noise canceling headphones
On Jan 20, 5:20*pm, RichD wrote:
A noise canceling headphone consists of a headphone,
plus an external microphone fed to an inverting input,
right?
Why does that cost $40 extra?
--
Rich
You cannot just stick a microphone and invert the signal and hope it
will cancel noise. You need to match the amplitudes at different
frequencies and this requires an adaptive filter.
hardy
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