noise canceling headphones
On Fri, 20 Jan 2012 13:10:59 -0500, Dick Pierce
wrote:
On 1/19/2012 11:20 PM, RichD wrote:
A noise canceling headphone consists of a headphone,
plus an external microphone fed to an inverting input,
right?
Well, not quite.
It also includes some signal processing, mixing
capability to properly blend the processed mic
signal with the incoming music signal, amplifiers
to power the headphone drivers themselves, the
mechanical packaging to hold it all together, etc.
Why does that cost $40 extra?
It costs extra because of the signal processing,
mixing capability to properly blend the processed
mic signal with the incoming music signal, amplifiers
to power the headphone drivers themselves, the
mechanical packaging to hold it all together, etc.
Where does the energy for all that processing and mixing come from?
?-)
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