Hola latinjazz, mira algún módulo de Kurzweil, no creo que en sonido de pianos hayan mejores, y por lo que veo llevan secuenciador:
K2500R RACK MOUNT SYNTH
Based upon Kurzweils K2000 and utilizing their VAST technology, the K2500R combines several functions to become what Kurzweil calls a production station. The K2500R offers twice the polyphony and on-board system RAM. System software is easily upgradable via Flash ROM, that allows the user to update their system via SCSI or floppy drive.
A full function 32 track sequencer is built into the K2500R. There are 16 16 song tracks and 16 arrangement tracks, 768 ppq, linear / pattern / and step record modes, full editing, and more.
KURZWEIL - K2000VPR
The K2000VPR, like its predecessor, the legendary K2000R, is a 24 voice, 16 Channel Multi-Timbral, 3-Zone Midi Controller, V.A.S.T.® synthesizer workstation
with 32-track sequencer. The K2000VPR is a complete, cost effective, total solution for the first time buyer or accomplished pro. The features, versatility and expandability of the K2000VPR make it the only synth module you will ever need.
http://www.synthman.com/kurzweil/index.html
http://www.synthony.com/museum.html
http://www.sonicstate.com/synth/cfman.cfm?manid=20
Espero que te haya ayudado.
Saludos