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"This 303 has been modified with the Quicksilver 303 CPU upgrade!
A great way to get this amazing upgrade without having to send away your 303 or deal with installation.
All LEDs have been upgraded to a nice diffused BLUE.
This machine has also had the switches replaced with new ALPS sealed tact switches, so there isn't any problems with buttons double triggering.

The Quicksilver 303 CPU adds support for:
* MIDI input/output
* USB-MIDI
* realtime pattern editing
* pattern MIDI output
* sysex pattern dumps
* realtime mode switching
* filter control over MIDI
* pattern randomize
* MIDI sync
* updateable operating system
... and much, much more.

With the Quicksilver 303 upgrade, the 303 has become an amazing interactive live performance synthesizer.
You can create and edit patterns without ever stopping the sequencer.
You can find out more about the Quicksilver 303 upgrade here:
http://www.socialentropy.com/quicksilver
A video showing some of the cool things the Quicksilver 303 is capable of: Quicksilver 303 MIDI CONTROL" [
posted here]