slippyr4 wrote:
> The only thing i'm uncertain of is how long olin's circuit will take
> for the waveform to stabilise once i start outputing a square wave.

The circuit is just 3 simple single pole R-C filters cascaded.  Worst case
you could take the sum of the three series resistors times the sum of the 3
filter capacitors and get a time constant as a rough upper bound on the time
frame of the "memory" in this circuit.  In practise the first output cycle
will be somewhat different because all the capacitors start at 1/2 the
supply voltage when they would be at different phases during continuous
operation.  The second cycle will be a lot closer, and I doubt you'd be able
to distinguish the third cycle from the remaining ones on a scope.  In other
words, in practise the sound will appear to start and stop instantaneously.
If you keep the output in high impedence state when not producing sound,
there shouldn't be a pop when the sound is started.

> Anyone with more experience like to take a guess?

Why not use a little logic and think about it yourself?  Even better, build
it and look at the output.

> or is that the sort of thing that can be simulated?

Obviously, since several people have already do that.


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