Re: [LAU] New release of jack_delay

Previous message: [thread] [date] [author]
Next message: [thread] [date] [author]
To: Paul Davis <paul@...>
Cc: Linux Audio Users <linux-audio-user@...>, Linux Audio Developers <linux-audio-dev@...>
Date: Monday, April 18, 2011 - 11:05 pm

On Mon, Apr 18, 2011 at 05:21:46PM -0400, Paul Davis wrote:

That's a very typical value.

If you have an HDSP or any other card with ADAT (or MADI) interfaces
it can be interesting to measure the excess latency with a digital
loopback as well.

If this is much less than the value obtained when going through
the DA/AD converters, then the difference is an indication of the
type and lenght of the anti-aliasing filters used in the converters.

If these filters are linear-phase (i.e. a symmetric FIR), then
each of them will add a delay equal to half the length of the
filter, so the excess delay is a measure of the filter length.

Values I've seen so far appear to be much less than e.g. the filter
lengths used by libsrc or zita-resampler at high quality settings.

Ciao,

--
FA
_______________________________________________
Linux-audio-user mailing list
Linux-audio-user@lists.linuxaudio.org
http://lists.linuxaudio.org/listinfo/linux-audio-user

Previous message: [thread] [date] [author]
Next message: [thread] [date] [author]

Messages in current thread:
[LAU] New release of jack_delay, Fons Adriaensen, (Mon Apr 18, 8:21 pm)
Re: [LAU] New release of jack_delay, S. Massy, (Mon Apr 18, 8:51 pm)
Re: [LAU] New release of jack_delay, Robin Gareus, (Mon Apr 18, 9:24 pm)
Re: [LAU] New release of jack_delay, Paul Davis, (Mon Apr 18, 9:21 pm)
Re: [LAU] New release of jack_delay, Fons Adriaensen, (Mon Apr 18, 11:05 pm)