[Ardour-Users] Aligning recording with existing material

[Per Sigmond]

On Monday 25 October 2010 18:51:13 Per Sigmond wrote:
> On Monday 25 October 2010 14:41:58 Paul Davis wrote:
> > On Sun, Oct 24, 2010 at 7:51 PM, Per Sigmond <per at sigmond.no> wrote:
> > > I have RME and the setting is "Audio hardware does minitoring".
> > > 
> > > As I just said in a posting (sent 5 seconds before your answer came in)
> > > I found after some more testing that ardour 2.8.6 actually works
> > > perfectly while 2.8.9 (and later) is misaligned.
> > 
> > the monitoring setting is actually irrelevant.
> > 
> > there have been a few reports of this issue over the last couple of
> > months. i'd like to put some time into it, particularly because you've
> > established that 2.8.6 works presumably with *exactly* the same set of
> > steps. Its a bit tricky because of other committments right now, and
> > the fact that in the past whenever I dig into this it turns out to be
> > user error. In this case, I suspect its not that. There were some
> > commits that specifically affected this stuff between 2.8.6 and 2.8.11
> > and so in theory it should just be some triangulation of which ones
> > caused the breakage. However, those changes were done for real
> > reasons, so it will then be necessary to reconcile when they work
> > versus when they break ...
> > 
> > --p
> 
> Thanks, Paul. To give you a starting point I have attached a modified part
> of audio_diskstream.cc from 2.8.11 that actually seems to fix my problems.
> It seems to work even for punch in/out. The changes are based on looking
> at 2.8.6 and pure luck :-). It may break something else, but it works for
> me.
> 
> /Per.

A related question: I had the impression that there is no latency compensation 
on buses? If that is the case, I cannot understand why inserting jconvolver 
(reverb) in a bus makes my recording misaligned. To my mind it should be the 
same (the reverb would be delayed, but that wouldn't bother me too much). 
Deactivating the insert makes eveything fine again. Also, inserting an 
artificial delay (of the right amount) in the track I record makes the 
recording aligned. Does this make sense?

/Per.


-- 
Per Sigmond
Gjert Sorensensvei 5
4879 Grimstad
Norway
+47-90721913
per at sigmond.no
http://www.sigmond.no/per