AudioGeek wrote:
Indeed I have heard of AC current, but I do belive that audio signals
are in fact a low level DC current. In all my work with Audio, I have
never heard of an AC audio signal. Please let me know if I am wrong
in
this point.

You must not have worked very much with audio in all your work
with audio. Try hooking an oscilloscope to the output of one of
your soundcards, or across a set of speaker terminals and observe
the waveform. Note how the voltage changes rapidly and, indeed,
the "current" "alternates" between positive and negative on a
pretty frequent basis, often thousands of times per second.

Now try reading the audio signal from these devices with a DC
voltmeter. Try it instead with an AC voltmeter. Observe the
rather radical difference in the readings you get. Which is
more accurate, do you suspect? (hint: it ain't the DC voltmeter,
not by a long shot).

Next, take any audio electronic device you have laying around,
play music through it and listen. Now, build a filter which
eliminates all AC and passes only DC current (this would be
called a low-pass filter with a very low cutoff frequency).
What what you expect you'd hear? (hint: nothing at all: since
audio IS AC, and you eliminate the AC, you eliminate the audio).