Re: FlyLoops and electronic instruments

[Jeffrey Larson <jeff@zonemobius.com>]

Per has already responded well to several points, I'll just add a few  
things.

 > I know mobius can handle multiple loops in parallel, as can  
flyloops ... and
 > I think the approaches we use are somewhat similar ...

 From what I have read, it appears that Flyloops is designed more for
"arrangement" looping in the vein of Ableton Live but with what is
commonly called "first loop capability".  You record fragments of an
arrangement and then combine them in various ways, maybe soloing over
the top.

Mobius is designed more for "evolving improvisational" loops that are
recorded then modified over time with functions like overdub, insert,
multiply, trim, replace, shuffle, and most important a feedback
control that lets the loop layers decay gradually while you overdub.

What Flyloops calls "loops" is what Mobius calls "tracks".
What Flyloops calls "A->B" is what Mobius calls "loops" with
the LoopCount parameter limited to 2.

Flyloops doesn't appear to have the concept of what Mobius calls
"layers", an infinite history of the evolution of the loop that
you can move around in with the Undo and Redo functions.

To draw a hardware comparison, Mobius is obviously closest to multiple
synchronized EDPs where Flyloops is closest to the Looperlative.

 > - full sync - meaning start/stop recording only at the masters  
loop boundary
 > .. so all loops start/stop with the master, and are a multiple of  
the master
 > loops length

This is what Mobius calls "Track Sync".  The recording of one
track can start and end at a certain location in the master track.
This is often the master track start point, but it can also
be a subdivision of the master track (cycles and subcycles).

 > - partial sync - start recording whenever I tap in, but when I tap  
out ..
 > wait until the loop is some multiple of the masters length ... so  
all loops
 > are a multiple of the length ... but will start/stop only at a  
particular
 > offset to the master.

If I understand correctly, this is closest to what Mobius would
call a Time Copy to get an empty loop in sync with the master, followed
by an Overdub or Multiply to begin recording into the empty loop
at the current offset.  To do this in Mobius with one switch press  
you would
have to write a script.

 > TEMPO/PITCH SHIFT:
 > I haven't programmed this yet... so currently there is no tempo or  
pitch
 > shifting

There are two fundamental concepts here.  One is "rate shift" which is
a change in playback rate similar to a variable speed control on a
tape deck or turntable.  This changes the tempo and pitch at the same
time.  The other is "pitch shift" which involves complex DSP
algorithms to change the perceived pitch without changing the tempo.
The two can be combined to get "time stretch" which is a change in
tempo that does not change the pitch.

Time stretch is one of the holy grails of looping but it is difficult
to do because the algorithms that sound best require too much CPU to
be done in real time on an average PC.  The ones that can be done in
real time don't sound as good.  It is a tradeoff and doing it well
requires a fairly detailed knowledge of DSP algorithms like FFTs and
filters.  One of the better implementations is found in Ableleton
Live.  The recently announced Virtual Repeater will probably do this
well.

Rate shift and time stretch also cause enormous complications
if you are trying to support external synchronization with a MIDI
clock or a VST host.

 > TAP TEMPO:
 > Mobius does this ... Flyloops will, once pitch/tempo shift is  
complete.

Mobius does not support tap tempo in the sense that you can record a
loop, then tap two switches to change the tempo of the loop without
changing pitch.

 >   And .... you could set up an external
 > source to trigger the rec button ... so sync that way .... but you  
could NOT
 > track to an external drum machine as you changed tempo for example.

Syncing to a drum machine is more complicated than automating the
record button even if you are not changing the tempo.  Since the two
devices are not driven from the same clock they will eventually
drift apart.  Doing this properly requires the looper to continually
monitor the MIDI clock stream and make periodic adjustments
when it notices a drift.

 > VST:
 >  flyloopscannot run as a VST (yet).

Some friendly advice...you will have far more commercial interest if
you provide VST support rather than Rewire support.  Rewire is not
nearly as flexible as VST for the user.  But I am interested in
knowing if Propellerhead grants you a license.  I gave up on that
awhile ago because of their policy of not granting licenses to
"individuals".  You have to convince them you are a "company" though
they don't define exactly what that means.

Jeff