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<DIV dir=ltr align=left><SPAN class=546332618-26122022><FONT face=Calibri>Yep, I
only use 2164 in all my filter designs. I built one filter with 13700 when
I got started with electronics, and it was great, but the 2164 is just so
convenient and works so well.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=546332618-26122022><FONT
face=Calibri></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=546332618-26122022><FONT face=Calibri>It
also makes great VCAs, VCOs, multipliers, crossfaders, linear FM and
through-zero FM drivers, frequency shifters, and was even at the heart of the
original Quadra, which was functionally identical to the Buchla
281.</FONT></SPAN></DIV><BR>
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<FONT size=2 face=Tahoma><B>From:</B> Synth-diy
[mailto:synth-diy-bounces@synth-diy.org] <B>On Behalf Of </B>Darren Shorsky via
Synth-diy<BR><B>Sent:</B> Monday, December 26, 2022 10:03 AM<BR><B>To:</B>
synth-diy mailing list; Lanterman, Aaron D<BR><B>Subject:</B> Re: [sdiy] Buchla
291e teardown<BR></FONT><BR></DIV>
<DIV></DIV>
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Non-UBC Email]</FONT></TD></TR></TBODY></TABLE>
<DIV class=elementToProof><SPAN
style="BACKGROUND-COLOR: rgb(255,255,255); FONT-FAMILY: Calibri, Helvetica, sans-serif; COLOR: rgb(0,0,0); FONT-SIZE: 12pt">If
it uses the 2164..... it may be similar to any one of the filters that Dave
Dixon has built over the years.</SPAN></DIV>
<DIV class=elementToProof><SPAN
style="BACKGROUND-COLOR: rgb(255,255,255); FONT-FAMILY: Calibri, Helvetica, sans-serif; COLOR: rgb(0,0,0); FONT-SIZE: 12pt">The
2164 being his go to chip for almost everything..... he also doesn't use
vactrols as far as I'm aware.</SPAN></DIV>
<DIV class=elementToProof><SPAN
style="BACKGROUND-COLOR: rgb(255,255,255); FONT-FAMILY: Calibri, Helvetica, sans-serif; COLOR: rgb(0,0,0); FONT-SIZE: 12pt">Perhaps
he'll come by and shed some light. fwiw.</SPAN></DIV>
<DIV class=elementToProof><SPAN
style="BACKGROUND-COLOR: rgb(255,255,255); FONT-FAMILY: Calibri, Helvetica, sans-serif; COLOR: rgb(0,0,0); FONT-SIZE: 12pt"><BR></SPAN></DIV>
<DIV class=elementToProof><SPAN
style="BACKGROUND-COLOR: rgb(255,255,255); FONT-FAMILY: Calibri, Helvetica, sans-serif; COLOR: rgb(0,0,0); FONT-SIZE: 12pt">d.<BR></SPAN></DIV>
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<DIV dir=ltr id=divRplyFwdMsg><FONT style="FONT-SIZE: 11pt"
face="Calibri, sans-serif"><B>From:</B> Synth-diy
<synth-diy-bounces@synth-diy.org> on behalf of Lanterman, Aaron D via
Synth-diy <synth-diy@synth-diy.org><BR><B>Sent:</B> December 26, 2022 9:51
AM<BR><B>To:</B> synth-diy mailing list
<synth-diy@synth-diy.org><BR><B>Subject:</B> [sdiy] Buchla 291e
teardown</FONT>
<DIV> </DIV></DIV>
<DIV style="WORD-WRAP: break-word">I’ve always wondered if the 291e uses
Vactrols like the original 291. It doesn’t! It’s completely different. It uses
SSM2164 VCAs, so I’m guessing it’s probably closer to the State Variable Filter
in the Oberheim OB-MX.
<DIV><BR></DIV>
<DIV>Here’s a video of me taking it apart, looking at the PCBs, and putting it
back together: </DIV>
<DIV><BR></DIV>
<DIV><A
href="https://www.youtube.com/watch?v=-ndWT1LWqJ8">https://www.youtube.com/watch?v=-ndWT1LWqJ8</A></DIV>
<DIV><BR></DIV>
<DIV>
<DIV>
<DIV>
<DIV>Aaron Lanterman, Prof. of ECE, Georgia Tech<BR>My blog on
Education and Innovation: <A
href="https://edupocalypsenow.wordpress.com">https://edupocalypsenow.wordpress.com</A><BR>My
blog on Electronics and Programming: <A
href="https://lantertronics.blogspot.com">https://lantertronics.blogspot.com</A><BR>My
YouTube channel on Electronics and Programming: <A
href="https://www.youtube.com/c/lantertronics">https://www.youtube.com/c/lantertronics</A></DIV>
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