How do I inexpensively (and accurately) test a microphone's frequency response?

1_21_gigawatts

Estimable
Jul 12, 2014
2
0
4,510
Calling all engineers, physicists and other experts:

I want to model the frequency response curves of large diaphragm condenser mics. I don't have an anechoic chamber, so I figured the next best thing would be induce the capsule with a high voltage electrode, cut the voltage to zero (instantaneously) and measure the microphone response through a software package. I got this idea from the following thread:

http://www.tomshardware.com/forum/43117-6-simplest-measure-mics-frequency-response


Aside from not knowing what the "right" induction voltage would be, I don't know if or how I can instantaneously cut the voltage. I've been looking at the following instructable for a variable high voltage generator. It mentions how it is "de-energized" but doesn't say if this is instantaneous or not.

http://www.instructables.com/id/Build-a-Variable-High-Voltage-Power-Supply/


There also is a cheap programmable DC power supply I found online...but the voltage seems much too low, and the amps much too high (30V/5A). Again, this comes down to what voltage I need for proper induction (without arcing), but the earlier methods are working with thousands of volts. So, please tell me, what voltage do I need for proper induction?

http://www.joyfay.com/digital-adjustable-single-channel-programmable-dc-power-supply-30v-5a-pps3005s.html?gclid=CKTu3oOrwL8CFWrl7AodHHoASA


The last idea I've seen is to build a crude Marx generator that builds up voltage and discharges across a gap. I suppose I could work with this, except I'm not sure if the acoustic quality (it's very audible) of it would interfere with the pure induction response. This seems very un-kosher, but I'm including it anyway. Here is an example of a very crude generator.

http://www.instructables.com/id/Build-a-simple-Marx-Generator/


Please respond with any input or questions you have. I am doing this for personal research and need the results to be as accurate as possible. Thank you for your time.
 

1_21_gigawatts

Estimable
Jul 12, 2014
2
0
4,510
You didn't read my post. If you did, you would have seen how much research I have already done. Please read a post before responding to it.

The link you provided is a bunch of guys (attempting to) measure a room with microphones. I am testing microphones in as controlled a manner as possible with respect to my small budget. What I am doing is akin to a scientific experiment. The results I produce need to be accurate and reproducible.

Has anyone read at least part of my post and have something helpful they'd like to say? I really respect the knowledge of professional scientists and engineers, and would really like some help from one (or more).