re: do any slave sync?

[Rainer Straschill <moinsound@googlemail.com>]

Luis,

this thread is incredibly funny insofar as the "re:" added to the
subject line by the email programme of the first guy who responded got
me confused at first, because I read "redo any slave sync?" - I beg
your pardon? ;)

However, to the sensible part:
> Do any of the current existing hardware loopers sync when being slaved?

Seriously, none should "drift with time" as you mention, because the
definition of being slaved is that they do not drift with time.
("Syncing" here meaning that the slave receives a steady stream of
timing information from the master (e.g. MIDI Clock, MTC) and changes
its internal time base so it is aligned with it. So even if this
process may happen with some flaws, and devices may loose the
master-slave relationship, as long as the slave is a slave of the
master, what you describe would not happen. So consequently, this may
mean that the master-slave relationship got lost?)

Things I noticed, however (not necessarily with loopers):
1. some devices tend to have a steady offset with regard to the device
they are synced to. This can be explained very easily, simply because
the MIDI sync signal takes its time for being generated, routed and
interpreted. For that reason, some e.g. drum computers and also
software programs have a setting to compensate for this offset. So if
you do not change your system, you can bring that offset to zero.
However, this will never lead to the devices drifting, they just are a
little off in perfect sync.

Bob, you also mentioned sync experiments you conducted with the LP1.
Does the LP1 also have the aforementioned kind of "clock delay
compensation" setting?

2. some devices (both master and slave) tend to jitter, e.g. increase
or decrease speed by a small amount. While this may have ugly effects
(mainly depending on how the slave reacts to it - the Repeater at
least in sw 1.x had a very jittery clock, but did sync fairly well as
a slave - see below, which led to some MIDI-synced delay effects, e.g.
of the Roland VBass producing ugly clicks), this would also not lead
to them drifting apart (as long as the devices stay locked).

Summarizing: what you describe (if I understand it correctly) looks
like the devices completely loose sync. My experience with hardware
loopers in this regard: the only hardware looper I ever owned (and
still own) is the Repeater (only used SW 1.x so far). It would sync
just fine in the majority of cases, however, there were situations
when I lost sync, most prominently when I hit "Slow CFC" on a
non-Hitachi-controller CFC. In one (documented on my "Neinnein auf dem
kleinen Weg" album, recorded live in Desenzano at a concert organized
by Luca Formentini) event, the Repeater was synced (I never used it as
a master because of its crappy clock, see above) to a Quasimidi
Sirius. In the midst of a (half-hour-long) song, the Repeater would
loose sync suddenly and stop playback. I tried to restart it, and
succeeded. However, before and after that (and on any other occasion I
can remember), the two (or other two, like MC505 and Repeater or
Eclipse and Repeater) stayed in sync just fine.

Best,

          Rainer

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