Doepfer

Okay, I think the A154 as currently proposed doesn't do variable step 
length and midi sync at the same time, I believe the clock input jack 
shorts out the clock generator.

Now I'm back to thinking about buying an A163 VC divider for to get 
variable step length with midi sync. But ringmod's question got me 
thinking. The A163 doesn't have a reset input like the A160 clock 
divider does. Won't it end up in an indeterminate state when you reset 
the master clock? That would mean the clock pulses from the A163 could 
be as much as 180 degrees out of phase with the master clock, a 
half-step delay.

Has anyone tried this? Is there any way to do what I want to do?

Joe

--- In Doepfer_a100@y..., "Joe Buechler" <buechlerjoe@t...> wrote:
> Okay, I think the A154 as currently proposed doesn't do variable 
step 
> length and midi sync at the same time, I believe the clock input 
jack 
> shorts out the clock generator.

hi Joe, judging by the A190 manual, the A190 already has a divisor 
built in and it also reponds to Program Change n. the chart is also 
there at this url.

http://www.doepfer.de/a100_man/a190_man.htm

logically speaking, the A190 sends out a 50% PW duty cycle. the step 
time would be based on the divisor you set the A190 to be at. so the 
A154 would probably accept the duty cycle as is. now the Variable 
pulse shaper on the A154 would shape the A190 pulse cycle plus or 
minus from its 50% PW duty cycle. once it is shaped manually or by 
voltage control, the newly shaped pulse cycle, which is the same 
length as the A190 50% pulse duty but with a different pulse shape, 
would clock the A155's thru the buss connectors. 
> 
> Now I'm back to thinking about buying an A163 VC divider for to get 
> variable step length with midi sync. But ringmod's question got me 
> thinking. The A163 doesn't have a reset input like the A160 clock 
> divider does. Won't it end up in an indeterminate state when you 
reset 
> the master clock? 

you could avoid this problem by simply multing the clock output from 
the A190 so it goes to the A154 and the A163 , so that if you reset 
the A190 then the A154 and A163 would always be in sync(or phase). 
the A154 would accept the reset pulse from the A190 to do the stop 
and start functions and the A163 will always sync itself to the clock 
out of the A190 regardless of the A190 reset output.

now it would be a wise option to use a buffered multiple for multing 
the clock from A190 to clock the A154, A160/161 and the A163. i would 
use the Analogue Solutions MX224 Mixer / Inverter / Buffer, which is 
a 4hp module(small and has 2 inverted and 4 normal buffered outputs), 
to do the multing to have precise voltages to avoid any delays and 
keep things tight and in sync. the plus side to this module is, it 
has inverted outputs, as well, to do ping pong style panning and 
delays. hope this helps.

regards,
RM


That would mean the clock pulses from the A163 could 

> be as much as 180 degrees out of phase with the master clock, a 
> half-step delay.
> 
> Has anyone tried this? Is there any way to do what I want to do?
> 
> Joe

--- In Doepfer_a100@y..., bakis Sirros <synth_freak_2000@y...> wrote:
> hi ringmod,
> as far as i understand,the a154 pwm controls are for
> the on-board vc clock source ONLY.so,you can't shape
> the a190 50% pulse wth the a154.
> bakis.

hi Bakis, i am sure doepfer could build the shaper to perform the 
function on the A190 clock. but if the A154 can not shape the Clock 
Duty cycle of the A190, would you be able to use the Analoge Systems 
RS50 Trigger, Voltage Controlled Pulse Shaper & Voltage Controlled DC 
Level Shifter to do the job? look at the url below. 

http://www.analoguesystems.co.uk/modules/rs50.htm 

 i hope the A154 has the Pulse Shaper on board to shape the clock's 
input, as well as its own clock.

Regards,
RM 

> 
> 
> --- ringmod45 <ringmod45@y...> wrote:
> > --- In Doepfer_a100@y..., "Joe Buechler"
> > <buechlerjoe@t...> wrote:
> > > Okay, I think the A154 as currently proposed
> > doesn't do variable 
> > step 
> > > length and midi sync at the same time, I believe
> > the clock input 
> > jack 
> > > shorts out the clock generator.
> > 
> > hi Joe, judging by the A190 manual, the A190 already
> > has a divisor 
> > built in and it also reponds to Program Change n.
> > the chart is also 
> > there at this url.
> > 
> > http://www.doepfer.de/a100_man/a190_man.htm
> > 
> > logically speaking, the A190 sends out a 50% PW duty
> > cycle. the step 
> > time would be based on the divisor you set the A190
> > to be at. so the 
> > A154 would probably accept the duty cycle as is. now
> > the Variable 
> > pulse shaper on the A154 would shape the A190 pulse
> > cycle plus or 
> > minus from its 50% PW duty cycle. once it is shaped
> > manually or by 
> > voltage control, the newly shaped pulse cycle, which
> > is the same 
> > length as the A190 50% pulse duty but with a
> > different pulse shape, 
> > would clock the A155's thru the buss connectors. 
> > > 
> > > Now I'm back to thinking about buying an A163 VC
> > divider for to get 
> > > variable step length with midi sync. But ringmod's
> > question got me 
> > > thinking. The A163 doesn't have a reset input like
> > the A160 clock 
> > > divider does. Won't it end up in an indeterminate
> > state when you 
> > reset 
> > > the master clock? 
> > 
> > you could avoid this problem by simply multing the
> > clock output from 
> > the A190 so it goes to the A154 and the A163 , so
> > that if you reset 
> > the A190 then the A154 and A163 would always be in
> > sync(or phase). 
> > the A154 would accept the reset pulse from the A190
> > to do the stop 
> > and start functions and the A163 will always sync
> > itself to the clock 
> > out of the A190 regardless of the A190 reset output.
> > 
> > now it would be a wise option to use a buffered
> > multiple for multing 
> > the clock from A190 to clock the A154, A160/161 and
> > the A163. i would 
> > use the Analogue Solutions MX224 Mixer / Inverter /
> > Buffer, which is 
> > a 4hp module(small and has 2 inverted and 4 normal
> > buffered outputs), 
> > to do the multing to have precise voltages to avoid
> > any delays and 
> > keep things tight and in sync. the plus side to this
> > module is, it 
> > has inverted outputs, as well, to do ping pong style
> > panning and 
> > delays. hope this helps.
> > 
> > regards,
> > RM
> > 
> > 
> > That would mean the clock pulses from the A163 could
> > 
> > > be as much as 180 degrees out of phase with the
> > master clock, a 
> > > half-step delay.
> > > 
> > > Has anyone tried this? Is there any way to do what
> > I want to do?
> > > 
> > > Joe
> > 
> > 
> 
> 
> =====
> synthfreak(parallel worlds)
> athens-greece
> [Doepfer_a100] group owner-moderator
> 
> __________________________________________________
> Do you Yahoo!?
> U2 on LAUNCH - Exclusive greatest hits videos
> http://launch.yahoo.com/u2

hi ringmod,
as far as i understand,the a154 pwm controls are for
the on-board vc clock source ONLY.so,you can't shape
the a190 50% pulse wth the a154.
bakis.



--- ringmod45 <ringmod45@yahoo.com> wrote:
> --- In Doepfer_a100@y..., "Joe Buechler"
> <buechlerjoe@t...> wrote:
> > Okay, I think the A154 as currently proposed
> doesn't do variable 
> step 
> > length and midi sync at the same time, I believe
> the clock input 
> jack 
> > shorts out the clock generator.
> 
> hi Joe, judging by the A190 manual, the A190 already
> has a divisor 
> built in and it also reponds to Program Change n.
> the chart is also 
> there at this url.
> 
> http://www.doepfer.de/a100_man/a190_man.htm
> 
> logically speaking, the A190 sends out a 50% PW duty
> cycle. the step 
> time would be based on the divisor you set the A190
> to be at. so the 
> A154 would probably accept the duty cycle as is. now
> the Variable 
> pulse shaper on the A154 would shape the A190 pulse
> cycle plus or 
> minus from its 50% PW duty cycle. once it is shaped
> manually or by 
> voltage control, the newly shaped pulse cycle, which
> is the same 
> length as the A190 50% pulse duty but with a
> different pulse shape, 
> would clock the A155's thru the buss connectors. 
> > 
> > Now I'm back to thinking about buying an A163 VC
> divider for to get 
> > variable step length with midi sync. But ringmod's
> question got me 
> > thinking. The A163 doesn't have a reset input like
> the A160 clock 
> > divider does. Won't it end up in an indeterminate
> state when you 
> reset 
> > the master clock? 
> 
> you could avoid this problem by simply multing the
> clock output from 
> the A190 so it goes to the A154 and the A163 , so
> that if you reset 
> the A190 then the A154 and A163 would always be in
> sync(or phase). 
> the A154 would accept the reset pulse from the A190
> to do the stop 
> and start functions and the A163 will always sync
> itself to the clock 
> out of the A190 regardless of the A190 reset output.
> 
> now it would be a wise option to use a buffered
> multiple for multing 
> the clock from A190 to clock the A154, A160/161 and
> the A163. i would 
> use the Analogue Solutions MX224 Mixer / Inverter /
> Buffer, which is 
> a 4hp module(small and has 2 inverted and 4 normal
> buffered outputs), 
> to do the multing to have precise voltages to avoid
> any delays and 
> keep things tight and in sync. the plus side to this
> module is, it 
> has inverted outputs, as well, to do ping pong style
> panning and 
> delays. hope this helps.
> 
> regards,
> RM
> 
> 
> That would mean the clock pulses from the A163 could
> 
> > be as much as 180 degrees out of phase with the
> master clock, a 
> > half-step delay.
> > 
> > Has anyone tried this? Is there any way to do what
> I want to do?
> > 
> > Joe
> 
> 


=====
synthfreak(parallel worlds)
athens-greece
[Doepfer_a100] group owner-moderator

__________________________________________________
Do you Yahoo!?
U2 on LAUNCH - Exclusive greatest hits videos
http://launch.yahoo.com/u2

> hi Joe, judging by the A190 manual, the A190 already has a divisor 
> built in and it also reponds to Program Change n. 

Hi ringmod

Program Change isn't CV, though. I clock the A155 from the A190 all 
the time for midi sync, but when I want variable step length, I clock 
the A155 from the A147 VC LFO, and patch the A155 pre out back to the 
A147 to control the length of each step. You can't control the A190 
divisor with a CV from the A155.

The A154 clock generator, as I understand it, will work identically to 
the A147 for this purpose, with the exception that is also has PWM.

I have two problems with this setup: No quantization of step length, 
and no midi sync. A VC divider would solve both of them, but as I 
mentioned, I'm not sure that the A163 will work correctly because it 
can't be reset when the master clock is reset.

So, I'm back to where I started. Instead of a clock generator, I'd 
like the A154 to have a VC divider, with PWM.

Joe

Hi Joe,
I had an idea that nearly worked with respect to this:

> thinking. The A163 doesn't have a reset input like the A160 clock 
> divider does. Won't it end up in an indeterminate state when you 
reset 
> the master clock? That would mean the clock pulses from the A163 
could 
> be as much as 180 degrees out of phase with the master clock, a 
> half-step delay.
> 
> Has anyone tried this? Is there any way to do what I want to do?

The idea was to hold the 163 at 'divide by 1' whilst in a 'reset' 
state, then let it jump back to the required 'divide by n' when the 
reset is removed (and which by assumption also re-starts the main 
clock). Hopefully this means it starts dividing again from the right 
point. I did this by switching the CV controlling the 'divide by n' 
through a 150, with the other side at ground, and set the 163 so that 
the ground input gave 'divide by 1'. The 'reset' then controls the 
150. The 'fly in the ointment' turned out to be a couple of 
capacitors having a smoothing effect on the CV input to the 163, so 
it cannot see instaneous jumps in CV - it quickly ramps 
through 'divide by 2', 'divide by 3' etc. to eventually get 
to 'divide by n'. I'm assuming the caps are there for stability 
purposes - whether they could be reduced sufficiently to allow this 
idea to work (it may not even be a very good one at that!) and still 
be stable, I don't know, I'll think some more on it...

Tim

Hi Timothy

> I had an idea that nearly worked with respect to this:
> The idea was to hold the 163 at 'divide by 1' whilst in a 'reset' 
> state, then let it jump back to the required 'divide by n' when the 
> reset is removed (and which by assumption also re-starts the main 
> clock). Hopefully this means it starts dividing again from the right 
> point. I did this by switching the CV controlling the 'divide by n' 
> through a 150, 

A good one, too! Too bad it didn't work out.

> I'm assuming the caps are there for stability 
> purposes - whether they could be reduced sufficiently to allow this 
> idea to work (it may not even be a very good one at that!) and still 
> be stable, I don't know ...

Yeah, I'm starting to have doubts about it myself...

The basic goal is to be able to control the length of each sequencer 
step using the bottom row of A155 knobs. I've done this with the A147 
VC LFO as described in the A155 user's manual, and it will work 
the same with the proposed A154 clock generator. Neither allow midi 
sync (when the VC control of rate is in use, bakis), and the 
continuous control is difficult to adjust without any sort of 
quantization.

I'm not an engineer, maybe a VC clock divider idea isn't the right 
approach. It isn't obvious that the change in divisor would be fast 
enough to control the sequencer accurately. Perhaps a software LFO 
that can either be synced to a master clock or free-running, and whose 
rate can be adjusted in increments by a control voltage.

Joe

hi Joe, i think you just solved the problem, hypothethically speaking.
the A190 does have a software LFO in it. now, the only snag is that 
it is only free running. 

a couple of questions to Mr.Doepfer.

would it be possible to have the software LFO sync to midi clock?

would the software LFO be accurate enough to perform as a clock 
source for the A154?

would it be possible to have a divider for the software Lfo?

if the A190 could be somehow reprogrammed to have the LFO sync, this 
would solve problem, i guess.

Joe, i am currently using The Encore Expressionist, it has 3 LFO's 
which can be modulated on separate midi channels and has a re-trig 
parameter to sync the LFO to the number of midi clocks that are 
inputted into the Expressionist.

i think, IIRC, you mentioned before that you own the MCV 24. if the 
MCV 24 has sync LFO's, you could probably use the MCV24 to do the job.

regards,
RM

.
> 
> I'm not an engineer, maybe a VC clock divider idea isn't the right 
> approach. It isn't obvious that the change in divisor would be fast 
> enough to control the sequencer accurately. Perhaps a software LFO 
> that can either be synced to a master clock or free-running, and 
whose 

> rate can be adjusted in increments by a control voltage.
> 
> Joe

What about the A191's MIDI clock sync'ed LFO?


--- In Doepfer_a100@y..., "ringmod45" <ringmod45@y...> wrote:
> hi Joe, i think you just solved the problem, hypothethically 
speaking.
> the A190 does have a software LFO in it. now, the only snag is that 
> it is only free running. 
> 
> a couple of questions to Mr.Doepfer.
> 
> would it be possible to have the software LFO sync to midi clock?
> 
> would the software LFO be accurate enough to perform as a clock 
> source for the A154?
> 
> would it be possible to have a divider for the software Lfo?
> 
> if the A190 could be somehow reprogrammed to have the LFO sync, 
this 
> would solve problem, i guess.
> 
> Joe, i am currently using The Encore Expressionist, it has 3 LFO's 
> which can be modulated on separate midi channels and has a re-trig 
> parameter to sync the LFO to the number of midi clocks that are 
> inputted into the Expressionist.
> 
> i think, IIRC, you mentioned before that you own the MCV 24. if the 
> MCV 24 has sync LFO's, you could probably use the MCV24 to do the 
job.
> 
> regards,
> RM
> 
> .
> > 
> > I'm not an engineer, maybe a VC clock divider idea isn't the 
right 
> > approach. It isn't obvious that the change in divisor would be 
fast 
> > enough to control the sequencer accurately. Perhaps a software 
LFO 

> > that can either be synced to a master clock or free-running, and 
> whose 
> > rate can be adjusted in increments by a control voltage.
> > 
> > Joe

Hi Joe,
I can see better now what's going on with the 163. The 
capacitor 'getting in the way' of step changes to the CV is part of a 
low-pass filter: thus lowering its value shouldn't cause any 
stability problems in itself. However, presumably there is a reason 
for the filtering, and I can only assume that this is to prevent any 
weird interaction with the software in the PIC microcontroller that 
actually does the division. Thus to determine if the 163 could be 
used in the way you want would need some input from Dieter and co. as 
to how it would behave under such conditions. If it requires anything 
like my idea to set it to 'divide by 1' in order to reset it so that 
it responds to step changes sensibly, then it may require quite a 
cumbersome set-up in practice, and it starts to sound like it needs 
to be the dedicated function you are asking for!

Presumably you are anticipating that in use such a function would 
still require very careful set up so that the total number of clock 
periods across all 8 steps turns out to be a reasonably low multiple 
of 8 itself, so that if the sequencer is free running it does 
occasionally appear to be in sync with everything else? To me this 
sounds like quite a complicated feature (but interesting!). I shall 
carry on thinking about it in the wider sense though!

Tim

--- In Doepfer_a100@y..., "Joe Buechler" <buechlerjoe@t...> wrote:
> Hi Timothy
> 
> > I had an idea that nearly worked with respect to this:
> > The idea was to hold the 163 at 'divide by 1' whilst in a 'reset' 
> > state, then let it jump back to the required 'divide by n' when 
the 
> > reset is removed (and which by assumption also re-starts the main 
> > clock). Hopefully this means it starts dividing again from the 
right 
> > point. I did this by switching the CV controlling the 'divide by 
n' 
> > through a 150, 
> 
> A good one, too! Too bad it didn't work out.
> 
> > I'm assuming the caps are there for stability 
> > purposes - whether they could be reduced sufficiently to allow 
this 
> > idea to work (it may not even be a very good one at that!) and 
still 
> > be stable, I don't know ...
> 
> Yeah, I'm starting to have doubts about it myself...
> 
> The basic goal is to be able to control the length of each 
sequencer 
> step using the bottom row of A155 knobs. I've done this with the 
A147 
> VC LFO as described in the A155 user's manual, and it will work 
> the same with the proposed A154 clock generator. Neither allow midi 
> sync (when the VC control of rate is in use, bakis), and the 
> continuous control is difficult to adjust without any sort of 
> quantization.
> 
> I'm not an engineer, maybe a VC clock divider idea isn't the right 
> approach. It isn't obvious that the change in divisor would be fast 
> enough to control the sequencer accurately. Perhaps a software LFO 
> that can either be synced to a master clock or free-running, and 
whose 

> rate can be adjusted in increments by a control voltage.
> 
> Joe

--- In Doepfer_a100@y..., "code_pig" <code_pig@y...> wrote:
> What about the A191's MIDI clock sync'ed LFO?

My A191 doesn't have a CV input jack. Where on the A191 shall I patch 
the Pre Out jack of the A155 to, in order to control step length? 

The same applies to the MCV24 and A190.
> 
> 
> --- In Doepfer_a100@y..., "ringmod45" <ringmod45@y...> wrote:
> > hi Joe, i think you just solved the problem, hypothethically 
> speaking.
> > the A190 does have a software LFO in it. now, the only snag is 
that 
> > it is only free running. 
> > 
> > a couple of questions to Mr.Doepfer.
> > 
> > would it be possible to have the software LFO sync to midi clock?
> > 
> > would the software LFO be accurate enough to perform as a clock 
> > source for the A154?
> > 
> > would it be possible to have a divider for the software Lfo?
> > 
> > if the A190 could be somehow reprogrammed to have the LFO sync, 
> this 
> > would solve problem, i guess.
> > 
> > Joe, i am currently using The Encore Expressionist, it has 3 LFO's 
> > which can be modulated on separate midi channels and has a re-trig 
> > parameter to sync the LFO to the number of midi clocks that are 
> > inputted into the Expressionist.
> > 
> > i think, IIRC, you mentioned before that you own the MCV 24. if 
the 

> > MCV 24 has sync LFO's, you could probably use the MCV24 to do the 
> job.
> > 
> > regards,
> > RM
> > 
> > .
> > > 
> > > I'm not an engineer, maybe a VC clock divider idea isn't the 
> right 
> > > approach. It isn't obvious that the change in divisor would be 
> fast 
> > > enough to control the sequencer accurately. Perhaps a software 
> LFO 
> > > that can either be synced to a master clock or free-running, and 
> > whose 
> > > rate can be adjusted in increments by a control voltage.
> > > 
> > > Joe