Skip to main content

Topic: Duration error when using pitch bend (Read 2873 times) previous topic - next topic

Duration error when using pitch bend
At 3rd staff, the first 4th note sounds longer than the second.
NWC Viewer - the same.
When opened in other midi-related program, it sounds okay.
  • Last Edit: 2010-09-22 12:09 am by Yoon-ei Kim (Sesirine)
NWC User since 2008

Re: Duration error whan using pitch bend
Reply #1
This seems to be all to do with the pitch bend sweep resolution instruction.
If you change the sweep resolution to 700 it is hardly noticible.

The pitch bend appears to affect the third staff even when only the third staff is played (shift f5). But I suspect this is all to do with the rate that the pitch bend changes. There are possibly too many calculations to do when the sweep is set to 32 and so it can't be managed within the music time frame and so delays and then has to catch up. At 700, there are not as many calculations to do and so all can be achieved within the specified time.

However, I'm only guessing - My bet would be that Rick would know.

Not sure why it would be different in a different midi related prog but maybe the rates are not calculated in the same way or the graphics needed in NWC make the difference ???
  • Last Edit: 2010-09-21 03:17 pm by Richard Woodroffe
Rich.

Re: Duration error whan using pitch bend
Reply #2
It is a bug.
Registered user since 1996

Re: Duration error when using pitch bend
Reply #3
It is a bug.

Please elaborate...

Re: Duration error when using pitch bend
Reply #4
Please elaborate...
It helps to mute the 'Vocal' staff. If the pitch bend is changed to:
Quote
|MPC|Controller:pitch|Style:Linear Sweep|TimeRes:Sixteenth|SweepRes:32|Pt1:17,8192|Pt2:2,16383|Pt3:1,8192
the spurious tempo variation moves to the next measure.
It is a bug for a pitch bend to change tempo.

We now have 3 users on 3 continents using various hardware and windows versions reporting this.
It is not possible that all these sound cards throttle the throughput to the same baud rate as an external synth or it would affect playback from the generated MIDI.  Sesirine reports (and I confirm) that the MIDI that NWC generates plays back correctly.

If this were a decade ago and we were using a '486 I could understand a bit of delay to process the large number of events.
Registered user since 1996

Re: Duration error when using pitch bend
Reply #5
Fair points. The attached variation on Sesirine's file actually mutes the top staff and assigns it to a null play back device, and yet the play back delay persists. This issue will be reviewed.

Re: Duration error when using pitch bend
Reply #6
Thanks for the report. This problem will be solved in the next releases of NWC and the NWC Viewer.