On the A-137 page there are some green/black figures demonstrating
control setting effects. They seem to be real oscilloscope captures,
as I was able to reproduce them with reasonable accuracy. So, my A-
137 seems to work normally.

Some observations (and some might think nit-picking):

- Of the above mentioned figures "Changing the Symmetry"
and "Changing the Harmonics" pictures are swapped.

- The above mentioned figures are said to demonstrate: "changing a
control from low (left picture) to high (right picture)". This
doesn't necessarily translate to from full counter clockwise to full
clockwise - at least in my unit.

- It is best to start experimenting with Harmonics at 9'o clock or
more. First I assumed, that full counter clockwise was somewhat
neutral setting.

- The Harmonics control works "a little bit like the resonance
control of a filter". It doesn't sound at all like a filter though.

- The diagrams in the manual showing some triangle wave folding are
indeed diagrammatic. I can't reproduce them.

Best regards
Jari Jokinen

--- In Doepfer_a100@yahoogroups.com , "Tim Stinchcombe" <timothy@...>
wrote:

>
> Hi Jari,
>
> At roughly the same settings as you give, my A-137 gives a very
> similar trace to yours. Because of the 4 stages acting one after

the

> other, it is quite hard to see the effect of each stage and/or
> controls in isolation. I suspect the diagrams in the manual are
> rather diagrammatic of what is going on, rather than the literal
> truth, but I'll study the circuit a little, and see if I can answer
> some of your other questions.
>
> Tim
>
> --- In Doepfer_a100@yahoogroups.com , "jalmari3" <jari.jokinen@>
> wrote:
> >
> > I can't duplicate the folded triangle waveforms shown in the A-

137

> > manual (chapter 2). The shown waveforms consist of straight

lines,

> but
> > I get rounded waveforms.
> >
> > Here is an example oscilloscope view:
> > http://www.esnips.com/doc/278f44e2-ce2a-4ff1-8f17-1f7ef5d795d7/A-
> > 137_weirdness_1
> > (I hope the link isn't too long for Yahoo.)
> > The settings are:
> > - All CV inputs at full counter clockwise and unplugged
> > - Input level at 12'o clock
> > - Multiples at 9'o clock
> > - Folding level at 12'o clock
> > - Symmetry at 12'o clock
> > - Harmonics at full counter clockwise
> >
> > Questions:
> > - Is this the expected output on these settings
> > - Why does a triangle input get rounded
> > - What settings should give the straight line waveforms shown in
> the
> > manual
> >
> >
> > Best regards and thank you for your time
> > Jari Jokinen
> >
>