Questions for synthesists with ribbon controllers

[Folderol]

[BJG145]

I'm currently looking into how it might be possible to play Yoshimi with a ribbon controller using this kind of technique...

https://youtu.be/9yJjmelle0I?t=11

That's the kind of thing I'm used to. It's usually also possible to get them to snap to scales, but that kind of defeats the object.

I've been able to recreate this with the Artiphon Instrument 1 and Rob Papen Blue on a PC. I can set the Artiphon pitchbend range to 24...



(...the max is 48, which is an MPE standard...)

...and I can match that with the same pitchbend range in Blue.



(I can't see an obvious way to get that above 24; maybe there's a newer version out now, but quite a lot of older VSTs have restricted pitchbend ranges as there probably didn't seem any need for super-wide ones at the time.)

I can then tap the Artiphon's fretboard at different places to play a note, and also drag notes around in a legato way; eg I can tap three frets lower, or drag three frets lower to glide down, ribbon-synth style. Tapping gives you note-on/note-off, while dragging is implemented via that wide pitchbend setting. I think this is a pretty standard approach for MIDI-capable ribbon controllers.

I can tap different notes in Yoshimi, but I can only drag up and down up to maybe a couple of semitones along the whole length of the fretboard. In order to play it ribbon-style via the Artiphon (or some other ribbon controller like the Eowave Persephone), I'd need to be able to set the pitchbend on Yoshimi to 24, or 48, say. At the moment I'm not sure how to change it, or whether I can. Is it fixed at a maximum of a semitone up and down, or is there an option to set it somewhere...?

(Using a ribbon controller for expression is a different matter, as that's based on MIDI #CCs and pitchbend isn't. I'll look at that too.)

[Folderol]

You can expand Yoshimi's pitch bend range in the Controllers window. It's right in the middle at the top! Go too far and it starts to go in steps. This is partly dependent on the control source and partly the NRPN resolution - a lot of pitch wheels only have about 10 bit resolution.

P.S. we should probably try to find some way to interpolate intermediate values from a moving control.

[BJG145]

...right, gotcha. That's in cents, so to match the 24 I set on the Artiphon it needs to be 2400...which then works in just the same way as Blue. Here's a quick demo. I've tacked on some dodgy Artiphon/Yoshimi guitar strumming as a bonus.

https://youtu.be/pSMEIjNfVv8

*************************

Incidentally I re-read the notes where you were describing how portamento might be used instead...

...set Mode to Legato and just below that set the Portamento checkbox. Next, click on Controllers, and in its window change Portamento Thresh to 0 and Time to about 80. The ribbon should now give you a smooth sweep...

...but, for reference, there's a few complications.

1) If you're gliding to note values instead of using pitchbend, you're only going to get exact notes. Part of the appeal of ribbon controllers is being able to play out of tune...or, let's say, play notes slightly sharp or flat like a violin. You can play vibrato by wiggling a finger. They're not enslaved by equal temperament or any of that stuff; you can play microtonal scales if you choose.

2) You'd need to be able to configure the ribbon controller to send a string of note-ons when dragging from one note to another, rather than sending pitchbend. The Artiphon can do either, but I'm not sure how common that is.

3) You can control 'glide time' in real time on a ribbon controller; fast, slow, variable. I'm not sure how well that would fit with the glide time that's usually associated with portamento controls. I'm not able to test that thoroughly with the Artiphon, because it transmits a string of note-on/note-off as you drag up the fretboard in "send notes" mode, producing a chromatic scale instead of a sweep. In order to use a ribbon with a typical portamento setup, where you hold the start note before pressing the end note, I think you'd need to be able to configure the controller to send a string of only note-ons as you drag, and a set of note-offs when you release, which would get a bit complicated.

...so...yeah, I reckon pitch control via a ribbon controller needs a wide pitchbend approach rather than trying to piggy-back on portamento. Most Windows VSTs tend to follow the approach of Blue illustrated above, with separate bend-up and bend-down response values that can be set to anything you like, counting in semitones, with a maximum of at least 48 for MPE support. But as I say, the control you've provided works fine for me.

[BJG145]

...just one more thought, which is that the Artiphon has this rubber fretboard thing going on, where it doesn't feel natural or comfortable to have more than a semitone per fret. But normal ribbon controllers don't, and can cover several octaves over the same length. I think the Continuumini covers a couple of octaves within its 50cm or so, while the Persephone has a scale control with increments that go up to several octaves IIRC. When I've finished "Morse Machine" (patent pending) I'll be able to do some more testing and see how far I can ramp up Yoshimi's pitchbend setting.

[Folderol]

Very pleased with the results you got
I take your points about using separate notes with portamento. It wouldn't really work except in very specific cases.

[BJG145]

Resistors galore...600 for £3.95.



The FSR strip will take a bit longer to arrive as it's coming from China, but I think I've got everything to mock up a basic ribbon now....

[Martin Walker]

I think you ought to start a DIY channel Ben - your posts are invariably fascinating, most creative, as well as educational

[Folderol]

Resistors galore...600 for £3.95.

Are they all the same value?
I was given a large bag of 39k 5% resistors in the late 1960s. I still have one or two

[BJG145]

I've been tinkering around with some designs, and I think I'll go for something Persephone-like.



Talking about it is one thing though, building it is another. DIY was never my strong suit, but I'm hoping the tech at the Hackspace might help me put it together. First induction session on Monday. So...we'll see. (Thanks for the encouragement!)

[Folderol]

Is your ribbon three wire or two wire? i.e. potentiometer or rheostat.
If the latter, you need to feed it from a constant current source, not a resistor. Otherwise you'll get a non-linear result, and pitch bend uses a linear input which is then converted to log by the synth.

[BJG145]

It's three wire...or it was.

Soldering remains a mystery to me. You wouldn't have thought it would be difficult to attach three wires to three pins with a roll of solder, a tin of flux, a fine-tipped soldering iron and a magnifying glass, but the stuff just won't behave for me. It just doesn't stick to the pins. So I did my usual thing of cursing over it for five minutes until two of them eventually broke off.

I think you ought to start a DIY channel Ben

It would have to be a comedy programme.

This iron is clearly too hot. I'll save what's left of the ribbon for the Hackspace.



(I think the old fluxed solder I was using was probably the main problem; it kept crumbling away. Apparently this happens if it gets humid.)

[Folderol]

Ouch. Get yourself a reel of multicore solder and throw what you've got away.

The situation is recoverable - just.
Iit looks like you used solid core wire - get rid of that too. You want very fine mulitcore flex. I cut up an old Centronics printer cable for this sort of thing - it's perfect
You won't be able to solder to the resistor element itself but there is enough of the tab left to make friction contacts. For this I would make a tiny clamp out of a couple bits of insulating board (paxolin) with something like M2 holes just beyond the width of the tape, then carefully scrape way the insulation from one side of the tape, lay this on one clamp piece insulated side down with a tiny dab of glue. Lay the bared wires on the strip and the other clamp piece on top, and bolt it together. Very fiddly, but I've done similar before.

[BJG145]

...right, thanks for that. I wasn't optimistic about being able to solder wires directly to the traces, so clamping sounds like a better idea.

[BJG145]

These people at the local Hackspace are going to be handy to know. They use a Slack workspace. I just posted up some thoughts wondering how to assemble that Persephone-esque shape out of laser cut parts, and less than half an hour later someone had modelled it as a laser design using OnShape, and posted up a link to the files.

[Martin Walker]

Wow - your local Hackspace is being extremely helpful Ben!

[Folderol]

Wow - your local Hackspace is being extremely helpful Ben!

They are indeed!

[BJG145]

After pondering this knackered sensor for a couple of days, I've decided to abandon it and get another one. I've been reading about soldering these things, and in fairness they do seem like delicate creatures - especially the FSRs; good job I read about that before it turned up.

I hadn't realised that the pins on the sensor are designed to be plugged directly into a breadboard. I just want to get on with the Arduino testing stage without extra complications, so, I've ordered a replacement...and a breadboard.

[Folderol]

Psst!
Want some 60/40 solder

[BJG145]

I'm done with soldering for now. I've got a pack of crocodile clips.

I'll probably use these 'Amphenol CFI clincher connectors' for the final version, based on the clamp principle.