Strange portamento behaviour

[Ortseam]

This picture shows pressed MIDI keys and Karma's OSC frequency graph sharing the same time scale.

At the left side of the picture the one can see nice analog-like curve which you could expect from a real synth. If there's enough tіme for frequency to reach the new note value it behaves absolutely okay.

But when the new note changes earlier than the frequency fіnishes the portamento movement the one can see (and hear) the sudden jump to the frequency of just released note. The next portamento starts from this new point as shown at the right side of the picture.

I find this a bit frustrating. It's not what you'd expect from analog synth, which produces continual tone change without jumps in portamento mode.



Could you please clarify what was the reason behind that or it can be considered as some kind of imperfection?

Thank you! Sorry for being so nagging. Maybe I'm a perfectionist...

[Ortseam]

That's how other instrument acts with the same MIDI:

I think it's more natural. New portamento always starts from the point where previous portamento stopped.

[karmafx]

Sounds like a bug to be honest. So don't feel bad btw.. Please keep "nagging"
The portamento works differently in mono vs poly modes. However, that said, it should not reset on release. That just sounds wrong.
If this happens on any patch I will look into it, otherwise please send me the repro steps.

[Ortseam]

Seems it happens at any patch but I'll check it out tomorrow. In any case I'll come back with the result.

[karmafx]

Great! Thanks!!
EDIT: Meanwhile I will try to repro too.

[Ortseam]

Seems it's a global portamento problem. It's present an mono and legato modes, fixed and auto, linear and range-scaled.

[karmafx]

Yeah..I've reproed the bug.
Also found the offending line in the code.
So looks like this fix will be in v1.20.
That code was pretty old. So I'm surprised that this has gone unnoticed for so long.
The code was unique for mono/legato modes. So just to be sure, you did not encounter this issue in poly(phonic) modes, right?

I will need to test it some more though. If you would like a v1.20 beta, just let me know.

[Ortseam]

That's so nice that my report helped!

you did not encounter this issue in poly(phonic) modes, right?

I've never used portamento at poly mode, but I'll try today
UPD: tried it. Though I don't understand completely the logic of portamento behaviour in poly mode, I can safely say that there's no tone 'jumps' at note releases.

If you would like a v1.20 beta, just let me know.

I would be so much pleased to help Karma as beta tester. Feel free to send me your betas any time the testing is needed.

[karmafx]

Cool! I will get you a beta.

[Ortseam]

Great! Thank you!

[karmafx]