[LAU] : Netjack : like a charm :)

torbenh at gmx.de torbenh at gmx.de
Wed Dec 10 07:37:19 EST 2008

On Wed, Dec 10, 2008 at 08:16:29AM +0100, Mysth-R wrote:
> * I would like to test the --celt option. But I can't understand what the "N
> bytes per period" option are.

it tells celt to compress one period of data to N bytes.
i use -c32 for internet connections generally. sounds ok.
if you can cope with lower quality lower it and add more channels.

be careful to not max out the link, because this will give you netxruns.
using celt you will only hear a lot of them, but they degrade the

> * It seems that xruns on the master computer made some desynchronizations.

oh... right this can happen.
i need to think about how i can fix this.

> * On seq24, on the slave computer, I had to configure the option with "Jack
> Transport" AND "Master JACK" ... a bit disapointing... We lost so much time
> finding this very logical configuration.

sorry, i was not really clear about this.
netjack only synchronizes the frame count. not the tempo information.
So you need a Transport Master on both ends.

The problem is that the slave transport is basically running in the
future to compensate for the latency of the network link.

I cant know of tempo changes ahead of time. So its mostly
impossible, to add N frames, to beats:bars information.
Tempo changes would at least become flakey.

> * So the problem was seq24 on the slave machine was running at this own
> tempo. If the master use 120BPM and the Slave 110, they are not
> synchronized. But if you put 120 on both, it seems to be synchronized...
> Well I think there is a bug in seq24 or something. I didn't try with other
> softwares. But I have some doubt about the real tempo synchronization.

as stated, it only synchronizes the framecount.
netjack2 seems to do complete tempo synchronisation, but i dont know
if its latency compensated. and i also had somebody reporting,
that it just fails with an assert triggered.

> Thank you very much for this great apps that change our lives :)

no problem.
just spread the word. i still have the feeling, not many
people are using it :S

while there is obviously much use for it.

torben Hohn
http://galan.sourceforge.net -- The graphical Audio language

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