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<DIV><FONT face=Arial>I am soon to be building an x0b0x 303 clone, the square
wave and resonance don't sound exactly like a 303 and one of the designers
attributes this to the gain of the 303's <!--StartFragment -->
2sa733ap transistors as used in the VCF and VCO circuits of the 303, the
part substituted is 2sa733p. The difference is the 733ap part has a gain of
300-350 while the 733p has 270-310. </FONT></DIV>
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<DIV><FONT face=Arial>I am keen to try to get the classic 303 square wave sound
which is very different (as is well documented) from any other synth, any
pointers on which transitors would be a better substitute (BC327, BC557?) Also
is the gain of the transitor affecting the waveshape or PWM in a strange way in
the 303? Why does it sound SO different?</FONT></DIV>
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<DIV><FONT face=Arial>Details of the x0b0x notes here <A
href="http://www.ladyada.net/make/x0xb0x/mods.html">http://www.ladyada.net/make/x0xb0x/mods.html</A></FONT></DIV>
<DIV><FONT face=Arial></FONT> </DIV>
<DIV><FONT face=Arial>If you listen to this soundfile <A
href="http://www.ladyada.net/make/x0xb0x/samples/pattern2-stereo.mp3">http://www.ladyada.net/make/x0xb0x/samples/pattern2-stereo.mp3</A>
you will hear what I mean about the squarewave, the real 303 is on the
right channel, the x0b0x on the left, if you use winamp you can pan between L
& R to compare.</FONT></DIV>
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<DIV><FONT face=Arial>Thanks for any input!</FONT></DIV>
<DIV><FONT face=Arial></FONT> </DIV>
<DIV><FONT face=Arial>FF</FONT></DIV></BODY></HTML>