[steinchen]

I want to make objective AB tests with different amps and configurations and wondered about the requirements for the equipment to switch amps

The source shouldn't have any problems driving 2 or 3 amps in parallel, with 50k pots on the inputs of the amps the source should be able to drive them without sound degration, so no switch or buffer is needed there, just a simple RCA splitter.

But what about switching the headphones from one amp to another ? Can I simply use a rotary switch (break before make I assume) to switch between the amps ? Is there a danger of frying the output stage when switching under load ? What do I have to do to minimize / avoid clicks and pops while switching ?

 

[morsel]

Switchbox Design Questions: morsel's A-B switch box

 

[__redruM]

Get a 3pdt switch from mouser, and make one up. Even more usefull, the same switch can be used to bypass and enable an amp, so that you can hear what the amp is adding.

I have one switch like this, and was shocked at how little the differences really are.

 

[Garbz]

Switching is much safer then unplugging your headphones IMHO. That should be fine.

Although beware A/B testing of amps normally doesn't show much of a difference in sound. I'd play a track let it sink in a bit, and play the same track through a different amp rather then A/B switching.

But each to his own.