

Soooo, would be great to hear if there are switches out there that can do the trick :)
Post removed 
imhififan's avatar
imhififan
2,182 posts
 
The most simple way to protect your tube amplifier output transformer is connect a 5Watt 100Ω - 150Ω resistor across the "+" and "-" speaker output binding posts of your tube amp, either 4Ω or 8Ω tap is OK, it will provide some load to the tube amp when the speaker is disconnected. 

https://rukminim1.flixcart.com/image/416/416/kgfg2vk0/resistor/j/v/r/100-ohm-5w-wire-wound-resistors... 

There also a switcher with built in loading resistors:

https://www.amazon.com/Amplifier-Receiver-Speakers-Selector-Switcher/dp/B0796KGVXT
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