Sound leakage (SOLVED)

[witti]

Just discovered this:

When having two tracks with identical media files and one track is phase inverted and the other track has an fx inserted, on playback stop there is some sound leakage.


-insert two tracks
-add the same media file to both tracks
-insert any fx (e.g. reaeq, with no special settings) on track 1
-phase invert track 2
-start playback
-stop playback (sound is coming through)


Reaper 4.721 32bit
winXP

[Fergler]

Originally Posted by witti

When having two tracks with identical media files and one track is phase inverted and the other track has an fx inserted, on playback stop there is some sound leakage.

This is due to plugin delay compensation. The track with no effects is stopped more quickly, thus destroying the null from the polarity inversion (not phase inversion if you don't learn now you never will and then it will spread even more)

[witti]

(Yeah, it's polarity, not phase.)

PDC ? Tested it only with plugins which are not introducing any latency.
And even if they introduce some, reaper should compensate for that, if reported correctly to the host.

Still have to test it, but i'm 99.9% sure that this behavior didn't happen in earlier versions...

[Dstruct]

Originally Posted by witti

Just discovered this:

When having two tracks with identical media files and one track is phase inverted and the other track has an fx inserted, on playback stop there is some sound leakage.


-insert two tracks
-add the same media file to both tracks
-insert any fx (e.g. reaeq, with no special settings) on track 1
-phase invert track 2
-start playback
-stop playback (sound is coming through)


Reaper 4.721 32bit
winXP

Confirmed.

Happens if "Run FX when stopped" (Preferences: Audio/Playback) is disabled or "Flush FX on stop" is disabled ("Run FX when stopped" enabled).

[musicbynumbers]

I'm not getting that here with either of those settings on or off, even if "run fx for.." is set to something other than "0".

thought it might be feedback routing which I have off normally but that didn't change anything either.

I only tried with ReaEq though.

Could it be a sound card issue? I'm on the latest reaper (pre) so maybe they fixed it and it was a temp bug?

[Dstruct]

"Anticipative FX processing" needs to be enabled to reproduce!



Put into bug tracker: http://forum.cockos.com/project.php?issueid=5333

[witti]

Thanks dstruct ! Was quite busy lately, so had no time to investigate further.

[ELP]

This is the render ahead buffer.

With "Allow on tracks without FX" enable, or both Run FX and Flush FX on stop enable it does not happen. Or with Run Fx for ms=0 after stop.

But after pressing the "Stop button", you can hear the full render ahead buffer. Confirmed
Whether with "Run FX on stop" enable or disable does not matter if ms > 0.

You can enable Run FX and Flush FX on stop
Or Allow on tracks without FX
Or without Run FX ms=0
Otherwise you hear the FX ahead buffer(after pressing the Stop button)

I think this is maybee not really a bug and
it happen in older Version like 4.62 or offiziell 4.721 and in the new betas

[Ollie]

ELP is correct, it's the render-ahead buffer. In other words tracks with FX simply don't stop playing at the same time as tracks without FX when you hit stop in mid-project. It's not that they're not nulling anymore, it's that there's nothing to null with anymore for the render-ahead time after stop.

This is just how REAPER works, pretty much everything's reaction is determined by the render-ahead time. If it bothers you that tracks without FX are not affected by render-ahead, enable "Allow on thracks without FX..." in the same Preferences section.

[witti]

Thanks, ollie ! Sometimes reaper has too many options....