Hi all,

I process a lot of my audio samples through external EQ's and
compressors by sending audio tracks to the appropriate outputs of and
recording the return on another track. I've noticed that after doing
this a couple of times my audio starts to drift out of time.

As an experiment I connected one of my interfaces outputs directly to
one of its inputs and recorded the output of one track onto another
track and then zoomed in so I could measure the delay. It seems there
is a 3.5ms delay. This is small in itself but multiplies enough after
a few iterations to make it noticable and a problem.

I was under the impression that software such as logic compensated for
latency by shifting recorded audio appropriatly. Am I mistaken or is
there something I might be doing wrong? Does anyone else have this
problem? I've noticed references to driver delay settings and the
likes but these are all under 0S 9. I am using Logic 6.3 with a MOTU
24 I/O on OS X.

Thanks in advance,

Tas.

TinyTas ) wrote:
As an experiment I connected one of my interfaces outputs directly to
one of its inputs and recorded the output of one track onto another
track and then zoomed in so I could measure the delay. It seems there
is a 3.5ms delay.


Does changing your buffer size affect the resultant delay in this test?
(I expect not).

This might be converter latency, though 3.5 seems like a lot. I'm on
Logic5/PC, and deal with similar issues, though I have no firsthand
knowledge with the Mac versions. FWIW, here is a post/thread that might
give you a hint, or not:

http://www.google.com/groups?selm=MP... sbcglobal.net


You should also try the Logic User Group at Yahoo groups.


- Brian

Logic doesn´t compensate like that. It compensates after recording and
running things online is like recording. You have to change your negative
delay settings by the amount of latency you´re experiencing. This isn´t too
hard as latency is always the same within one soundcard so if you´re having
3.5 ms delay on the inputs all you have to do is select the track that
you´re sending out and set the delay parameter to -3.5 ms, pretty simple. If
you´re working with midi-sounds coming in thru the inputs you can set an
overall midi-delay in the synchronization-settings. Logic´s own compensation
applies to dsp-cards like UAD1 and TC Powercore. This is not a Logic-only
issue, all equipment has latency-analogue stuff too. Midi notes has about
0.7 ms per note so if you take a 5 note chord you will experience the same
timing problems so if that´s a problem to you, a lot of delay shifting will
have to be done on all systems.

--
Henrik Krogh

"TinyTas" skrev i en meddelelse
om...
Hi all,

I process a lot of my audio samples through external EQ's and
compressors by sending audio tracks to the appropriate outputs of and
recording the return on another track. I've noticed that after doing
this a couple of times my audio starts to drift out of time.

As an experiment I connected one of my interfaces outputs directly to
one of its inputs and recorded the output of one track onto another
track and then zoomed in so I could measure the delay. It seems there
is a 3.5ms delay. This is small in itself but multiplies enough after
a few iterations to make it noticable and a problem.

I was under the impression that software such as logic compensated for
latency by shifting recorded audio appropriatly. Am I mistaken or is
there something I might be doing wrong? Does anyone else have this
problem? I've noticed references to driver delay settings and the
likes but these are all under 0S 9. I am using Logic 6.3 with a MOTU
24 I/O on OS X.

Thanks in advance,

Tas.