Can I "match" electret condenser mic capsules without using sound?

[tuprimo]

Basically, I want to match mic capsules (pair those with similar sensitivity) without using sound.

I know that to do this more accurately, I would need an anechoic chamber to measure an acoustic signal, but the capsules are very sensitive (-25dB ± 3dB) and I don’t have an anechoic chamber. Building one to the proper standard seems difficult.

What I’m interested in is not knowing the exact sensitivity, but simply trying to match them. Could I do this without sound?

According to ChatGPT, I could calculate the relative sensitivity, which would give me an approximation to match them. It would be done with a frequency generator, a power supply, and a multimeter. Is this correct, or is it a waste of time?

The capsule works at 1.0V-10V(DC) and has an internal PET, resistor, and capacitor, with max impedance 2.2KΩ at 1KHz, and current consumption Max.0.5mA.

That 1µF capacitor and 2.2kΩ resistor are according to the manufacturer's test.

I’m a complete beginner, so sorry if this doesn’t make sense XD.

thanks.

 

[staticV3]

What I’m interested in is not knowing the exact sensitivity, but simply trying to match them. Could I do this without sound?

No, but you don't need an anechoic chamber either.

All you need is a constant sound source and a way to mount the capsules repeatedly and consistently.

Then you can measure differences in sensitivity and frequency response, even in an echoic environment.

 

[Blumlein 88]

Expanding on what staticV3 is saying, put them a couple meters from a speaker. Play pink noise. Put up one capsule and measure the level. You can adjust the speaker output to get a reasonable output from the capsule. Swap in a second capsule in the same exact physical position as close as you can manage. Measure this one without changing the output level coming from the speaker. Rinse and repeat. REW is free software good for this. Be wary of HVAC or other appliances turning on and off. You might need to repeat as outdoor sources can corrupt the lower frequencies below 100 hz. It is very doable, I've done it with good repeatable results.