WM-60A frequency response

A while ago I found a description of measuring microphone on Linkwitz site. Remembering his name from 20 year old publications, related to speaker design and evaluation of crossover networks, I was really intrigued by the fact that reasonably good measuring microphone could be done from $2 electret capsule. Next day I ordered a couple of WM-60A Panasonic capsules from Digi-Key. A few days later I build a microphone form arrived capsule. I used his modification, converting common source integrated amplifier into common drain follower. Then I buffered it by simple emitter follower and powered from 9V battery.

I send it to Laboratory of Electroacoustic of NIKFI, Moscow, and my friends measured frequency response of this homemade miracle in acoustic anechoic chamber. I don’t remember what kind of B&K measuring microphone was used to create calibrated field, but this was the same setup that they were using to measure frequency response of professional studio condenser microphones.

WM-60A frequency response

WM-60A frequency response

 

Don’t pay attention to small bump at 2 KHz, it is related to loudspeaker problem.

The second plot is just repeat of 0 deg measurement to double check.

My overall impression-not bad, not bad at all for $2 capsule.

Comments

One Response to WM-60A frequency response

  1. zega says:

    I am anxious to see a photo of their measurement setup…
    A lot of guys have similar kind of a ripple in the high freq. region.
    I nailed that with my measurement setup, it is microphone placement compared to the stand, and microphone tube length, basically mechanical design&placement…
    Early reflections from these obstructions (no matter how small the surface).
    I used WM 60A also and compared it with some cheap beyerdynamic measurement mic, WM60a was better (and thinner design also)…
    I give that mic to the guys @ Zagreb ETF electoacoustic lab and i got back is 3 point measurement (useless) i was pissed @ their incompetence or laziness…