Ahh... the Schumann custom stuff. I hear it's very nice stuff.

Regards,
Kevin

--- In Doepfer_a100@yahoogroups.com , "ps_minor" <pscottm@h...> wrote:
> hey that sounds nearly identical to my new favorite device, a box a
friend of
> mine has put into production recently, called simply the PLL.
it's an amazing
> thing.. mine will have CV added soon, and an arpegiator for
cycling through
> harmonics. it has germainium overdrive circuits built into the
mixer controls
> and a waveshaper on final output. very musical device!
>
> have a look:
>
> http://members.toast.net/photos/album.asp user=pscottm&album=
> schumann%20PLL
>
> also, i just loaned him a doepfer mini power supply/bus board &
blank panel
> so he can develop one in euro module format. (actually, it'll just
be the PLL
> 'front end' osc control circuit, not the multiplier/divider, or
mixer.
> -psm
>
>
>
> Lindholm" <andreas.k.lindholm@t...> wrote:
> > That sounds interesting to me although I don't completey grasap
it, but the
> > wobbling and inaccuracy in this case could be more advatageous as
an
> effect
> > than a pure VCO it seems to me... when did this module come up on
the
> > agenda I didn't even know it was something Doepfer had in
mind....
> >
> >
> > ----- Original Message -----
> > From: "Bakis Sirros" <synth_freak_2000@y...>
> > To: "Doepfer_a100 group" < doepfer_a100@yahoogroups.com >
> > Sent: Thursday, June 26, 2003 6:06 PM
> > Subject: 1 a brief explanation about the uses of a
PLL
> > VCO.(from doepfer.)
> >
> >
> > > dieter says:
> > > "a PLL and it's application is not very easy to
> > > understand. I will try to write an explanation and
> > > publish it on our web site as soon as we publish the
> > > preliminary page for the PLL module (no A-100 number
> > > so far).
> > > Here is a simplified explanation: A PLL is a linear
> > > rectangle VCO with a frequency comparator that
> > > compares the frequency of the internal PLL-VCO with an
> > > external frequency (master frequency) - e.g. the
> > > rectangle output of "normal" A-100 VCO - and makes
> > > the the internal VCO frequency equal to the external
> > > frequency. Or better said: it tries to adjust the
> > > internal frequency so that it becomes equal to the
> > > external frequency. The problem is the frequency
> > > comparator - even called phase comparator - that
> > > generates a kind of a correction voltage that becomes
> > > zero if both frequencies are identical. Different
> > > versions with different advantages/disadvantages of
> > > frequency comparators are available. Some types of
> > > comparators e.g. will "lock" even at multiples of the
> > > frequencies. Another problem is the time that is
> > > necessary until the PLL-VCO is adjusted. It will
> > > always take some time until the new frequency of the
> > > PLL-VCO is reached (similar to portamento). The time
> > > constant of the internal low pass filter (not an audio
> > > low pass but a low pass/slew limiter for the
> > > correction CV) defines the time until the new
> > > frequency is reached. But this time has not to be too
> > > short otherwise the frequency of the PLL-VCO will
> > > "wobble" around the master frequency. These
> > > "disadvantages" lead to additional musical
> > > applications like portamento effects or wobbling
> > > frequencies according to the type of frequency
> > > comparator and time constant of the PLL low pass
> > > filter.
> > > Another application is frequency multiplication in
> > > combination with an external frequency divider. For
> > > this the output of the PLL-VCO is processed through a
> > > frequency divider (e.g. A-160, A-161, A-163) before it
> > > is fed to the PLL frequency comparator. In this case
> > > the frequency of the PLL-VCO will be a multiple of the
> > > master frequency. E.g if the the A-163 is used and
> > > adjusted to dividing factor 5 the frequency of the
> > > PLL-VCO will be 5 times the frequency of the master
> > > VCO. Consequently frequency division (A-163) leads to
> > > frequency multiplication with the PLL circuit. In
> > > combination with the PLL low pass frequency several
> > > effects can be realized (frequency multiplication with
> > > portamento or wobbling). The frequency multiplication
> > > can even be used to drive a graphic VCO. If your
> > > graphic VCO e.g. has 8 steps (e.g. A-155) and you use
> > > a frequency divider with factor 8 in the PLL feedback
> > > the output of the graphic VCO has the same frequency
> > > as the master VCO. Another application is the
> > > generation of pseudo-harmonics (not real harmonics as
> > > only rectangle waves are available).
> > >
> > > I hope this explanation will help and not cause more
> > > confusion. I know that the PLL is not very easy to
> > > understand.
> > > Best wishes
> > > Dieter Doepfer"
> > >
> > >
> > >
> > > INTERESTING OF COURSE,YES!
> > > bakis.
> > >
> > >
> > >
> > >
> > > =====
> > > synthfreak(parallel worlds)
> > > athens-greece
> > > 1 group owner
> > >
> > > __________________________________
> > > Do you Yahoo!
> > > SBC Yahoo! DSL - Now only $29.95 per month!
> > > http://sbc.yahoo.com
> > >
> > >
> > > To unsubscribe from this group, send an email to:
> > > doepfer_a100-unsubscribe@yahoogroups.com
> > >
> > >
> > >
> > > Your use of Yahoo! Groups is subject to
http://docs.yahoo.com/info/terms/
> > >
> > >