Doepfer

Rats.  Now I really wish I had an A-164 to try this instead of my positive-only, modified A-119/142s. 

If hard sync resets the VCO to the lowest point, and my threshold is at 0V, maybe it will still work for me. 

Nick

Sent from the future

> On Nov 14, 2013, at 6:09 AM, <dmitry.shtatnov@gmail.com> wrote:
> 
> Hi.
> 
> Try this route:
> 
> Oscillator's wave to Comparator Pos. input. (Neg. to GND). Comparator's output to logic AND with Gate. The AND's output to ADSR and back to Comparator's Pos. at the same time. I can confirm it but in theory it should help to delay the Gate signal to the nearest zero-crossing of the wave.
> 
> 
> 
> ---In doepfer_a100@yahoogroups.com, <modular_steve@...> wrote:
> 
> Hello again! Is there a module that resets waves every time they're triggered? I think clicking might be reduced if a wave was always triggered at the beginning of its cycle. The DSI Tempest does this pretty successfully. Just food for thought :). Regards, Steve
>

Hello Nick

Am 14.11.2013 13:47, schrieb Nicholas Keller:
> Rats.  Now I really wish I had an A-164 to try this instead of my
> positive-only, modified A-119/142s.
>
> If hard sync resets the VCO to the lowest point, and my threshold is at
> 0V, maybe it will still work for me.
Since you have modified modules you seem to be able to solder.

If you want to avoid clicking with the A-142 at low frequencies, then 
simply increase the capacitor
If it is an A-142(-1) I suggest to add a 47nf cap to the existing cap
If it is an A-142-4 I suggest to add a 100nF cap to the existing cap
See
http://www.doepfer.de/DIY/a100_capacitors.htm

I have a A-142-4 and have the lower two envelopes with larger caps then 
the upper two envelopes

Florian

Thanks Florian (and thanks again for the SPV-355 info!)

I will look into changing the caps, but the mod I was referring to was the "External Input to Comparator" that I posted here a week or two ago, which I did to access the comparators in both the A-199 and A-142.  

But as Dieter pointed out, the more I considered this patch, the less I believed it would work.  The AND output would be a gate stream at audio rate, rather than a held-high gate.  If Dieter's future "gate delay" module could be adapted to delay based on the FIRST zero crossing ONLY, that might work, but I wouldn't know how to design such a circuit.  

Dieter, would the signal based on CV changes be similar to the Gate Out on the A-156?

Nick

Sent from the future

> On Nov 14, 2013, at 8:39 AM, Florian Anwander <fanwander@mnet-online.de> wrote:
> 
> Hello Nick
> 
> Am 14.11.2013 13:47, schrieb Nicholas Keller:
> > Rats. Now I really wish I had an A-164 to try this instead of my
> > positive-only, modified A-119/142s.
> >
> > If hard sync resets the VCO to the lowest point, and my threshold is at
> > 0V, maybe it will still work for me.
> Since you have modified modules you seem to be able to solder.
> 
> If you want to avoid clicking with the A-142 at low frequencies, then 
> simply increase the capacitor
> If it is an A-142(-1) I suggest to add a 47nf cap to the existing cap
> If it is an A-142-4 I suggest to add a 100nF cap to the existing cap
> See
> http://www.doepfer.de/DIY/a100_capacitors.htm
> 
> I have a A-142-4 and have the lower two envelopes with larger caps then 
> the upper two envelopes
> 
> Florian
>

Nick,

please find my answers written inline.

Best wishes
Dieter Doepfer

> But as Dieter pointed out, the more I considered this patch, the
> less I believed it would work.  The AND output would be a gate
> stream at audio rate, rather than a held-high gate.  If Dieter's
> future "gate delay" module could be adapted to delay based on the
> FIRST zero crossing ONLY, that might work, but I wouldn't know
> how to design such a circuit.

That's the mentioned flipflop circuit. The output will turn high as soon as
the first pulse of the "gate stream at audio rate" appears and stay high
until the gate turns low.

> Dieter, would the signal based on CV changes be similar to the Gate Out on
the A-156?

No. It's a very simple analog circuit. One solution is a low frequency high
pass followed by comparators to separate the negative and positive pitch
changes. Another solution is to compare the original stepped CV with the
slewed CV (generated by means of a slew limiter). Such a circuit is often
called "new pitch detector".

oops