On Thu, 15 Jul 2004 10:33:08 -0700, Roy Lewallen
wrote:

Oh, if it's something you built anyway, you might consider using
something like an LM386 for the audio output stage. Besides providing
considerable gain (which might eliminate some other stages), it'll drive
an 8 ohm earpiece with no problem. And it's reasonably efficient.

Well using an op-amp did cross my mind, Roy, but it's cheating in my
book. I like to use discretes so I get a better idea of what's going
on and it's more of a challenge to get right!
--

"What is now proved was once only imagin'd." - William Blake, 1793.