An interesting glitch in using only one channel

Started by FreezeFlame(Alchemy), November 01, 2014, 20:22:17

Previous topic - Next topic

FreezeFlame(Alchemy)

I don't know why, but if only one channel is in use, then it will cancel the note at row 15,31,47,63 in OpenMPT (in XMPlay, it cancels it out in row 31 and 63).

I made an test module to demostrate this 'voice cancel'.
In pattern 0, only one channel is in use (demontrating the little glitch).
But in pattern 1, another voice is included and the glitch dissapears (until you cancel out the sample/s being played on it).

Not an really important glitch, but worth mentioning.
Blue Flames of the Night.

Was known as Alchemy before(with an Dialga picture).

Saga Musix

#1
QuoteNot an really important glitch, but worth mentioning.
Every playback bug is a bug worth mentioning, but I have no idea what you are talking about here. I hear all notes being played, so where's the bug supposed to be?
Channels never "talk" to each other on the code level in OpenMPT, so if there is something that sounds different if two channels are playing compared to one channel, it must be in the nature of the samples (e.g. phase cancellation) and no the code itself.
» No support, bug reports, feature requests via private messages - they will not be answered. Use the forums and the issue tracker so that everyone can benefit from your post.

FreezeFlame(Alchemy)

QuoteI hear all notes being played, so where's the bug supposed to be?
How can this be? It plays broke in XMPlay and OpenMPT 1.23.05.00.
But if its not to much to ask, does it not cancel the note at row 15,31,47,63 in you're current OpenMPT build?

But if it helps at all, i uploaded an OGG Vorbis file which shows, how the playback works on 1.23.05.00 on my PC on pattern 0.
Blue Flames of the Night.

Was known as Alchemy before(with an Dialga picture).

Saga Musix

Uhm, the OGG file just proves once more that every note is playing as expected? There's not a single second of silence in there. Do you need a picture to prove it?
Maybe acoustics are just playing a trick on you and your brain filters out notes that are actually there.
» No support, bug reports, feature requests via private messages - they will not be answered. Use the forums and the issue tracker so that everyone can benefit from your post.

FreezeFlame(Alchemy)

I think it is this phase cancellation that is causing this problem.
I have cut the part that cancels the note at row 15. Have a look at it yourself.
And i have checked the waveform (in stereo), thank you.
Blue Flames of the Night.

Was known as Alchemy before(with an Dialga picture).

Saga Musix

Err. I still don't get the point you are trying to make. Assuming that the content of that wav file is supposed to be row 15 and 16, then what is wrong with it?! It's a G-5 playing at half volume, and C-4 at quarter volume. No missing notes to be seen anywhere.
Besides, phase cancellation was an example of what could be happening with two samples playing at once. You cannot have phase cancellation with just one sample (unless it's of course part of that sample).
» No support, bug reports, feature requests via private messages - they will not be answered. Use the forums and the issue tracker so that everyone can benefit from your post.

FreezeFlame(Alchemy)

QuoteI still don't get the point you are trying to make. Assuming that the content of that wav file is supposed to be row 15 and 16, then what is wrong with it?!
That there is no sound to be heard. The waveform i uploaded captures how it goes from F5 at full volumen to G5 at half volumen and G5 gets quickly cancels out.
Blue Flames of the Night.

Was known as Alchemy before(with an Dialga picture).

Saga Musix

Yes, the sample's waveform actually decays to about half volume. Just zoom into it and look at it. So, nothing wrong.
» No support, bug reports, feature requests via private messages - they will not be answered. Use the forums and the issue tracker so that everyone can benefit from your post.

FreezeFlame(Alchemy)

I found the issue.
I tried to create an panbrello effect, which caused that G5 at row 15 gets quicly cancels out (in XMPlay, its in row 31).
But after i removed the S8x commands from the effect column, it works flawless.
Blue Flames of the Night.

Was known as Alchemy before(with an Dialga picture).

Saga Musix

...so you were only talking about the left channel in that example? Isn't it quite, err, logical that when you pan a note hard-right (S8F), it won't be heard on the left channel at all?
» No support, bug reports, feature requests via private messages - they will not be answered. Use the forums and the issue tracker so that everyone can benefit from your post.

FreezeFlame(Alchemy)

Quote...so you were only talking about the left channel in that example? Isn't it quite, err, logical that when you pan a note hard-right (S8F), it won't be heard on the left channel at all?
'sign'.
I think that this S8x command is the problem. I have replaced the supersaw with the snare and only leaved s8x commands on row 15,32,47,63 and it freaking cancels not only one note of an row, but everything on that channel until it gets to the next s8x command (in OpenMPT 1.23.05.00).
Blue Flames of the Night.

Was known as Alchemy before(with an Dialga picture).

Saga Musix

Okay, may I suggest you to check if your speakers are set up correctly? In any version of OpenMPT I've tried (OpenMPT 1.23 stable and 1.24 testing), this behaves as expected - 16 centered hits, 16 hits on the far right, 16 hits on the far left and then 16 hits on the far right again. If by "cancelling" you mean that you don't hear anything at all anymore, maybe one of your speakers is dead or are not wired up properly? :P
» No support, bug reports, feature requests via private messages - they will not be answered. Use the forums and the issue tracker so that everyone can benefit from your post.

FreezeFlame(Alchemy)

I do admit that i have an surround setup and could only wire one set (front or rear).
I'll redo my setup later.
Blue Flames of the Night.

Was known as Alchemy before(with an Dialga picture).

FreezeFlame(Alchemy)

I have tried it also on my old Netbook... and it worked without those nasty cancels.
Atleast i know that my surround set needs to be rewired.
Blue Flames of the Night.

Was known as Alchemy before(with an Dialga picture).