Could a PC calabrate a cheap PC mic?

[Spinnor]

Say we have a cheap PC microphone attached to our computer. If our computer could produce a test sound that varied intensity and frequency with some degree of precision then our cheap microphone input signal could be calibrated in some sense? Once the mic was calibrated software could correct the recorded signal and make a cheap mic produce better recordings? This might also take into account the room acoustics?


Thanks for any help!

 

[vk6kro]

That could probably be done. There are a few problems, though.

One is that the generated signal would have to be reproduced by a speaker, and speakers have their own problems of not reproducing all frequencies equally.

If you had a known good quality microphone, you could plot the output level for a range of frequencies and then plot the same range for the cheap microphone. Peaks and nulls at the same frequency could be blamed on the speaker but those that didn't occur with both microphones could be blamed on the cheap microphone.

If there were no sharp peaks or nulls, you could probably use a graphic equaliser to compensate to some extent for the cheap microphone's poor low and high frequency response.

I don't know of any software that does this automatically, however there is a program called "Spectran" which gives a great spectral display and you could use it to compare microphones. I think this is a free program.

Perhaps it would be easier with two computers, though. One to generate the signal to drive the speaker and one to process the microphone output.

There are audio signal generator programs available too. Just try Google.