Cgs synth

See the small "ringing" at the bottom of the lower "square" wave? You should
be seeing that at about 5-10 times the amplitude on both the top and bottom
excursions from a squarewave input. You are seeing ringing, but it appears
to be happening across the whole signal. Do you have the correct capacitor
in the feedback loop?

Ken

>I still don't fully understand what I should expect from this module. I
>listened to the sample file in the yahoo group archive, and since I don't
>know what the original signal was, I can't glean much insight.
>
>Since you said that an oscilloscope can help choosing an op-amp that does
>the right thing, here's a screen shot of a square wave run through my
>Grinder section, with both controls set to their middle position:
>http://studionebula.com/images/CGS-WM-graph.jpg
>
>Here's an audio file of its output, same square-wave input:
>http://studionebula.com/sounds/modular/CGS_WM_test.mp3
>In this file I start with both controls rotated fully CCW. I turn one all
>the way up and then all the way back down, then the other all the way up and
>all the way back down, then one up to its middle position and leave it
>there, then turn the other up to its middle position. If you can't tell
>which knob is which, then you're understanding my point. :-)
>
>Thanks in advance to any other Wave Multiplier owners who can take a
>look/listen to these files and tell me whether or not mine seems to be
>operating properly.
>
>--Adam
>
>> -----Original Message-----
>> From: sasami@... [mailto:sasami@...]
>> Sent: Sunday, September 25, 2005 3:58 PM
>> To: cgs_synth@yahoogroups.com
>> Subject: RE: [cgs_synth] Finally! The Wave Multiplier is built.
>>
>> Basically the grinder is exploiting exactly what you DON'T want in a
>> typical
>> servo system (such as the feedback of an op-amp. It causes the op-amp to
>> overcompensate, then overcompensate in the reverse direction etc,
>> effectively causing a high pitch ringing on the output wave. If you have
>> an
>> oscilliscope, it can help choosing a chip.
>>
>> Ken
>>
>>
>> >I am also happy with my recently completed Wave Multiplier, although I am
>> >somewhat non-plussed by the Grinder section. It seems that its two
>> controls
>> >have basically the same effect on the timbre, although with slightly
>> >different ranges of operation and some interdependence. It also sounds
>> more
>> >like a resonant filter than something I'd describe as a "grinder". Do
>> other
>> >Wave Multiplier owners observe similar behavior in their grinders, or is
>> >there something wrong with mine?
>> >
>> >--Adam
>> >
>> >
>> >
>> >
>> >
>> >
>> >The CGS Modular Synth home page: http://www.cgs.synth.net/
>> >
>> >Yahoo! Groups Links
>> >
>> >
>> >
>> >
>> >
>> >
>> >
>> >
>> _______________________________________________________________________
>> Ken Stone sasami@... or sasami@...
>> Modular Synth PCBs for sale <http://www.blaze.net.au/~sasami/synth/>
>> Australian Miniature Horses & Ponies <http://www.blaze.net.au/~sasami/>
>>
>>
>>
>>
>> The CGS Modular Synth home page: http://www.cgs.synth.net/
>>
>> Yahoo! Groups Links
>>
>>
>>
>>
>>
>>
>>
>
>
>
>
>
>The CGS Modular Synth home page: http://www.cgs.synth.net/
>
>Yahoo! Groups Links
>
>
>
>
>
>
>
>

_______________________________________________________________________
Ken Stone sasami@... or sasami@...
Modular Synth PCBs for sale <http://www.blaze.net.au/~sasami/synth/>
Australian Miniature Horses & Ponies <http://www.blaze.net.au/~sasami/>