multiple amps and speaker selector

paysonmark

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Hello all , I have 3 tube amps (st70s) and 3 pairs of speaker. I want to add a switch box to choose and amp with any speaker pair. Ideas are welcome

I need a suggestion on how to protect the tube amp outputs so they always see a load with no speaker connected or during the switching period.

thanks
 
Hello all , I have 3 tube amps (st70s) and 3 pairs of speaker. I want to add a switch box to choose and amp with any speaker pair. Ideas are welcome

I need a suggestion on how to protect the tube amp outputs so they always see a load with no speaker connected or during the switching period.

thanks
Solder a resistor , 100ohm5w to the 16ohm outlet. This will absorb dangerous voltages that might occur during switching and no load conditions. Still, the unused amps should not have any signal.
 
Here's my 2 cents:

Terminate the speaker cables with banana plugs.

Wire the amplifiers' speaker connections to one of these:


With the amplifiers powered off, you simply plug whichever speakers you want into whichever amp you want.

Use something like a Niles AXP-1 to switch the RCA output (e.g., from CD player) between the amps.

This can serve many amps, and many speakers, and has no amp power limitations, and no concerns about frying an amp because of what's going in inside a box.

I have this installed in several systems. Works great.
 
My rudimentary system.
Dual banana sockets on home-made brackets.
I plan on adding 470 ohm resistors to the sockets so that the tube amp sees a load if I accidentally turn it on without speakers connected.
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That is a great idea. I too have to add the resistors. I only switch a tube and a Marantz and use this. It works well. But until I add the safety resistors I have to remember not to power up my Dynaco until switched.

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