[Jack-Devel] I'm confused about latency

[Alexandre BIQUE]

On 4/5/19 11:48 AM, Ralf Mardorf wrote:
> On Fri, 5 Apr 2019 10:36:02 +0200, Alexandre BIQUE wrote:
>> 2.5 ms is quite a lot
> 
> A lot of people don't care about it. A digital guitar stomp box might
> allready add additional 5 ms and people often don't notice it.

The use case are Ableton link and midi clock, of course it won't be
perfect but any best effort we can do to make it more accurate is welcomed.

>> I'm skeptical that people want to put a feedback cable into their audio
>> interface and measure exactly how much latency is introduced, and then
>> configure their tools with some mystic latency compensation. I really
>> think that if we can get some values from the OS which minimize the
>> error that would be better.
> 
> On Linux Ardour suggests to measure the round trip latency and on
> iOS Auria Pro suggests to do a measurement, too. The gearslutz.com
> forums discussed this and recommend to measure if "you really need to
> have sample accurate timing". It's not unusual to connect a cable and
> to push a button and perhaps to manually add a value to a dialog, if
> it shouldn't be automated. How should the additional device's latency
> be reported for e.g. an ADAT device connected to the audio interface,
> even if all other latency would be reported?

Yes I also think that if one can achieve this in a user friendly way it
can be interesting.

Thank you,
Alex.