> For a digital square wave you would want to use band limiting to avoid
> alias artifacts which are quite severe for a square or sawtooth wave. As
> the frequency goes higher both of those waves will begin to look more like
> sine waves as the partials are filtered out. Pretty much every commercial
> digital synth and plugin uses anti-aliased waveforms.

out of interest Chris, do they use wavetables (possible of different
lengths for different octaves) or internal oversampling a la Millers
example in the doc patches?

I can't really speak for any manufacturers but it probably varies based on the hardware being used.