Logitech "noise-cancelling" microphone
I'm having some issues with the logitech claim of "noise cancelling" on this microphone, which I see a lot of people like.
is there any circuitry in the microphone other than the microphone itself, and the mute switch? "noise cancelling" implies that it actively detects and cancels out noise in some manner, but without any other circuitry that is pretty much impossible... the only thing I can think of is that the lower cutoff frequency is specified at 100 Hz, which is double the 50Hz that most other similar mics specify... just blocking some low-frequency noise hardly counts as "noise-cancelling"... Although, I would imagine normal road noise would be relatively low-frequency... perhaps I will have to build an adjustable high-pass filter sometime and try it out...
Perhaps I'll get up the motivation to hook a microphone up to my oscilloscope, stick it in FFT mode, and drive around looking at the frequency spectrum to see how much low-frequency noise there really is.
Not to claim it isn't in some way better than a "standard" microphone, I just think the "noise cancelling" claim is marketing BS... ESPECIALLY if they didn't even add in any circuitry, they just chose a microphone with a larger lower cutoff frequency... So I'm curious.
What this could mean, though, is that if cutting off more low-frequency noise is the real cause for the increased sensitivity despite road noise, then anyone could potentially just add a simple resistor/capacitor high-pass filter and improve the response of their microphone in the car... a 10 cent fix for a $10 price difference between that mic and others! :cool: