nothing in the hardware market will morph loops, retaining their rhythm and tempo if you change pitch
or retaining their pitch if you morph their tempo besides the Repeater.

Imogen Heap now augments her live show with Ableton's LIVE, a software program
run on a laptop utilizing separate midi footpedals or controllers.

Ableton's live, unlike the Repeater, does NOT HAVE 1st loop capability.

In other words, you have to use some kind of a live loopign VST plugin or standalone app
if you want to make a loop from scratch that DOESN'T have a prearranged tempo.

Because I'm good friends with Zoe Keating who has toured with Imogen, I'm fairly certain that she is
using a repeater (or two) in conjunction wiht Ableton's LIVE.

On a PC, If I were you, I would invest in a decent laptop (and run WIN XP NOT WIN Vista)

Then dowload the wonderful freeware program MOBIUS (until the imminent release of MAtthias Grob's
LOOP V hits the market which should be soon) and use it as a VST instrument to record your
first loop, then have it's tempo drive Ableton's LIVE via midi.

Be prepared for a considerable learning curve and a considerable economic investment (Laptop, break out sound card,
Ableton's Live Softare, Berhinger FCB 1010 mid controls).

If you just want multi tracking (and don't need to change the pitch or speed of your tracks) wiht very high fidelity
and a radically smaller learning curve and finacial investment, do yourself a huge favor and
buy your self a one rack space LOOPERLATIVE. 8 full bandwidth stereo tracks that you can either sync together
or not.............................unbelievably easy to use. They normally will set you back $1500 but if you contact me off
list, I'm almost positive I can get you a discount on that normal price (as I"m demoing it for Looperlative at the up and coming
NAMM show). You do need to invest about $150 in a Berhinger FCB 1010 midi foot controller but it's a cinch to get this thing
working.........unbelievable easy and intuitive (and quick!) to learn how to program.

If you want pitch manipulation, then LIVE is your only change............unless Sony will put out an interactive live version of
SONY Acid (and why don't they do this).

Ableton's is avalable for both MAc and PC but Mobious is not , to my knolwedge. LOOP V will be, howver.

Zoe Keating, I believe is using SOOPERLOOPER on a MAC with LIVE if I"m not mistaken.
She's awesome if you haven't checked her beautiful looped cello music.

SHe's also played with Rasputina and Imogen and is a MAJOR player.

good luck and let me know if I can be of assistance.