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<DIV dir=ltr align=left><SPAN class=810125919-11082024>I'm actually building my
own version of the Korg PS-3100. I'm calling it the Sketchy Labs
DS-3100. However, mine will have some unique features: Saw, Tri, and
(fully PWMable) Pulse waveforms will be blended with faders. Also,
HP, BP, and LP filter responses will be blended with faders. Finally,
two complete and independent ADSR EGs per key (with hold
functions), one for the filter and one for the VCA, rather than just
one. Also, the filter ADSR control will be bipolar for
weird negative envelope effects.</SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=810125919-11082024></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=810125919-11082024>Each ADSR requires one
2164, the filter and VCA together require one 2164, and the waveform and filter
response faders each require one 2164, per key. That's five 2164s per key,
times 48 keys, so there will be 240 2164s just on the voicecards. I'm
presuming another 10 or so on the front panel controls for a total of 250.
It may be slightly more or slightly less.</SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=810125919-11082024></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=810125919-11082024>My worries with this
beast are: 1) How much heat will the circuitry generate? I'm going to
install a fan inside the case, but I don't know whether it will be sufficient,
particularly since many circuit boards will be stacked about 1 cm apart.
2) Will a 3A+3A power supply be sufficient? 3) Will there be a problem
mixing 48 key outputs together? Will clipping be a problem?
Obviously, all 48 keys will never be played at the same time, but
still.</SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=810125919-11082024></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=810125919-11082024>This is a project that I
have dreamed of doing ever since I started doing synth DIY. I know it's
stupid and ill advised, but it has been a lot of fun so far, and that's really
the whole point. It's going to take me months to build, and that's also
sort of the point. I've designed the VCOs and the voicecards, and built
prototypes that I'm happy with, so once my huge 2164 order arrives, I'll start
building. I still have to design the circuitry downsteam of the
voicecards, and figure out the front panel, but I'm not too worried about
that.</SPAN></DIV><BR>
<DIV dir=ltr lang=en-us class=OutlookMessageHeader align=left>
<HR tabIndex=-1>
<FONT size=2 face=Tahoma><B>From:</B> Synth-diy
[mailto:synth-diy-bounces@synth-diy.org] <B>On Behalf Of </B>Ingo Debus via
Synth-diy<BR><B>Sent:</B> Sunday, August 11, 2024 2:50 AM<BR><B>To:</B> Synth
DIY<BR><B>Subject:</B> Re: [sdiy] Best AVAILABLE OTA for building new
designs?<BR></FONT><BR></DIV>
<DIV></DIV>
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<DIV><BR>
<BLOCKQUOTE type="cite">
<DIV>Am 10.08.2024 um 20:48 schrieb Mike Beauchamp <<A
href="mailto:list@mikebeauchamp.com">list@mikebeauchamp.com</A>>:</DIV><BR
class=Apple-interchange-newline>
<DIV>
<DIV>
<BLOCKQUOTE
style="TEXT-TRANSFORM: none; FONT-STYLE: normal; TEXT-INDENT: 0px; FONT-FAMILY: Helvetica; WHITE-SPACE: normal; LETTER-SPACING: normal; FONT-SIZE: 14px; FONT-WEIGHT: normal; WORD-SPACING: 0px; TEXT-DECORATION: none; font-variant-caps: normal; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px"
type="cite">My latest project is going to require about 250 2164 ICs.
That's not a problem given what I'm paying for them. Yes, in all but
the filter<SPAN
class=Apple-converted-space> </SPAN><BR></BLOCKQUOTE><SPAN
style="TEXT-TRANSFORM: none; FONT-STYLE: normal; TEXT-INDENT: 0px; DISPLAY: inline !important; FONT-FAMILY: Helvetica; WHITE-SPACE: normal; FLOAT: none; LETTER-SPACING: normal; FONT-SIZE: 14px; FONT-WEIGHT: normal; WORD-SPACING: 0px; TEXT-DECORATION: none; font-variant-caps: normal; -webkit-text-stroke-width: 0px; caret-color: rgb(0, 0, 0)">I
don't think I'm the only person here interested in hearing more details about
your project that uses 250 quad VCA's…</SPAN></DIV></DIV></BLOCKQUOTE></DIV>
<DIV><BR></DIV>A Hammond B3 style organ, where every key contact is replaced by
a VCA? 2*61 keys, 9 contacts per key?
<DIV><BR></DIV>
<DIV>Any other ideas?</DIV>
<DIV><BR></DIV>
<DIV>Ingo<BR>
<DIV><BR></DIV></DIV></BODY></HTML>