Looking for an A/B switch to switch between two stereo sources connected to one output. Prefer 12 volt activated, not signal sensing. Niles and Sonance used to have them. Niles does still have the RCA/Speaker level combo unit. I will use that if I cannot find the simpler, less expensive line level only unit.

Thanks

Niles AVS-2?

That's it.

Thank you!

I used to use the Sonance, but they discontinued it. I haven't tried the Niles; Hopefully it's better than the Sonance was. With the Sonance, it caused a loud "Pop" when you switched inputs. It would inevitably make the client jump each time it changed inputs. Definitely not ideal!

Since the discontinuation of the Sonance AL1-S, I've just been building them. For about $10.00, I can buy a 4PDT relay and a socket with screw terminals and mounting holes. I cut a couple of inexpensive audio patch-cables in half for the inputs and outputs, It seemed to work better than the $50.00 product that Sonance used to offer, but still had some degree of popping during the switching of inputs.

For more critical applications, I use a triple-relay circuit. A small SPDT relay, activated by the trigger voltage, determines which of two 4PDT relays are engaged, each of which enables one of the inputs to be switched to the output jacks. The release of each of the relays is delayed by a small electrolytic capacitor. For a short amount of time (approximately a half a second), both relays are engaged simultaneously, but the output is shunted to ground with 47-ohm resistors during the transition. After the trigger-voltage changes, one relay lets go (after a half a second), while the other stays engaged. It works well, but takes a little more time to build. I can build it for $25.00 to $30 in parts, plus a half an hour of my time. There are, of course, ICs that can do the switching, but they are more tedious to build and not as much fun. Sometimes I find it fun to go back to my roots and build something, as I did when I was a young(er) nerd.

If I don't have the time to build something like this, I can always fork out the cash for a fully-electronic relay built by Radio Design Labs. The RDL relay works well, but it's not cheap.

Usually a pop occurs when a source has some DC on it that does not show up after the source has been connected to an input, but accumulates (in milliseconds) on the output when the output is left open. Connecting to an input, that DC makes the pop. For this reason just a relay doesn't cut it with switches like this -- there should be some high resistance to ground to bleed off possible DC on an output.


Proving my point.


Don't let bcf1963 see this. He will swear this won't work reliably and the delay must be accomplished with a 555 or other timer circuit. Between us, well, we know it works.


Shunting any possible DC to ground. I'm appreciating how your description follows my original point.


My point repeatedly with bcf1963.
I think we're about to see if he has google alerts.


I rarely build anything like this any more because I want it in a chassis with connectors -- sounds like yours is done with flying leads -- which means putting things on a PC Board or otherwise mounting the parts, working out either an internal power supply or getting a wall wart with a matching power connector for the chassis... the chassis work is 3/4 of the time it takes to make something like this. Or maybe 7/8.