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<div class="elementToProof"><span style="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0); background-color: rgb(255, 255, 255);">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="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0); background-color: rgb(255, 255, 255);">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="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0); background-color: rgb(255, 255, 255);">Perhaps he'll come by and shed some light. fwiw.</span></div>
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<div class="elementToProof"><span style="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0); background-color: rgb(255, 255, 255);">d.<br>
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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" color="#000000"><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>
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<div class="" style="word-wrap:break-word; line-break:after-white-space">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.
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<div class="">Here’s a video of me taking it apart, looking at the PCBs, and putting it back together: </div>
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<div class=""><a href="https://www.youtube.com/watch?v=-ndWT1LWqJ8" class="">https://www.youtube.com/watch?v=-ndWT1LWqJ8</a></div>
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<div>Aaron Lanterman, Prof. of ECE, Georgia Tech<br class="">
My blog on Education and Innovation: <a href="https://edupocalypsenow.wordpress.com" class="">https://edupocalypsenow.wordpress.com</a><br class="">
My blog on Electronics and Programming: <a href="https://lantertronics.blogspot.com" class="">https://lantertronics.blogspot.com</a><br class="">
My YouTube channel on Electronics and Programming: <a href="https://www.youtube.com/c/lantertronics" class="">https://www.youtube.com/c/lantertronics</a></div>
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