
<html><head><meta http-equiv="Content-Type" content="text/html; charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class="">IC2 and IC3 are halfwave rectifiers providing set and reset signal to the flip-flop. There's some detail here that I feel like I'm forgetting - does the flip-flop have to be 90 degrees out of phase for some reason? I can't remember.<div class=""><br class=""><div class="">Then those flip-flop signals feed the FETs that provide the invert/noninvert action on the amplifiers both built around op-amps in IC5.<div class=""><br class=""></div><div class="">Tom<br class=""><div><br class=""><blockquote type="cite" class=""><div class="">On 8 Oct 2024, at 22:58, Sean Ellis <<a href="mailto:tensiontype@hotmail.com" class="">tensiontype@hotmail.com</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><div class="elementToProof" style="font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; font-family: Calibri, Helvetica, sans-serif; font-size: 12pt;">Here's the schematic, wondering what the diodes might be doing here?</div><div class="elementToProof" style="font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; font-family: Calibri, Helvetica, sans-serif; font-size: 12pt;"><br class=""></div><div class="elementToProof" style="font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; font-family: Calibri, Helvetica, sans-serif; font-size: 12pt;"><a href="https://www.hobby-hour.com/electronics/s/oc2-octave.php" id="LPlnk583876" class="">https://www.hobby-hour.com/electronics/s/oc2-octave.php</a></div><div class="elementToProof" style="font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; font-family: Calibri, Helvetica, sans-serif; font-size: 12pt;"><br class=""></div><div class="elementToProof" style="font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; font-family: Calibri, Helvetica, sans-serif; font-size: 12pt;">There's a few nice videos showing it's sound on youtube.</div><div id="appendonsend" style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class=""></div><div style="font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; font-family: Calibri, Helvetica, sans-serif; font-size: 12pt;" class=""><br class=""></div><hr style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; display: inline-block; width: 802.609375px;" class=""><span style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; float: none; display: inline !important;" class=""></span><div id="divRplyFwdMsg" dir="ltr" style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class=""><span style="font-family: Calibri, sans-serif; font-size: 11pt;" class=""><b class="">From:</b> Synth-diy <<a href="mailto:synth-diy-bounces@synth-diy.org" class="">synth-diy-bounces@synth-diy.org</a>> on behalf of Harry Bissell <<a href="mailto:hbissell@wowway.com" class="">hbissell@wowway.com</a>><br class=""><b class="">Sent:</b> Tuesday, 8 October 2024 10:41 PM<br class=""><b class="">To:</b> Tom Wiltshire <<a href="mailto:tom@electricdruid.net" class="">tom@electricdruid.net</a>><br class=""><b class="">Cc:</b> <a href="mailto:synth-diy@synth-diy.org" class="">synth-diy@synth-diy.org</a><span class="Apple-converted-space"> </span><<a href="mailto:synth-diy@synth-diy.org" class="">synth-diy@synth-diy.org</a>><br class=""><b class="">Subject:</b> Re: [sdiy] Boss Octave - was Re: Frequency shifted from BBD?</span><div class=""> </div></div><div style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; font-size: 11pt;" class="">By doing it by switching polarity they avoid the problems of envelope following ( one of my pet peeves, if you recall… :^) and also eliminate the need for an OTA etc. I had not thought of this as a “ring mod” before, it’s an interesting way to view it.<br class="">Mr & Mrs Account<br class=""><br class="">> On Oct 8, 2024, at 2:48 PM, Tom Wiltshire <<a href="mailto:tom@electricdruid.net" class="">tom@electricdruid.net</a>> wrote:<br class="">><br class="">> Yes, that's true. I hadn't thought of it that way, but that's exactly what it's doing. It's essentially a multiplication between the input signal and a siganl that goes "+1, -1, +1, -1,+1,-1, etc" - so, yeah, ring mod.<br class="">><br class="">> No wonder they still have a low pass filter after it! Although you gain some "responsive" qualities, you're also going to get a ton of extra stuff you don't need harmonically. Nonetheless, the dynamics are good. As Benjamin said, about the only other way to do that would be to re-impose them using a compander chip or similar, like the Paia Roctave unit does. That's exactly the other approach, iirc. It uses the constant-amplitude squarewaves, bur then uses the envelope of the original signal to impose the original dynamics on them.<br class="">><br class="">> Tom<br class="">><br class="">>> On 8 Oct 2024, at 11:54, Roman Sowa via Synth-diy <<a href="mailto:synth-diy@synth-diy.org" class="">synth-diy@synth-diy.org</a>> wrote:<br class="">>><br class="">>> Which is basicaly amplitude modulation with supressed carier, or as synth nerds like to call it - ringmodulation. Input is modulated with square wave of half frequency, so the resulting spectrum contains sums and differences of the previously filtered input and square wave spectrum. Upper part can be filtered, and we get shifted down by half fundamental frequency output.<br class="">>><br class="">>> Roman<br class="">>><br class="">>> W dniu 2024-10-08 o 12:31, Tom Wiltshire pisze:<br class="">>>> There's actually one further twist to this. The flip-flop signals are not used directly, but instead used to switch between non-inverted and inverted versions of the input wave. The effect of flipping every other input wavecycle is to produce a new waveform with the fundemental an octave lower. The advantage over using the square directly is that the resulting output changes with changes in the input in a way that the square wave doesn't. This makes the pedal seem more "responsive", since it's not just blasting you with a constant volume square wave all the time - instead the dynamics and harmonics of the octave-down signal can both change.<br class="">>>> Tom<br class="">>>>> On 8 Oct 2024, at 08:20, brianw <<a href="mailto:brianw@audiobanshee.com" class="">brianw@audiobanshee.com</a>> wrote:<br class="">>>>><br class="">>>>> The Boss Octave does not actually shift pitch. The algorithm is completely different.<br class="">>>>><br class="">>>>><br class="">>>>> The analog signal is boosted to the point of extreme clipping, making it effectively a square wave. There's some EQ ahead of this to favor the fundamental rather than the harmonics, but you've probably noticed that harmonics can still slip through. Once the input signal is clipped to a square wave, it is processed with CMOS gates to cut the frequency in half, and the again to one quarter. These represent one octave down and two octaves down. Each of those are square waves, too, so they're processed with a low-pass filter to remove (redundant) harmonics. Finally, the original input is mixed with the one-octave down and two-octave down signals. Voila!<br class="">>>>><br class="">>>>> The Boss Octave technique cannot produce any interval other than one octave down (and two octaves down by repeating part of the process).<br class="">>>>><br class="">>>>> FYI, the digital gate that can drop a square wave by one octave is very simple and cheap, and often there is more than one in the same chip. Thus, the two octaves down signal is practically free.<br class="">>>>><br class="">>>>> Brian<br class="">>>>><br class="">>>>> p.s. I made a decent recreation of this in software until I realized that Logic Studio Pro already has such a plugin that works better than mine.<br class="">>>>><br class="">>>>><br class="">>>>>> On Oct 7, 2024, at 9:49 AM, Didier Leplae <<a href="mailto:didierleplae@yahoo.com" class="">didierleplae@yahoo.com</a>> wrote:<br class="">>>>>>> Thanks for all the replies to this question! It’s all very interesting. I used to have a Boss Octave pedal back in the 80s. I wonder if it also worked with BBDs.<br class="">>>>>><br class="">>>>>><br class="">>>>>> ________________________________________________________<br class="">>>>>> This is the Synth-diy mailing list<br class="">>>>>> Submit email to:<span class="Apple-converted-space"> </span><a href="mailto:Synth-diy@synth-diy.org" class="">Synth-diy@synth-diy.org</a><br class="">>>>>> View archive at:<span class="Apple-converted-space"> </span><a href="https://synth-diy.org/pipermail/synth-diy/" id="OWA45c401fb-0ae5-2ce4-38c5-c06aebb1d4a4" class="OWAAutoLink" data-auth="NotApplicable">https://apac01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fsynth-diy.org%2Fpipermail%2Fsynth-diy%2F&data=05%7C02%7C%7C658d7df83b004be7b48f08dce7dab8b8%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C638640173814326905%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C0%7C%7C%7C&sdata=5dmmbfDAN%2Bc6udhXLw23unHHv3%2Bx9S%2FoeB2WId6a0Ko%3D&reserved=0</a><br class="">>>>>> Check your settings at:<span class="Apple-converted-space"> </span><a href="https://synth-diy.org/mailman/listinfo/synth-diy" id="OWAf91431f1-e135-4ab6-b329-d966924acc03" class="OWAAutoLink" data-auth="NotApplicable">https://apac01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fsynth-diy.org%2Fmailman%2Flistinfo%2Fsynth-diy&data=05%7C02%7C%7C658d7df83b004be7b48f08dce7dab8b8%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C638640173814342707%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C0%7C%7C%7C&sdata=n4rd1kqTty1HXtDfrUa7YvJTvs%2F0m6g%2Fm%2FLhJmboP3Y%3D&reserved=0</a><br class="">>>>>> Selling or trading? Use<span class="Apple-converted-space"> </span><a href="mailto:marketplace@synth-diy.org" class="">marketplace@synth-diy.org</a><br class="">>>> ________________________________________________________<br class="">>>> This is the Synth-diy mailing list<br class="">>>> Submit email to:<span class="Apple-converted-space"> </span><a href="mailto:Synth-diy@synth-diy.org" class="">Synth-diy@synth-diy.org</a><br class="">>>> View archive at:<span class="Apple-converted-space"> </span><a href="https://synth-diy.org/pipermail/synth-diy/" id="OWA44ce107d-63e3-3dc7-df39-f2d062446006" class="OWAAutoLink" data-auth="NotApplicable">https://apac01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fsynth-diy.org%2Fpipermail%2Fsynth-diy%2F&data=05%7C02%7C%7C658d7df83b004be7b48f08dce7dab8b8%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C638640173814350738%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C0%7C%7C%7C&sdata=xUQ65UWvlOBFQeM3Eb%2B9gKgO5H%2B19kefjuDoc04GiGk%3D&reserved=0</a><br class="">>>> Check your settings at:<span class="Apple-converted-space"> </span><a href="https://synth-diy.org/mailman/listinfo/synth-diy" id="OWA01f8f863-6d71-dab8-8538-77556472f8ee" class="OWAAutoLink" data-auth="NotApplicable">https://apac01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fsynth-diy.org%2Fmailman%2Flistinfo%2Fsynth-diy&data=05%7C02%7C%7C658d7df83b004be7b48f08dce7dab8b8%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C638640173814358631%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C0%7C%7C%7C&sdata=%2F5XYtaa4yqNUw5n%2BJu5jiqPjDJ8he4NoTvm2ghVmqg0%3D&reserved=0</a><br class="">>>> Selling or trading? Use<span class="Apple-converted-space"> </span><a href="mailto:marketplace@synth-diy.org" class="">marketplace@synth-diy.org</a><br class="">>> ________________________________________________________<br class="">>> This is the Synth-diy mailing list<br class="">>> Submit email to:<span class="Apple-converted-space"> </span><a href="mailto:Synth-diy@synth-diy.org" class="">Synth-diy@synth-diy.org</a><br class="">>> View archive at:<span class="Apple-converted-space"> </span><a href="https://synth-diy.org/pipermail/synth-diy/" id="OWAa02fc2b3-6d72-f37d-b4cd-b5942f7cc395" class="OWAAutoLink" data-auth="NotApplicable">https://apac01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fsynth-diy.org%2Fpipermail%2Fsynth-diy%2F&data=05%7C02%7C%7C658d7df83b004be7b48f08dce7dab8b8%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C638640173814366399%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C0%7C%7C%7C&sdata=MhvZ9BhlnIM4%2Bs86b42GW4Pw1io0yCn4x8qsG3G58C4%3D&reserved=0</a><br class="">>> Check your settings at:<span class="Apple-converted-space"> </s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tter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; display: inline-block; width: 802.609375px;" class=""><span style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; float: none; display: inline !important;" class=""></span><div id="divRplyFwdMsg" dir="ltr" style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class=""><span style="font-family: Calibri, sans-serif; font-size: 11pt;" class=""><b class="">From:</b> Synth-diy <<a href="mailto:synth-diy-bounces@synth-diy.org" class="">synth-diy-bounces@synth-diy.org</a>> on behalf of Harry Bissell <<a href="mailto:hbissell@wowway.com" class="">hbissell@wowway.com</a>><br class=""><b class="">Sent:</b> Tuesday, 8 October 2024 10:41 PM<br class=""><b class="">To:</b> Tom Wiltshire <<a href="mailto:tom@electricdruid.net" class="">tom@electricdruid.net</a>><br class=""><b class="">Cc:</b> <a href="mailto:synth-diy@synth-diy.org" class="">synth-diy@synth-diy.org</a><span class="Apple-converted-space"> </span><<a href="mailto:synth-diy@synth-diy.org" class="">synth-diy@synth-diy.org</a>><br class=""><b class="">Subject:</b> Re: [sdiy] Boss Octave - was Re: Frequency shifted from BBD?</span><div class=""> </div></div><div style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; font-size: 11pt;" class="">By doing it by switching polarity they avoid the problems of envelope following ( one of my pet peeves, if you recall… :^) and also eliminate the need for an OTA etc. I had not thought of this as a “ring mod” before, it’s an interesting way to view it.<br class="">Mr & Mrs Account<br class=""><br class="">> On Oct 8, 2024, at 2:48 PM, Tom Wiltshire <<a href="mailto:tom@electricdruid.net" class="">tom@electricdruid.net</a>> wrote:<br class="">><br class="">> Yes, that's true. I hadn't thought of it that way, but that's exactly what it's doing. It's essentially a multiplication between the input signal and a siganl that goes "+1, -1, +1, -1,+1,-1, etc" - so, yeah, ring mod.<br class="">><br class="">> No wonder they still have a low pass filter after it! Although you gain some "responsive" qualities, you're also going to get a ton of extra stuff you don't need harmonically. Nonetheless, the dynamics are good. As Benjamin said, about the only other way to do that would be to re-impose them using a compander chip or similar, like the Paia Roctave unit does. That's exactly the other approach, iirc. It uses the constant-amplitude squarewaves, bur then uses the envelope of the original signal to impose the original dynamics on them.<br class="">><br class="">> Tom<br class="">><br class="">>> On 8 Oct 2024, at 11:54, Roman Sowa via Synth-diy <<a href="mailto:synth-diy@synth-diy.org" class="">synth-diy@synth-diy.org</a>> wrote:<br class="">>><br class="">>> Which is basicaly amplitude modulation with supressed carier, or as synth nerds like to call it - ringmodulation. Input is modulated with square wave of half frequency, so the resulting spectrum contains sums and differences of the previously filtered input and square wave spectrum. Upper part can be filtered, and we get shifted down by half fundamental frequency output.<br class="">>><br class="">>> Roman<br class="">>><br class="">>> W dniu 2024-10-08 o 12:31, Tom Wiltshire pisze:<br class="">>>> There's actually one further twist to this. The flip-flop signals are not used directly, but instead used to switch between non-inverted and inverted versions of the input wave. The effect of flipping every other input wavecycle is to produce a new waveform with the fundemental an octave lower. The advantage over using the square directly is that the resulting output changes with changes in the input in a way that the square wave doesn't. This makes the pedal seem more "responsive", since it's not just blasting you with a constant volume square wave all the time - instead the dynamics and harmonics of the octave-down signal can both change.<br class="">>>> Tom<br class="">>>>> On 8 Oct 2024, at 08:20, brianw <<a href="mailto:brianw@audiobanshee.com" class="">brianw@audiobanshee.com</a>> wrote:<br class="">>>>><br class="">>>>> The Boss Octave does not actually shift pitch. The algorithm is completely different.<br class="">>>>><br class="">>>>><br class="">>>>> The analog signal is boosted to the point of extreme clipping, making it effectively a square wave. There's some EQ ahead of this to favor the fundamental rather than the harmonics, but you've probably noticed that harmonics can still slip through. Once the input signal is clipped to a square wave, it is processed with CMOS gates to cut the frequency in half, and the again to one quarter. These represent one octave down and two octaves down. Each of those are square waves, too, so they're processed with a low-pass filter to remove (redundant) harmonics. Finally, the original input is mixed with the one-octave down and two-octave down signals. Voila!<br class="">>>>><br class="">>>>> The Boss Octave technique cannot produce any interval other than one octave down (and two octaves down by repeating part of the process).<br class="">>>>><br class="">>>>> FYI, the digital gate that can drop a square wave by one octave is very simple and cheap, and often there is more than one in the same chip. Thus, the two octaves down signal is practically free.<br class="">>>>><br class="">>>>> Brian<br class="">>>>><br class="">>>>> p.s. I made a decent recreation of this in software until I realized that Logic Studio Pro already has such a plugin that works better than mine.<br class="">>>>><br class="">>>>><br class="">>>>>> On Oct 7, 2024, at 9:49 AM, Didier Leplae <<a href="mailto:didierleplae@yahoo.com" class="">didierleplae@yahoo.com</a>> wrote:<br class="">>>>>>> Thanks for all the replies to this question! It’s all very interesting. I used to have a Boss Octave pedal back in the 80s. I wonder if it also worked with BBDs.<br class="">>>>>><br class="">>>>>><br class="">>>>>> ________________________________________________________<br class="">>>>>> This is the Synth-diy mailing list<br class="">>>>>> Submit email to:<span class="Apple-converted-space"> </span><a href="mailto:Synth-diy@synth-diy.org" class="">Synth-diy@synth-diy.org</a><br class="">>>>>> View archive at:<span class="Apple-converted-space"> </span><a href="https://synth-diy.org/pipermail/synth-diy/" id="OWA7f13318b-cdc0-f311-9779-e060ef87a00e" class="OWAAutoLink" data-auth="NotApplicable">https://apac01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fsynth-diy.org%2Fpipermail%2Fsynth-diy%2F&data=05%7C02%7C%7C658d7df83b004be7b48f08dce7dab8b8%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C638640173814326905%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C0%7C%7C%7C&sdata=5dmmbfDAN%2Bc6udhXLw23unHHv3%2Bx9S%2FoeB2WId6a0Ko%3D&reserved=0</a><br class="">>>>>> Check your settings at:<span class="Apple-converted-space"> </span><a href="https://synth-diy.org/mailman/listinfo/synth-diy" id="OWA6919a8e5-d1b2-154d-286c-f1553da4d485" class="OWAAutoLink" data-auth="NotApplicable">https://apac01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fsynth-diy.org%2Fmailman%2Flistinfo%2Fsynth-diy&data=05%7C02%7C%7C658d7df83b004be7b48f08dce7dab8b8%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C638640173814342707%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C0%7C%7C%7C&sdata=n4rd1kqTty1HXtDfrUa7YvJTvs%2F0m6g%2Fm%2FLhJmboP3Y%3D&reserved=0</a><br class="">>>>>> Selling or trading? Use<span class="Apple-converted-space"> </span><a href="mailto:marketplace@synth-diy.org" class="">marketplace@synth-diy.org</a><br class="">>>> ________________________________________________________<br class="">>>> This is the Synth-diy mailing list<br class="">>>> Submit email to:<span class="Apple-converted-space"> </span><a href="mailto:Synth-diy@synth-diy.org" class="">Synth-diy@synth-diy.org</a><br class="">>>> View archive at:<span class="Apple-converted-space"> </span><a href="https://synth-diy.org/pipermail/synth-diy/" id="OWAa603da5f-0080-9674-3c21-6b29a4f06610" class="OWAAutoLink" data-auth="NotApplicable">https://apac01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fsynth-diy.org%2Fpipermail%2Fsynth-diy%2F&data=05%7C02%7C%7C658d7df83b004be7b48f08dce7dab8b8%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C638640173814350738%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C0%7C%7C%7C&sdata=xUQ65UWvlOBFQeM3Eb%2B9gKgO5H%2B19kefjuDoc04GiGk%3D&reserved=0</a><br class="">>>> Check your settings at:<span class="Apple-converted-space"> </span><a href="https://synth-diy.org/mailman/listinfo/synth-diy" id="OWA824192de-eb2b-5461-834f-0874f816cb9b" class="OWAAutoLink" data-auth="NotApplicable">https://apac01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fsynth-diy.org%2Fmailman%2Flistinfo%2Fsynth-diy&data=05%7C02%7C%7C658d7df83b004be7b48f08dce7dab8b8%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C638640173814358631%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C0%7C%7C%7C&sdata=%2F5XYtaa4yqNUw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