A-B switch

Any considerations that I need to take into consideration before building a simple A-B switch using a DPDT switch and some rca connectors? I know that without a volume knob, I can’t match volumes, but I don’t want to introduce any extra variables.

Thanks SBAF. You are all the absolute best.

 

I made one for comparing DACs. It’s not complicated. I used 3-pin XLR sockets for the input and two outputs and two 4-gang volume pots for level matching. The channels have separate switches because the number of wires to switch is otherwise unreasonable. I considered adding voltage meters to avoid having to match with a multimeter, but couldn’t find any parts that would have been easy enough to use (and there needed to be 8).

 

If you will use relays as switches, I recommend using relays from quasi-electronic telephone exchanges.



Such relays have very low contact noise

 

Here's a cheap off-the-shelf electro-mechanical switcher. I have a similar one I bought to compare DACs that's 2-in 2-out, but I don't see that one now. But 2-in 1-out is sufficient. Little Bear also sells on eBay. Seems to work just fine, volume knob for the output.

 

https://www.amazon.com/dp/B096KLDMCV/ref=emc_b_5_t

 

No way to level-match built into either linked switch, as far as I can tell.