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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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