Rui Nuno Capela rncbc at rncbc.org
Wed Sep 21 14:39:31 UTC 2016

On 09/21/2016 11:24 AM, Perry Nguyen wrote:
> Though after reading your post to LAD a couple times over it seems like
> there is possibly overlooked but important incongruity between BPM and
> "linear/real-time".. and perhaps that limits the ability of word-clock
> time designators like JACK from seamlessly following BPM? If that is the
> case it is still unclear to me what the specific technical details of
> that incongruity are.

(continuing my own babbling...:))

read this?
(JACK Transport Limitations)

ok. now from the top of my head.

a. jack-transport/timebase (JT) is a centralized master/slave model, 
including its API approach; corollaries follows: all JT clients start 
and stop on demand and at the same time; netjack clients might drift 
apart, unless they implement some sort of PLL/DLL device (anyway, this 
assumes one of the participants is master); time reference is absolute 
frame position, constant sample-rate (frames/second), starting from a 
designated master application, linear (tape-like) timeline model (a 
song, session or project as a whole length continuous composition or 

b. ableton-link (AL) is a distributed metronome facility and API; any AL 
client may or not be playing its thing on any given time, but when they 
play,  they *should* start and sync (internally on their own premises) 
on beat boundaries on their own best-fit strategy model; time reference 
is tempo (BPM; beats/minute); tempo changes are broadcasted (well, dang 
truth is multicasted), may be initiated by any participant, then each 
other participant may react accordingly (or not) on their own chance, 
next cycle or phase, whichever fits best their own designed playback 
model--this is why, AL is more suited for loop-based contraptions that 
straight linear-tape model ones.

you can map AL to JT (timebase) if you will, but it's one master's job 
to do it--make the time calculations according to its own master, static 

rncbc aka. Rui Nuno Capela

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