Fran's right. Sounds to me like you're looking for what Roland has. It's called Chord Memory. There are presets and user settings.
The cheapest Roland synth that has "Chord Memory" is the Roland Juno-D. It's just a basic synth, but it does have the function you're looking for. The next model up from that would be the Juno-G.
You may be able to find a used Roland RS-50 or RS-70 too. The 50/70 are essentially the same synth, but the RS-70 adds a 16 tracks 100,000 note "pattern" sequencer.
The Juno-D runs: $595.00
The Juno-G runs: $999.00
Used RS-50/70 runs: $400.00-$550.00
Also keep in mind these are synths. The GW-7 is an arranger. I can't think of any arranger (current available models) that has the Chord Memory.
[This message has been edited by squeak_D (edited 07-18-2006).]
GEAR: Yamaha MOXF-6, Casio MZX-500, Roland Juno-Di, M-Audio Venom, Roland RS-70, Yamaha PSR S700, M-Audio Axiom Pro-61 (Midi Controller). SOFTWARE: Mixcraft-7, PowerTracks Pro Audio 2013, Beat Thang Virtual, Dimension Le.