[LAD] Tests directly routing pc's midi-in to midi-out (was: Re: ALSA MIDI latency test results are far away from reality)

[fons at kokkinizita.net]

On Wed, Jul 14, 2010 at 11:54:35PM +0200, Ralf Mardorf wrote:

> I could record audio for kick, snare, hi hat and bass one after the
> other and mix it to one rhythm group and additionally I could record all
> instruments at the same time and send the recordings to you and you
> could do the same by yourself.

That is not a valid test. If the soft instrument that generates
these sounds aligns MIDI events to Jack periods, and you are using
a period size of 1024 as you say you are, it proves nothing at all.

Apart from that, it remains to be seen if *real* timing errors of
+/- 2 ms do 'destroy the groove'. To test this, make the same 
recording 

- without jitter,
- with 1 ms jitter,
- with 2 ms jitter,
- with 3 ms jitter.

and check if listeners are able to identify which is which,
or at least to put them into order.

What you have been doing so far is compare an 'exact' version
with one that has some unkown and uncontrolled errors. You could
'prove' anything you want in that way.

You are just jumping to conclusions and making gratituous
generalisations.


Ciao,

-- 
Je veux que la mort me trouve plantant mes choux, mais
nonchalant d’elle, et encore plus de mon jardin imparfait.
(Michel de Montaigne)