about mics that have extended frequency range

Question

hello all,

excuse my noobiness again, but i was wondering, will i get more high frequency information when recording high sample rate audio using mic that has extended frequency range, and slowing it down? will i get similar results with mic that records up to 20khz?

maybe someone has some samples of the same sound recorded for example with 20khz mic and 35-40khz(or similar) mic in at least 96khz sample rate?

also whats the cheapest mic that has extended frequency range? (i saw some 1000$ mics, but that's out of my budget) :)

Answer 1

All pro mics will record something up above 20k, and some mics will record a heck of a lot up there. The only thing is that what gets recorded up there may not be linear, but when you're talking about pitch shifting and sound design that's less of an issue IMO. Also, only certain things really do a whole heck of a lot up above 40k. Most living things really can't generate frequencies up higher than that. Metallic and electronic things can though.

I have great success with the built in electrets on my PCM D50.

Here's a recording of a metal spinning gate captured with the D50 and slowed down to 20%. You'll notice that it still sounds pretty full res, even though I've slowed down enough to pull all of the ultrasonic info down well below 20k.

[soundcloud]rcoronado/revolving-metal-gate-20percent[/soundcloud]

All that said, extended frequency rated mics certainly can produce comparatively nicer results way up there.

Here's a test that Frank Bry did with a 416 (rated to 20kHz) and an 8040 (rated to 50kHz)

source and pix here

[soundcloud]therecordist/sets/chains-8040-mkh416-comparison[/soundcloud]

Answer 2

One of the things you're paying for with microphones is frequency response. If you want extended (and linear) response, you're going to have to pay for it.

You can also check out this thread for a bit more discussion on the subject. [Just updated the link in my post.]