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</head><body style=""><div>Hi Mattias,</div>
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<div>I mean the circuit like this:</div>
<div>http://www.bernacomp.com/elec/lockbox/lockbox_vca2.gif</div>
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<div>So, no.</div>
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<div>Best regards</div>
<div>Simon</div>
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<div><br>> Op 10 februari 2016 om 12:31 schreef Mattias Rickardsson <mr@analogue.org>:<br>> <br>> <br>> Simon,<br>> <br>> what about the temperature dependencies in the transistor case?<br>> Is that control circuit more sensitive for temperature variations?<br>> <br>> /mr<br>> <br>> <br>> On 10 February 2016 at 09:08, Simon Brouwer <simon.o@brousant.nl> wrote:<br>> > Yes it was.<br>> ><br>> > However, this circuit still uses one opamp, a resistor and at least two<br>> > diodes.<br>> > The more straightforward approach adds two resistors, and replaces one diode<br>> > by a<br>> > transistor.<br>> > So this doesn't add much in complexity and cost, and you can control both<br>> > halves of an LM13700 independently.<br>> ><br>> > Best regards<br>> > Simon<br>> ><br>> ><br>> >> Op 9 februari 2016 om 20:20 schreef Mattias Rickardsson <mr@analogue.org>:<br>> ><br>> >><br>> >><br>> >> Aha!<br>> >> It *was* a beautiful trick. :-)<br>> >><br>> >> http://electronotes.netfirms.com/AN399.pdf<br>> >><br>> >> /mr<br>> >><br>> >><br>> >> On 8 February 2016 at 19:09, Ian Fritz <ijfritz@comcast.net> wrote:<br>> >> > The reference to the original Jung article is JAES, 23, 1975. This<br>> >> > method<br>> >> > was widely used in EN projects. I looked at using this method with the<br>> >> > LM13700 to aid people who want to build off of these projects, but who<br>> >> > can't<br>> >> > obtain the CA3080. It's also an easy way to improve S/N by 3dB, as<br>> >> > pointed<br>> >> > out by Serge T. in his EN article from when the chip was new.<br>> >> ><br>> >> > I couldn't wade through Aaron's article either. It sounded like negating<br>> >> > then subtracting? Isn't that the same as adding?<br>> >> ><br>> >> > Ian<br>> >> ><br>> >> ><br>> >> ><br>> >> > On 2/8/2016 2:41 AM, Mattias Rickardsson wrote:<br>> >> >><br>> >> >> On 4 February 2016 at 05:52, <ijfritz@comcast.net> wrote:<br>> >> >>><br>> >> >>> Good grief! Just connect them directly in parallel. An example,<br>> >> >>> complete<br>> >> >>> with the W. Jung trick:<br>> >> >>><br>> >> >>><br>> >> >>> http://electro-music.com/forum/viewtopic.php?highlight=jung+ota&t=50884<br>> >> >><br>> >> >><br>> >> >> What does it do? What is the "trick"?<br>> >> >> I feel like one of the answers in that thread:<br>> >> >> "I hadn't heard of this trick before, is there an article somewhere<br>> >> >> that explains the benefit of drawing bias current from V-? I feel like<br>> >> >> there's something obvious that I'm missing."<br>> >> >><br>> >> >> I spontaneously found Aaron's idea potentially better than nothing,<br>> >> >> but I haven't plunged into it.<br>> >> >><br>> >> >> /mr<br>> >> >><br>> >> ><br>> >> _______________________________________________<br>> >> Synth-diy mailing list<br>> >> Synth-diy@dropmix.xs4all.nl<br>> >> http://dropmix.xs4all.nl/mailman/listinfo/synth-diy<br>> ><br>> > _______________________________________________<br>> > Synth-diy mailing list<br>> > Synth-diy@dropmix.xs4all.nl<br>> > http://dropmix.xs4all.nl/mailman/listinfo/synth-diy<br>> ></div></body></html>