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<DIV dir=ltr align=left><SPAN class=168282317-26082016><FONT color=#0000ff
size=2 face=Arial>To answer Quincas's question below: It is relatively
hard to make a sine wave directly without using a self-oscillating filter or a
digital wavetable. It is harder to get superior tracking in a filter than
in a well-designed VCO. Also, it is pretty hard to shape a sine into
anything else, because it has no sharp edges or straight lines. It is very
straightforward to shape triangles or saws into the other waves with rectifiers
and plus-minus amps, which are easy to design.</FONT></SPAN></DIV>
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<DIV dir=ltr align=left><SPAN class=168282317-26082016><FONT color=#0000ff
size=2 face=Arial>Also, a sine shaper to get a sine with a THD of about 0.5 to
1.0% is convenient and cheap.</FONT></SPAN></DIV>
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<DIV>I have another question about the sinewave issue (btw I love my sines,
use them all the time, but only the filters in oscillation give me perfect
sines)</DIV>
<DIV id=AppleMailSignature>Is there not a way to make a sine core oscillator
and derive the other waves from it? Like a filter with fixed high resonance
for the sine, a comparator for the square etc...</DIV>
<DIV>Why doesn't anybody do that?<BR><BR>Quincas Moreira<SPAN
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