"Chris Morriss" wrote in message
...
In message , Peter Scott
writes




I SPICE simulated a 20V pk-pk sine wave of 1kHz, being clipped to 18V
pk-pk by a couple of Schottky diodes and a pair of voltage sources. I
added a series resistor to give the effect of an amp 'soft-clipping'.

THD (for the first 16 harmonics) was 0.77%.

3rd of 0.37%
5th of 0.385%
7th of 0.362%
9th of 0.30%
11th of 0.23%
13th of 0.145%
15th of 0.0835

So even with only a small amount of fairly soft clipping, the harmonics
are not starting to drop off quickly until above the 11th, although the
amount of energy in them is quite small.

Interesting. Of course the sim will model a perfectly shaped wave
and perhaps just a little more rounding would reduce the higher harmonics
even more? Looks like SPICE is even better than when I last used.
The modelling you've done is very clever. Thanks

Peter Scott