Pitch CV as a v-trigger sync signal

For no real reason  I occasionally consider using CV for other purposes, todays goal is to use pitch CV to emulate a V-Trigger pulse clock signal.

If V-Trigger uses a voltage transition between 0V and 5V.

While Oxi One sequencer using V/Oct CV range, 0V is C2, 5V is C7.

> Sequence a simple pitch sequence between those two  notes.

Select a mono track on the Oxi One,
set CV settings for track to ouput pitch v/oct,
connect cable between CV out on Oxi and SYNC in on device.

Oxi One - Setting the CV out as V/Oct, and using the Major scale for simplicity.
Other devices - using 1 PPS for simplicity.

This of course worked*, so I decided to go a bit further and explore workable pitch ranges for the transition to work.

If C2 - C7 works, would C3 - G4 work?
What range of pitches would satisfy required levels for triggering?

This was done by modifying the simple melodic sequence (C2, C7) to discover the transition pitch between the sync working/not working.

Raise the lower pitch until it stops working, lower to working pitch
Lower the upper pitch until it stops working, raise to working pitch
**Confirm lower pitch,
Reset lower pitch to C2, confirm upper pitch.

Table shows working ranges,
pitches below the down column, and above the up column.

I found two types of responses.
The first responds when the pulse changes around a central value - the values below show the smallest difference that would work.
The second responds to a change of a certain value but with no fixed centre - the values below show the smallest difference at either extreme.

                                                range in pitch,              

Arturia Beatstep Pro                C3/B3

Behringer TD3                        C3/D4

Behringer RD8                        C3/A3

Behringer Crave                      A3/B3           

Roland TR-06                         A2/B2

Second Type 

Korg Monotribe                     C-1/D-1    and     A6/B6

Sonicware XFM                     C-1/E-1    and      G6/B6

*With caveats for timing, 1PPS was the simplest to work with.
The end device tempo of is based on the Oxi sequencer timing and any device scaling settings. Sequencer settings also determine pitch at 0V.

**Added the confirm step to allow for devices such as the Sonicware XFM which does not have set pitch points, any interval of at least 4 semitones seems to work.

3x Behringer Neutrons - what do I do with them?

So I figured I need to explore modular synthesis a little.

Buy 24 eurorack modules? or buy 3x Behringer Neutrons?

I followed the second path and am now trying to expand my knowledge ...

EXPLORATIONS

After some thinking about the sound ideas outlined further below makes me aware of how i dont understand the relative voltages,
LFO             -5v to 5v
LFO UNI      0v to 5v
ENV              0v to 9v

VCA CV        -9v to 9v
ATT1 CV        -5v to 5v

_+_+_+_
Patch test, compare the LFO outputs vs the ENV outputs on the VCA CV, and the ATT1 CV.

How does the LFO work as a VCA modulator?

How does a slow square LFO against constant ENV values compare on OSC pitch

Ideas.

Slew as a third envelope - ASR
TRIGGER > SLEW IN . SLEW OUT > ATT 1 CV 

SLEW rate for attack/decay time, or via ATT2 for height.

ENV out            0V to 9V
SLEW out           -9.5V to 9.5V
ATT1 CV in    voltage range -5V to 5V . excess V will be truncated.

Multiple Stages by using Pitch - constant AR time.

BSP pitch out          0V to 10V
Neutron Pitch out     0V to 5V

each OSC with their own ENV 

OSC1 > VCA
ENV1 preconfigured
VCA > ATT2 for volume reduction?
ATT2 > SUM1

OSC2 > ATT1 IN
ENV2 > ATT1 CV
ATT1 > SUM1

SUM1 > VCF
VCF is output
VCF > DELAY IN

problem with ENV2 output 0 to 9V, ATT1 CV input -5 to 5V. so VCA needs to be attenuated? or how to gain ATT1?

how about using pitch to generate 5V, first add the inverted to the envelope to move into range -5V to 4V, then add 5V to ATT1 .. oh wait, that would truncate the OSC output in the negative range ..

LFO to mix between OSC - imagining CV input to the OSC MIX knob

1) use LFO on VCA for OSC1 and inverted LFO on ATT1 for OSC2 - no GATE envelope? maybe use env2 on filter?
....
OSC1 > VCA
OSC2 > ATT1
LFO UNI > MULT

MULT1 > VCA CV
MULT2 > INVERT >ATT1 CV

VCA > ATT2
ATT1 + ATT2 > SUM1
SUM1 > VCF IN
VCF1 is output, run through DELAY to get main output.

again ATT1 range will be half so, something needs to go through ATT2, could be OSC1, or ENV1, or VCA

2) or can I phase invert for silence? invert OSC MIX then run through ATT1 and sum with OSC1

OSC MIX > INVERT
INVERT > ATT1 IN
LFO  > ATT1 CV

OSC 1 + ATT1 > SUM1
SUM1 > VCF

.. if 2 works, then could also use ENV2 to control the mix

PLOGUE FUN

I got inspired to try a couple of things in plogue. These are more in the line of signal processing rather than composing_ but they do give rise to dramatic results !!!

My first idea was to break an incoming audio signal up into dynamic ranges, for each cycle that is. So different sections of the same cycle can be routed differently :)
I have really only tried this with bit and sample rate modification.



It does work well though !! Interesting results with sample rate, a lower rate for the lower thresholds, moving up to a higher rate for the higher..


The next, was to replicate a complex wave with a sine wave :)
The idea was to use zero crossings as points to determine the freq of the sine wave. This itself has been not particularly succesful - this may because Plogue does not do good maths :(

the idea is, when the wave crosses zero, the accum will split out the length of samples since last crossing - this gets converted into the freq of the lower oscillator.
The delay line is to make sure the freq's exist for appropriate lengths - this bit is wrong - needs more work !!

The next part of this one, is to get some sort of average amplitude for individual cycles.

modular synthesis

synth edit is a Modular Synthesiser for Windows.
it has a shareware version, with more featurables if you register $50US..
http://www.synthedit.com/

and once you've done you're work.. you can export them as VST's. this program accounts for a number of VST download pages out there...

eg http://rekkerd.org/dsk-vsti

Plogue Bidule is another modular synthesiser.
it has a time limited free version.
We are using this at University so I've been enjoying it - and will be using it to control a suite of feedback devices in a few days...
http://www.plogue.com/