<html><head><meta http-equiv="content-type" content="text/html; charset=utf-8"></head><body dir="auto"><p style="margin: 0px; font-stretch: normal; line-height: normal; font-family: ".SF UI Text"; color: rgb(69, 69, 69);"><span style="font-family: ".SFUIText"; font-size: 17pt;">following up on richie’s reply - thats a good start!</span></p>
<p style="margin: 0px; font-stretch: normal; line-height: normal; font-family: ".SF UI Text"; color: rgb(69, 69, 69); min-height: 20.3px;"><span style="font-family: ".SFUIText"; font-size: 17pt;"></span><br></p>
<p style="margin: 0px; font-stretch: normal; line-height: normal; font-family: ".SF UI Text"; color: rgb(69, 69, 69);"><span style="font-family: ".SFUIText"; font-size: 17pt;">a quick max patch gave me a nice proof of concept, i think it has a nice sound to it - however it also revealed a potential problem.</span></p>
<p style="margin: 0px; font-stretch: normal; line-height: normal; font-family: ".SF UI Text"; color: rgb(69, 69, 69); min-height: 20.3px;"><span style="font-family: ".SFUIText"; font-size: 17pt;"></span><br></p>
<p style="margin: 0px; font-stretch: normal; line-height: normal; font-family: ".SF UI Text"; color: rgb(69, 69, 69);"><span style="font-family: ".SFUIText"; font-size: 17pt;">if the sync input triggering exceeds the oscillation rate of the core, a loss of amplitude is introduced since the core can never reach its outer limits. i hadn’t thought of this before but it’s painfully obvious now!</span></p>
<p style="margin: 0px; font-stretch: normal; line-height: normal; font-family: ".SF UI Text"; color: rgb(69, 69, 69); min-height: 20.3px;"><span style="font-family: ".SFUIText"; font-size: 17pt;"></span><br></p>
<p style="margin: 0px; font-stretch: normal; line-height: normal; font-family: ".SF UI Text"; color: rgb(69, 69, 69);"><span style="font-family: ".SFUIText"; font-size: 17pt;">some kind of expander circuit feels like over engineering, so perhaps this is not the best approach - unless I use some sort of logic gate trickery to only switch once the core has crossed zero at least once?</span></p><br><div id="AppleMailSignature">Sent from outer space</div><div><br>On Sep 15, 2018, at 9:00 PM, Quincas Moreira <<a href="mailto:quincas@gmail.com">quincas@gmail.com</a>> wrote:<br><br></div><blockquote type="cite"><div><div dir="ltr">Paging mr Ian Fritz......</div><br><div class="gmail_quote"><div dir="ltr">On Sat, Sep 15, 2018 at 6:33 PM Richie Burnett <<a href="mailto:rburnett@richieburnett.co.uk">rburnett@richieburnett.co.uk</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">I guess the OP meant the frequency changes sign?<br>
<br>
Homophones "sine" and "sign" in the same sentence always sounds confusing! <br>
At least we haven't had "sinc" and "sync" yet ;-)<br>
<br>
-Richie.<br>
<br>
-----Original Message----- <br>
From: Tom Wiltshire<br>
Sent: Sunday, September 16, 2018 12:02 AM<br>
To: ulfur hansson<br>
Cc: synth-diy mailing list<br>
Subject: Re: [sdiy] Adding "sync" to a Through-Zero Sinewave Oscillator <br>
design<br>
<br>
I thought triangle oscillators didn’t change *sign*, but rather changed <br>
*direction*.<br>
<br>
Changing sign would imply that a waveform at +2V would jump abruptly to -2V. <br>
Changing directions means only that a waveform that has been rising up to <br>
+2V would start falling instead.<br>
<br>
> On 15 Sep 2018, at 23:26, ulfur hansson <<a href="mailto:ulfurh@gmail.com" target="_blank">ulfurh@gmail.com</a>> wrote:<br>
><br>
> hello list!<br>
><br>
> i have been working on a prototype for a through zero quadrature sinecore <br>
> oscillator over the past few weeks, and have been thinking of ways to add <br>
> a novel type of "sync" to the circuit.<br>
><br>
> I love the way traditional triangle core oscillator sync sounds, and much <br>
> prefer it to the harsher sawcore type sync.<br>
><br>
> with trianglecore sync (I hope I understand this correctly) the waveform <br>
> changes sign at trigger points rather than doing a hard reset to 0v, <br>
> right?<br>
><br>
> since my oscillator is through zero, my idea is to implement a switch that <br>
> inverts the incoming v/8 CV everytime the "sync" input exceeds a certain <br>
> threshold.<br>
><br>
> this would (in my mind) effectively only change sign of the sine waveform, <br>
> emulating the triangle core sync i mentioned before.<br>
><br>
> before I start gathering components and laying out a sync prototype board, <br>
> i'd love to see if any of you think this is a ridiculous idea - and if <br>
> there is any literature out there on various methods of sync, i would love <br>
> to learn more about it beyond discharging integrator caps to ground :)<br>
><br>
> thanks so much for your insight!<br>
> all the best,<br>
> -úlfur<br>
> _______________________________________________<br>
> Synth-diy mailing list<br>
> <a href="mailto:Synth-diy@synth-diy.org" target="_blank">Synth-diy@synth-diy.org</a><br>
> <a href="http://synth-diy.org/mailman/listinfo/synth-diy" rel="noreferrer" target="_blank">http://synth-diy.org/mailman/listinfo/synth-diy</a><br>
<br>
<br>
_______________________________________________<br>
Synth-diy mailing list<br>
<a href="mailto:Synth-diy@synth-diy.org" target="_blank">Synth-diy@synth-diy.org</a><br>
<a href="http://synth-diy.org/mailman/listinfo/synth-diy" rel="noreferrer" target="_blank">http://synth-diy.org/mailman/listinfo/synth-diy</a><br>
<br>
<br>
---<br>
This email has been checked for viruses by AVG.<br>
<a href="https://www.avg.com" rel="noreferrer" target="_blank">https://www.avg.com</a> <br>
<br>
_______________________________________________<br>
Synth-diy mailing list<br>
<a href="mailto:Synth-diy@synth-diy.org" target="_blank">Synth-diy@synth-diy.org</a><br>
<a href="http://synth-diy.org/mailman/listinfo/synth-diy" rel="noreferrer" target="_blank">http://synth-diy.org/mailman/listinfo/synth-diy</a><br>
</blockquote></div><br clear="all"><div><br></div>-- <br><div dir="ltr" class="gmail_signature" data-smartmail="gmail_signature"><div dir="ltr"><div>Quincas Moreira<br>Synth Diy Guy</div></div></div>
</div></blockquote></body></html>