>> My research seemed to indicate that at least 3 bits are needed
>> to cover the dynamic range needed for almost any viable sound.

Back in the IBM PC/XT days, there were some programs that produced
intelligible speech from the built-in speaker (which had a 1-bit
connection to something.)  Mind you, it sounded pretty awful, but
it WAS recognizable.  IIRC, it modulated a relatively high frequency
carrier wave.  (eg, send 40KHz to a cheap 8ohm speaker, and it will
probably successfully mechanically integrate that to a voltage around
V+/2; increase the widths of the lows or the highs, and you can get
the code to move forward or back.  Do it fast enough, and you get
full control of the output waveform.)

BillW
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