Making a simple Mic schematic negative ground instead of positive?

[Chris S]

Hey all i've used this schematic for a microphone inside a resonator (blended with a piezo) is there a way I can rewire it so it is negative ground?
Thanks!

[willienillie]

Is the mic a condensor that requires +/- 9v?

[Chris S]

Yes. I'm using a panasonic WM-61a electret condenser capsule.

[willienillie]

I'm not familiar with it, and I'm no expert on microphones (or anything else really), but the first Google result was this DigiKey listing:

https://www.digikey.com/product-detail/en/panasonic-electronic-components/WM-61A/P9925-ND/252843

The second image shows an example circuit with unipolar power, negative ground.  With only two solder pads, I'm not sure how you wired it with bipolar power.

I could be missing something.

[Chris S]

The above is not bi polar just positive to ground. Looking at the data sheet schematic looks like I could just swap the two mic connections (labeled 2&3 on the drawing) then swap the + and - battery cables.

[willienillie]

Okay, I admit I can't follow your drawing too well, but you have labels for +9v and -9v, so I thought bipolar.  I guess you mean -9v and 0v?  Why did you wire it positive ground to begin with?  I don't mean that in a condescending tone, I'm genuinely curious and confused.

[Chris S]

Your right about the drawing (which isn't mine) the +9v is attached to the sleeve of the output jack so it should be labeled just as earth.

[tubegeek]

Have you found real Panasonic WM61A's? Or are you using one of the many generics?

[Chris S]

I believe they're real. I bought a 10pack about 20 years ago.

[PRR]

I don't think the drawing in the top post is even right.

I've always powered electret capsules negative-ground. They were common in answering machines which were usually negative ground. I'm not sure why it would be done any other way.