Doepfer

I was playing around with the Oddity softsynth the other day and got
thinking--I've got more than enough oscillators on my modular (4) to
make some amazing duophonic sounds.

How would I go about this?  I've got the basic Doepfer MIDI-CV
converter and an M-Audio Axiom controller...obviously the problem
would be figuring out how to assign each of the two voices.  Can I do
this with my current equipment?

Hi List,

having another look at the quadrature LFO and the cool looking companion quad VCA i stumbled upon one feature that i miss in the current design of the quadrature LFO: a reset/sync input for the quadrature LFO. I believe that this is a simple yet very important feature for such a module. I'll want to use the module for creating sweeping FX sounds, and these require a defined starting point of the quadrature modulation. Also when using the module in the audio range a sync in would greatly expand possible results.

Another idea would be adding four switches to the quad VCA that switch an inverter into the control signal path of the the respective VCA; possibly three-way switches that switch between normal, "x-> x*(-1)" and "x-> 5V-x" modes (where the first inverter mode basically "mirrors" the control signal around zero which would be most interesting for processing control signals, and the second mode would be more along the logic of a "crossfader" and mainly interesting for processing audio signals).

Apart from these suggestions i am *very much* looking forward to these modules as described on the doepfer site :-)
-- 
Der GMX SmartSurfer hilft bis zu 70% Ihrer Onlinekosten zu sparen! 
Ideal für Modem und ISDN: http://www.gmx.net/de/go/smartsurfer

Hi,

   have made duophonic patches using the Kenton Pro-2000.  To do this,
I use the two separate channels, one set to respond to the highest
note, one to the lowest.  Then, you treat each channel as a separate
but identical patch; each with its own oscillators, EGs filters VCas
and anything else.  You can then add any global effects (reverb,
phaser etc).  Lots of fun.  It does mean if you only press one key,
both channels sound.

As for the A190, I don't think this has a second channel.  You would
either need a second module, or an upgrade to a dual channel Midi-CV
converter.

Yours Aye

Stuadh

--- In Doepfer_a100@yahoogroups.com, "travesty14850"
<travesty14850@...> wrote:

>
> I was playing around with the Oddity softsynth the other day and got
> thinking--I've got more than enough oscillators on my modular (4) to
> make some amazing duophonic sounds.
> 
> How would I go about this?  I've got the basic Doepfer MIDI-CV
> converter and an M-Audio Axiom controller...obviously the problem
> would be figuring out how to assign each of the two voices.  Can I do
> this with my current equipment?
>

hello denis,
i think your suggestions about a sync input and the
switches are cool.
dieter?

best regards,
Bakis.


--- "Denis Gökdag" <q-art@gmx.net> wrote:

> Hi List,
> 
> having another look at the quadrature LFO and the
> cool looking companion quad VCA i stumbled upon one
> feature that i miss in the current design of the
> quadrature LFO: a reset/sync input for the
> quadrature LFO. I believe that this is a simple yet
> very important feature for such a module. I'll want
> to use the module for creating sweeping FX sounds,
> and these require a defined starting point of the
> quadrature modulation. Also when using the module in
> the audio range a sync in would greatly expand
> possible results.
> 
> Another idea would be adding four switches to the
> quad VCA that switch an inverter into the control
> signal path of the the respective VCA; possibly
> three-way switches that switch between normal, "x->
> x*(-1)" and "x-> 5V-x" modes (where the first
> inverter mode basically "mirrors" the control signal
> around zero which would be most interesting for
> processing control signals, and the second mode
> would be more along the logic of a "crossfader" and
> mainly interesting for processing audio signals).
> 
> Apart from these suggestions i am *very much*
> looking forward to these modules as described on the
> doepfer site :-)
> -- 
> Der GMX SmartSurfer hilft bis zu 70% Ihrer
> Onlinekosten zu sparen! 
> Ideal für Modem und ISDN:
> http://www.gmx.net/de/go/smartsurfer
> 


Bakis Sirros - Parallel Worlds
[Doepfer_a100] group owner
http://www.parallel-worlds-music.com
http://www.myspace.com/parallelworldsmusic
http://www.shimarecords.co.uk
http://www.rubber.gr
Athens-Greece


 
____________________________________________________________________________________
Have a burning question?  
Go to www.Answers.yahoo.com and get answers from real people who know.

i agree about the reset input, that would be so cool.

best wishes

ingo



--- In Doepfer_a100@yahoogroups.com, Bakis Sirros 
<synth_freak_2000@...> wrote:
>
> hello denis,
> i think your suggestions about a sync input and the
> switches are cool.
> dieter?
> 
> best regards,
> Bakis.
> 
> 
> --- "Denis Gökdag" <q-art@...> wrote:
> 
> > Hi List,
> > 
> > having another look at the quadrature LFO and the
> > cool looking companion quad VCA i stumbled upon one
> > feature that i miss in the current design of the
> > quadrature LFO: a reset/sync input for the
> > quadrature LFO. I believe that this is a simple yet
> > very important feature for such a module. I'll want
> > to use the module for creating sweeping FX sounds,
> > and these require a defined starting point of the
> > quadrature modulation. Also when using the module in
> > the audio range a sync in would greatly expand
> > possible results.
> > 
> > Another idea would be adding four switches to the
> > quad VCA that switch an inverter into the control
> > signal path of the the respective VCA; possibly
> > three-way switches that switch between normal, "x->
> > x*(-1)" and "x-> 5V-x" modes (where the first
> > inverter mode basically "mirrors" the control signal
> > around zero which would be most interesting for
> > processing control signals, and the second mode
> > would be more along the logic of a "crossfader" and
> > mainly interesting for processing audio signals).
> > 
> > Apart from these suggestions i am *very much*
> > looking forward to these modules as described on the
> > doepfer site :-)
> > -- 
> > Der GMX SmartSurfer hilft bis zu 70% Ihrer
> > Onlinekosten zu sparen! 
> > Ideal für Modem und ISDN:
> > http://www.gmx.net/de/go/smartsurfer
> > 
> 
> 
> Bakis Sirros - Parallel Worlds
> [Doepfer_a100] group owner
> http://www.parallel-worlds-music.com
> http://www.myspace.com/parallelworldsmusic
> http://www.shimarecords.co.uk
> http://www.rubber.gr
> Athens-Greece
> 
> 
>  
> 
_____________________________________________________________________
_______________
> Have a burning question?  
> Go to www.Answers.yahoo.com and get answers from real people who 
know.
>

Denis,

you find my comments written inline.

Best wishes
Dieter Doepfer

> having another look at the quadrature LFO and the cool looking
> companion quad VCA i stumbled upon one feature that i miss in the
> current design of the quadrature LFO: a reset/sync input for the
> quadrature LFO. I believe that this is a simple yet very
> important feature for such a module. I'll want to use the module
> for creating sweeping FX sounds, and these require a defined
> starting point of the quadrature modulation. Also when using the
> module in the audio range a sync in would greatly expand possible results.

We tried this but it did not work so far. The problem is caused by the main
circuit which is kind of filter in self resonance. If one resets the circuit
(simply by shortening to GND with a electronic switch or transistor) the
oscillation stops but comes little by little until the maximum level is
reached. This is not what you'd expect from a reset/sync function. I don't
know an analog circuit the generates sine/cosine ("quadrature") and can be
reset in the usual way (except digital solutions). Maybe somebody has an
idea.

> Another idea would be adding four switches to the quad VCA that
> switch an inverter into the control signal path of the the
> respective VCA; possibly three-way switches that switch between
> normal, "x-> x*(-1)" and "x-> 5V-x" modes (where the first
> inverter mode basically "mirrors" the control signal around zero
> which would be most interesting for processing control signals,
> and the second mode would be more along the logic of a
> "crossfader" and mainly interesting for processing audio signals).

In principle this would be possible but the existing quad VCA prototype has
only one common current source for all four VCAs (= four OTAs). Your
suggestion would require a separate current source for each VCA which comes
close to 4 separate VCAs (e.g. four A-130). The costly part of a VCA is just
the current source (not the OTA which is about 30-40% only). Consequently a
quad VCA with four completely separate VCAs (and separate controls) would
not be much cheaper than four separate VCAs.
An intermediate solution would be only two (opposite) current sources which
can be assigned to each VCA by switches (e.g. on - off - inverted).

And one has to distinguish between inverting the signal and the control.
These are two different things. Inverting the signal does not make much
sense from my point of view as the inverted signals are already available
(e.g. 180 degrees is nothinf but the inverted sine).

> I was playing around with the Oddity softsynth the other day and got
> thinking--I've got more than enough oscillators on my modular (4) to
> make some amazing duophonic sounds.
> 
> How would I go about this? I've got the basic Doepfer MIDI-CV
> converter and an M-Audio Axiom controller...obviously the problem
> would be figuring out how to assign each of the two voices. Can I do
> this with my current equipment?

You need the MCV24 or two A-190/MCV4 for this function.

Best wishes
Dieter Doepfer