4 Sep
2014
4 Sep
'14
11:34 p.m.
On Thu, 2014-09-04 at 22:05 +0100, Rui Nuno Capela wrote:
On 09/04/2014 09:33 PM, Ralf Mardorf wrote:
This year You record an audio track with an I+O latency of 10.7 ms.
Two year later you want to restore this session, but you don't remember
the jackd settings you used. Originally audio and MIDI tracks were in
sync, when you used 10.7 ms I+O latency. Within the years you got new
hardware, you don't remember what latency you once used and starts jackd
with a lower I+O latency. Nothing bad would happen for Ardour users, but
a Qtractor user would run into sync issues. Am I mistaken?
-------- Forwarded Message --------From: Ralf
Mardorf
<ralf.mardorf(a)rocketmail.com>
To: qtractor-devel(a)lists.sourceforge.net
Subject: Re: [Qtractor-devel] ; ) Was - Re: [LAU] Session management
with NSM
Date: Thu, 04 Sep 2014 22:31:15 +0200
Mailer: Evolution 3.12.5
On Thu, 2014-09-04 at 21:27 +0100, Rui Nuno Capela wrote:
and why would that be interesting?
qtractor does its "recording/input latency compensation" of audio cľips
*at the time* the audio material is captured, so that material gets
aligned with the audio/MIDI content already in session and possibly
being played back at the time of the recording. never again it gets
adjusted no matter what jackd parameters change later, be that for worse
or better. that's it.
please understand that this is the only kind of latency compensation
qtractor does and nothing else. nb. qtractor does NOT compensate for
in-line output or plugin chain latency. never did and quite frankly it
won't do so soon, i'm afraid.
i really don't see how having distinct jackd i/o latency settings
(buffer-size, periods, sample-rate) may lead to audio going out of sync
to MIDI--if it does get out-of-sync anyway, it is probably because
something else but latency compensation related, not to tell that
session-management has nothing to do with either. On 09/04/2014 07:49 PM, Ralf Mardorf wrote:
It doesn't report the latency a session was recoded 2 years ago.
Rui :)
please consider to automatically add to
File > Properties ... > Description
the jackd "in" and "out" reported latency ;). Since the MIDI
resolution
steps don't provide ms, frame information, a written note could help to
fix sync problems, without using a calculator.
(I don't need it, perhaps you could add an option to the preferences, to
uncheck this feature ;)
jack_lsp -l does report latency of every port
byee