Doepfer

Hi there Doepfer techs,

Yesterday I received my second A157 and after installing I did a testrun. 
With an LFO using for clock it worked very well. 
However using the internal clock output from one of my A154's the A157 didn't respond. 
Is this due to a too low sensitivity of the A157 clock input?

Cheers,

Jacco Ville

Hello Jacco

Am 07.04.2016 um 08:29 schrieb jaccoville@yahoo.com [Doepfer_a100]:
> However using the internal clock output from one of my A154's the A157 didn't respond.
> Is this due to a too low sensitivity of the A157 clock input?
What do you mean with the A-154s "internal clock output" ? The clock out 
on the frontpanel?

I have to admit I haven't tried it with the A-154 yet, but with the 
A-155 and with various other clocksources (TR-606 / TR-808 / SBX80) and 
never had any problem

Florian

Hello Florian,

Yes, the front output from the A154 feed from it's internal clock. 

Once I noticed that the A157 wasn't responding, although sometimes just one step, I verified the A154's clock output with my other  A154 input and even the A160-1 and A160-2 which worked flawlessly.  

So, I guess it has something to do with a low(er) sensitivity of the A157's clock input. 

Cheers

Jacco Ville



Verstuurd vanaf mijn iPhone 5 Black OPS Edition

> Op 7 apr. 2016 om 10:22 heeft Florian Anwander fanwander@mnet-online.de [Doepfer_a100] <Doepfer_a100@yahoogroups.com> het volgende geschreven:
> 
> Hello Jacco
> 
> Am 07.04.2016 um 08:29 schrieb jaccoville@yahoo.com [Doepfer_a100]:
> > However using the internal clock output from one of my A154's the A157 didn't respond.
> > Is this due to a too low sensitivity of the A157 clock input?
> What do you mean with the A-154s "internal clock output" ? The clock out 
> on the frontpanel?
> 
> I have to admit I haven't tried it with the A-154 yet, but with the 
> A-155 and with various other clocksources (TR-606 / TR-808 / SBX80) and 
> never had any problem
> 
> Florian
>

> Hi there Doepfer techs,
>
> Yesterday I received my second A157 and after installing I did a testrun.
> With an LFO using for clock it worked very well.
> However using the internal clock output from one of my A154's the A157 didn't respond.
> Is this due to a too low sensitivity of the A157 clock input?
>
> Cheers,
>
> Jacco Ville

That's strange as during the Superbooth last week I used the clock output of the A-154 all the time to trigger the A-157 (and all
other devices that used the clock). Maybe the PW setting of A-154 clock is too small (near 0%) or too high (near 100%).

Best wishes
Dieter Doepfer

Yes Dieter, 

Gutemorgen :-) ... Exactly that's what I didn't pay attention to. 
The pulsewidth....
But because all other clockmodules responded well to that same pulse. 

Thanks the wakeupcall. 

Jacco Ville


Verstuurd vanaf mijn iPhone 5 Black OPS Edition

Op 7 apr. 2016 om 10:45 heeft yahoo@doepfer.de [Doepfer_a100] <Doepfer_a100@yahoogroups.com> het volgende geschreven:

>> Hi there Doepfer techs,
>> 
>> Yesterday I received my second A157 and after installing I did a testrun.
>> With an LFO using for clock it worked very well.
>> However using the internal clock output from one of my A154's the A157 didn't respond.
>> Is this due to a too low sensitivity of the A157 clock input?
>> 
>> Cheers,
>> 
>> Jacco Ville
> 
> That's strange as during the Superbooth last week I used the clock output of the A-154 all the time to trigger the A-157 (and all
> other devices that used the clock). Maybe the PW setting of A-154 clock is too small (near 0%) or too high (near 100%).
> 
> Best wishes
> Dieter Doepfer
> 
> 
> 
> 
> 
> ------------------------------------
> 
> ------------------------------------
> 
> 
> ------------------------------------
> 
> Yahoo Groups Links
> 
> 
>

> Yes Dieter,
>
> Gutemorgen :-) ... Exactly that's what I didn't pay attention to.
> The pulsewidth....
> But because all other clockmodules responded well to that same pulse.
>
> Thanks the wakeupcall.
>
> Jacco Ville

It has to do with the fact that the A-157 has a microcontroller that "polls" the clock input. If the incoming pulse is too short it
may overlook the clock signal. Hardware based clock modules (like A-160, A-161) do not have this problem as they are made from
hardware digital logic elements (no microcontrollers). I had a discussion with other module manufacturers during the Superbooth and
we think about an expansion of the eurorack standard that includes also specs like minimum trigger length (1 ms or 5ms are under
discussion) and minimum gate/trigger levels. Some manufacturers voted for 3V (because they use internal controllers with 3.3V
supplies and want to keep the circuits as simple as possible) but I'd recommend at least 5V even if this requires additional level
shifters (for some of our modules these level shifters are 30% or more of the circuit, e.g. A-160-1/2, A-161).

Best wishes
Dieter Doepfer

Hello  Dieter

Am 07.04.2016 um 11:49 schrieb yahoo@doepfer.de [Doepfer_a100]:
>   I had a discussion with other module manufacturers during the Superbooth and
> we think about an expansion of the eurorack standard that includes also specs like minimum trigger length (1 ms or 5ms are under
> discussion) and minimum gate/trigger levels. Some manufacturers voted for 3V (because they use internal controllers with 3.3V
> supplies and want to keep the circuits as simple as possible) but I'd recommend at least 5V even if this requires additional level
> shifters (for some of our modules these level shifters are 30% or more of the circuit, e.g. A-160-1/2, A-161).
I'd vote for a threshold level as small as possible.
The highest trigger voltages I know are 12V. To my experience even 
retriggering due to transient overshoots does not happen with such high 
trigger signals (on the usual cricuits) with a threshold down to 1 Volt.
Looking at the 3.3V argument I'd vote for a threshold level of 2V too.
About the minimum length I vote for 5ms, because it makes software based 
debouncing much easier.

Florian

> Hello  Dieter
>
> Am 07.04.2016 um 11:49 schrieb yahoo@doepfer.de [Doepfer_a100]:
> >   I had a discussion with other module manufacturers during the Superbooth and
> > we think about an expansion of the eurorack standard that includes also specs like minimum trigger length (1 ms or 5ms are under
> > discussion) and minimum gate/trigger levels. Some manufacturers voted for 3V (because they use internal controllers with 3.3V
> > supplies and want to keep the circuits as simple as possible) but I'd recommend at least 5V even if this requires
> additional level
> > shifters (for some of our modules these level shifters are 30% or more of the circuit, e.g. A-160-1/2, A-161).
> I'd vote for a threshold level as small as possible.
> The highest trigger voltages I know are 12V. To my experience even
> retriggering due to transient overshoots does not happen with such high
> trigger signals (on the usual cricuits) with a threshold down to 1 Volt.
> Looking at the 3.3V argument I'd vote for a threshold level of 2V too.
> About the minimum length I vote for 5ms, because it makes software based
> debouncing much easier.
>
> Florian

Hi Florian,

I agree if you mean the input threshold. In most of our modules there is an npn transistor at the input which has a threshold value
in the 1V range. But the output level of gate and trigger signals should be at least 5V from my point of view. In this case you are
always on the safe side. And one also have to consider that gate and trigger signals are also sometimes "abused" for other
functions, e.g. as sync input for VCOs so that the VCO starts from the same waveform position (an important feature especially for
bass sounds with low VCO frequencies), or as "on/off CV" e.g. to open a VCF or VCA. User's also mix gate and trigger signals e.g.
with A-138 (e.g. as a simple sequencer). For these applications a 2 or 3V level would be not sufficient (I don't know a VCO that
would sync with 2V only). We will see what will be the result of the eurorack manufacturers agreements in terms of these additional
specs.

Cheers
Dieter

Am 07.04.2016 um 12:21 schrieb yahoo@doepfer.de [Doepfer_a100]:
> But the output level of gate and trigger signals should be at least 5V from my point of view.
Agreed!

> On Apr 7, 2016, at 3:21 AM, yahoo@doepfer.de [Doepfer_a100] <Doepfer_a100@yahoogroups.com> wrote:
> 
> We will see what will be the result of the eurorack manufacturers agreements in terms of these additional
> specs.

This will be the hard part - getting the manufacturers to agree on “standards” seems to be a problem in the past. It might be different now, especially coming from major players like you Dieter. It was hard getting the ~100 members of the Mostly Modular Trade Association (MMTA) to agree on stuff sometimes. A lot of independent thinkers out there making modules.
-James

James Husted, Designer, Synthwerks LLC • www.synthwerks.com • james@synthwerks.com • info@synthwerks.com