Using my headphones with my computer is frustrating. Whenever I want to use my headphones, I have to move my computer so I can access the back panel, unplug my computer speakers, and plug-in my headphones. Okay, maybe it isn’t that difficult, but it should be easier. How about a device that allows you to select between headphones or computer speakers?

Solution

After some careful thought, I realized such a device could be implemented using three 3.5mm jacks and one dual-pole dual-throw (DPDT) switch (see the schematic below).

audio output selector schematic

As you can see, the DPDT switch simply selects whether the input is connected to the headphones or the computer speakers.

Other Possibilities

A similar device can be implemented using two dual-pole single-throw (DPST) switches. This would allow the user to select headphones, computer speakers, or both. A much more sophisticated implementation might include operational amplifiers allowing the user to adjust the gain on each output.