Microphone splitter schematic required ...

for electronic DIY’ers

Hi there !

I’m looking for a schematic for a circuit (active or nonactive) that will enable me to plug a balanced mic into the one end, and then have two seperate (and isolated) outputs (also balanced) that I can send to two mixers.

I already have a schematic for unbalanced (and passive) that i’ll be using for guitar, but I’m still looking for a microphone one…

Thank you in advance !


P.S. Sorry for the duplicate post for both forum dwellers…

The “last word” in mic-splitting is using a Jensen mic splitter transformer. Totally passive (add connectors and a box and you’re done), and the Jensens are about the best mic transformer on the planet. The downside is that the suckers are $60 each. There are application notes and circuits on their site.

On the extreme cheap end, you could try a straight Y splitter cable connecting a mic to 2 inputs, but it’s likely that the total load on the mic may alter its sound. You can improve on this by splitting using resistore - eg use 470 ohm in at each input. This will work, but it cuts the mic level down a bit. Like so:

Mic out
2 -------------------o-----------470-----------2
| Mic Input 1
3 -------------------------o-----470-----------3
| |
| Mic Input 2

grounds not shown. ASCII schematics suck…copy/paste the above into a proper text editor if it looks bad. This circuit may affect phantom power to some mics.

When splitting the mic, sometimes you run into trouble when the mic ground (shield) is connected to both consoles. Better splitters have a switch to lift one of the console grounds when necessary. Also be careful which console supplies phantom

If one of your consoles can supply line-level direct outs from each channel, a good option is to connect the mics to that console, and then hook all its channel direct outs to the line-level inputs of the second console.

Thanks for the info !


This will work, but it cuts the mic level down a bit.
That should be fine, as a little attenuation is better than sound alteration.

Thanks for the info !