Two Octave pitch bend introduces a second out of tune note

5 Jun 2014, 20:01

Hello, I am having a rotten issue with pitch bend. Using patch preset 831 Wide Syn Brs, when I set my pitch bend to 24 to get a 2 octave bend and using the first or second G key. When I bend the single not up the full 2 octaves I get a second ghost note that sounds along with my G key. Actually the Gkey bends out of tune flat and also introduces what sounds like an F. Of course this totally messes up what I am trying to acheive using a full chord. I have tried some other patches with the same result. Can someone try this and verify if you are getting the same thing. Thanks

james

Re: Two Octave pitch bend introduces a second out of tune no

7 Jun 2014, 01:53

James

I'm not sure I am getting the exact same thing you are, but there is certainly something amiss here. I selected 831 Wide SynBrs and set the bend range to 24. When I play the G above Middle C (we'll call it "Middle G") and bend down 24, I get a tone exactly two octaves below "Middle G", but when I bend up 24, I get a tone that is actually a few cents below two octaves above "Middle G". My first thought was a calibration problem with the pitch bend lever, but that would affect all notes. Whatever this is, it only affects the "G's". All other notes bend exactly as they should. Of course, if I did an up bend on any chord with a G in it, there was a very noticeable dissonance. This could be a sound engine hardware design problem or a firmware problem. At the moment, I can not think of any workaround for it.

Regards,

Ted

Re: Two Octave pitch bend introduces a second out of tune no

8 Jun 2014, 13:01

Would you know who we can report this to ?

Re: Two Octave pitch bend introduces a second out of tune no

8 Jun 2014, 14:55

James

Go to this page and send an email to Roland Support:

http://www.rolandus.com/support/email_support/

They are usually pretty good about getting back to you within 24 hours.

You send one and I will send one. That way we are sure to get their attention.

Regards,

Ted

Re: Two Octave pitch bend introduces a second out of tune no

8 Jun 2014, 17:02

Unfortunately, this is a design limitation of sample-based synths. There is a limit as to how far you can pitch up a sample.

I tested this with the similarly named "945 Wide SynBrss" on my Fantom-G. This Patch uses two waveforms: "Unison Saw A" which is panned left, and "Super Saw A" which is panned right.

Duplicating Ted's test with "Middle G" (G4) on the FG yields the following:

Unison Saw A G4 bends to F#6
Super Saw A G4 bends to G6

Both exhibit horrible aliasing at the upper pitches. Super Saw A reaches the expected pitch, but I would be reluctant to use it because of its aliasing.

And testing with G3:

Unison Saw A G3 bends to C#5
Super Saw A G3 bends to E5

This is one the reasons why people prefer analog or "real" virtual analog synths to sample-based ones.

Re: Two Octave pitch bend introduces a second out of tune no

8 Jun 2014, 18:27

I don't know much about the Juno-Gi, but here is a quick-and-dirty workaround you might be able to try.

Set Octave Shift to +1. This plays a sample that is an octave "too high."

Set the Pitch Envelope Depth to -12 and all of the Pitch Envelope Levels to +63. This "pre-bends" the sample down an octave.

Because the sample is already bent down an octave (by the Pitch Envelope), when you bend it up two octaves (with the lever) you are really only bending the sample one octave higher.

This workaround will change the tone quality of the sound.