Chirp!

[audioguru]

Cheap electret mics have a very flat frequency response.
Here is one:

 

[ronv]

As a matter of fact that is the one I was looking at. I only wish it had better noise figures, but I guess 62 dB is pretty good for a microphone.

 

[kubeek]

Cheap electret mics have a very flat frequency response.
Here is one:

That looks a little suspicious.

 

[audioguru]

That looks a little suspicious.

It is true. Most inexpensive electret mics have a good frequency response.

 

[Mr RB]

Thanks for that AudioGuru, I had no idea.

The last mic I was looking at a chart was probably a magnetic diaphram one, as it was pretty bad.

 

[audioguru]

A fairly expensive Shure vocals dynamic (coil and magnet) microphone messes up its frequency response with a peak at mid-high frequencies.
They claim it makes vocals have "presence" (sound closer).

I think today it makes a shriek sound. You know how some singers sound like they have a whistle stuck down their throat?
Maybe it was designed a long time ago to help an AM radio announcer or singer sound clearer.

 

[Mr RB]

I think it's just the nature of dynamic mics.

At the time I was looking through a catalogue for small dynamic mics as used in cheap applicances, cellphones, headsets etc and there hundreds of mics all with little charts, and none of the charts looked good.

 

[audioguru]

A dynamic mic is like a little speaker. It has a magnet that has a moving coil around it to generate a signal. The coil is fairly heavy so it needs a fairly strong and heavy diaphragm to move it with sounds so its resonance is at a few thousand Hz which causes a peak in the response.

But an electret mic has a very thin and lightweight conductive film as its diaphragm so its upper frequency response is extended and is flat.