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Pro 3 - Appendix X: Additional Technical Details, Lookup Charts, Notes

I'm starting this thread to be an unofficial repository of additional technical details and notes about the operation of the Pro 3...  stuff that is not covered in the manual. 

Lookup Charts, Reference Materials, Technical Notes, Obscure but Important Tricks.  etc...

First up:

OSCILLATOR TUNING LOOKUP TABLE
Below is a Lookup Table for modulating the Oscillator Frequency from the Pro 3 Mod Matrix, LFOs, or Gated Sequencer.   You can use this reference to quickly lookup common musical intervals and set them precisely for modulation.  The values from the Mod Matrix and LFO are same in this unit, however, when routing from the sequencer, the resulution/scaling is different. 

Osc Course Frequency Modulation:
For Osc Course Frequency, from the Matrix/LFO, each value tick is equivalent to 50 cents.   In the sequencer, each value tick is equivalent to about 12.5 cents for course frequency modulation.

Osc Fine Frequency Modulation:
For Osc Fine Frequency, from the Matrix/LFO, each value tick is equivalent to about 5.4 cents.   In the sequencer, each value tick is equivalent to about 1.3 cents for fine frequency modulation.



Note:   All of the LFOs are unipolar (they generate positive values only), EXCEPT FOR the Triangle, which is bipolar - it swings to both positive and negative values.   In the current version of the manual, it states the Sample/Hold Random LFO is bipolar too, but I think that might be a misprint, based on my testing?... seems to be unipolar.     So, if you're modulating OSC FREQ with the triangle, you may want to double the values listed above, if you want the frequency to swing the full interval in both directions... otherwise it will swing half positive, half negative.   

Sequential Pro 3 and Rev 2 - Sound Sets, Patch Banks - Available on Sellfy: https://sellfy.com/sounddesign/  HOLIDAY SALE $10off

Recursive Envelope Modulation
Here is an article describing Recursive Envelope Modulation with the Sequential Pro 3:

https://www.presetpatch.com/article/Recursive-Envelope-Modulation-on-Synthesizers

Recursive modulation can be used to adjust the contours/shapes of the envelope stages.   You can get a snappier attack to match the envelope performance of other classic synths or for more percussive type sounds.

Or alternatively, you can achieve a more gradual, linear type of swell than the standard envelope shape - which can be useful for slowly evolving pad type of sounds.

Some examples from the article: 







Sequential Pro 3 and Rev 2 - Sound Sets, Patch Banks - Available on Sellfy: https://sellfy.com/sounddesign/  HOLIDAY SALE $10off


Nice

Iíll add notes from Sequential regarding CV as itís unclear and thereís a typo in the manual:


The range for the CV outputs is -10V to +10V. There are offsets available in the Globals menu for each of the 4 CV outs, which allow you to tweak a few volts in either direction. There are also globals for Scale for each CV out. The Offset and Scale adjustments are useful for fine tuning V/Oct accuracy, and are typically set once and then left alone.

The CV inputs are scaled to work best with +/-5V signals. There is protection for higher voltages, but you won't get much usable range with larger signals. There are also Offset and Scale adjustments in the globals for the 4 CV ins.

The Gate Out provides a +10V signal, and follows the keyboard and/or track 1 of the sequencer.

I'm starting this thread to be an unofficial repository of additional technical details and notes about the operation of the Pro 3...  stuff that is not covered in the manual. 

Lookup Charts, Reference Materials, Technical Notes, Obscure but Important Tricks.  etc...


Many thanks for taking the time to research and post this. - very useful.
 :)
Pro-3, Rev2(16), Prophet 6, Subsequent 37, Behringer Odyssey, Behringer Neutron

Recursive modulation can be used to adjust the contours/shapes of the envelope stages.   You can get a snappier attack to match the envelope performance of other classic synths or for more percussive type sounds.


Very interesting thanks a lot!

Re: Pro 3 - Appendix X: Additional Technical Details, Lookup Charts, Notes
« Reply #5 on: November 09, 2020, 04:07:34 PM »
Mentioned this in another thread, but adding it here as well, as its good tech reference:

Optimal Settings for Self Oscillating Filter Key Tracking:
This will give you a good range of octaves for filter key tracking.

1. Calibrate Oscillators / Filters
Turn down all three osc levels to 0

2. Use 4-Pole Prophet OTA Filter
The Prophet filter gets best results

3. Cutoff: 606
606 seems to works best for standard octave range
Nominal Values:
+/- 96 = 1 Octave up/down
510, 606, 702, 798

4. Resonance: 221
You get self oscillation in this range.... if you max out the resonance beyond this amount, the tracking is not as good.  221 seems to be sweet spot, at least on my unit.

5. KEY > LPF FREQ: +127   
This sets the key tracking to a nominal 1 semitone per key.

6. Mod Matrix: Note Num > Cutoff, Amount 1
This effectively turns KEY > LPF FREQ amount to +128.   
Note:  This may not be required on some peoples units... so ignore it if steps 1-5 give you better tracking.  Performance varies slightly between units... but for mine, I've found I get the best tracking results by adding this extra +1 to Key > LPF.   

Sequential Pro 3 and Rev 2 - Sound Sets, Patch Banks - Available on Sellfy: https://sellfy.com/sounddesign/  HOLIDAY SALE $10off

Re: Pro 3 - Appendix X: Additional Technical Details, Lookup Charts, Notes
« Reply #6 on: November 12, 2020, 03:12:49 AM »
Fantastic information, thank you 👍

Re: Pro 3 - Appendix X: Additional Technical Details, Lookup Charts, Notes
« Reply #7 on: November 18, 2020, 07:51:53 PM »
Addendum to Earlier Documentation of Self Resonant Filter Tracking

Note Number Modulation is scaled from the note G0, whereas Filter Key Tracking is scaled from C3.

A modulation of: Note Number > Cutoff, with value 122 gives you very close to 1 semitone per key (ie: 1:1 filter tracking)   If you set Cutoff to 268, that will set the keys in tune (depending on calibration).    Over a four octave range I'm getting within +/- 3 cents nominal frequency.  That's actually very good accuracy for analog filter tracking over a four octave range.

In comparison with just using Filter Tracking at full value (127), I'm seeing +/- 23 cents from over that same octave range / frequency range.

So, for most accurate performance, the former method actually seems to be the best... skip Filter Tracking altogether and instead opt for a mod slot with NoteNum>Cutoff at 122.   Note:   In most sound design scenarios this is not needed... but if you really need super accurate semitone-per-key tracking, this seems to provide best results.   (at least on my board... results may vary slightly board to board)

Sequential Pro 3 and Rev 2 - Sound Sets, Patch Banks - Available on Sellfy: https://sellfy.com/sounddesign/  HOLIDAY SALE $10off