Hi guys I need to pick your brains please. I have two amplifiers that I want to choose between when plugged into the 3mm socket on the motherboard of my PC. One amp is hi fi, the other a cheapo computer amp. Both amps are fed from a male 3mm plug. Both amps have their own speakers. Obviously I can pull one system out and stick the other in but this means rummaging about underneath my desk. Do you know of a switch / circuit that I could use for this that I could have on my desktop to enable me to select what amp I wanted. Thanks for any help.

 

You may buy the switches as this and with lock and using cable to connecting.

 

Hi ScottWang, I have never seen one of these before. Any suggestions on how I would wire this please. Thanks

 

Attach your plugs of two amps.
Maybe you need to build a box to put that two plugs and the earphone jack for stereo and the push switch.

 

You need to build a box similar like this, but yours is more easy and less wiring.

 

Get a two or three position switch.

If you get two position, then you simply toggle the switch to select the amp you want.

If you get three position, then you can get: left-select amp 1, center off (neither amp is selected), right-select amp 2.

Here is example of three position switch, MSP-3 in the table on the left:
http://www.digikey.com/product-detail/en/200MSP3T1B1M2QE/200MSP3T1B1M2QE-ND/3777908

 

A SPST switch is great if you have two mono signals with a common ground reference: you can tell if it only has a 3-wire cable. The common ground is the third wire.

If you have stereo you need a DPDT switch.

@ScottWang: I've seen those switches in products where multiple switches gang together, pressing one releases the others via a mechanical strip between them. Ever seen that strip for sale anywhere?

And if there is no common ground (separate + and - to each speaker) you could use a 4PDT switch. While probably 2x the cost of a DPDT it has it's uses.

 

@ScottWang: I've seen those switches in products where multiple switches gang together, pressing one releases the others via a mechanical strip between them. Ever seen that strip for sale anywhere?

Whatever only One Push Button Switch or multiple switches gang together, we can easily to buy them from our local EE store in Taiwan, there is nothing special about that kinds of switches, that kinds of switches will also selling in the Audio store for the audio products.

 

Thanks to you guys. There's a lot of info here and I intend reading it all. Robert