PenguiN wrote:
for #1, picture an ideal speaker surface. It has perfect frequency
response all the way down to DC. If you put any waveform on its
inputs, it follows it exactly, even if it's just a pure voltage.

So if I put 3 volts on the speaker, say the surface moves forwards 3
feet. If I put -3 volts on the speaker, it moves backwards 6 feed to
an absolute position (relative to its center position) of -3 feet.

Now, while it's at -3 feet bias, I add a small sine wave to the
signal. The voltage vibrates between -3.1 and -2.9 volts, and the
speaker position, relatively to its neutral 0, vibrates around -3.1
and -2.9 feet.

Again, I can't think of a better way of describing what is happening,
nice one Ken. If you cannot picture what is happening in your head,
then this description should help a lot IMHO.

Mark.
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