Frank,
I have the SD1, PA1X and Tyros all at my store. I'm not a keyboard player or singer but I do demo these products alot just by playing a few chords and simple ad lib melody's. I use alot of tune 1000 songs to demonstrate the vocal harmonizers or I just play some chords on the left hand and sing using factory preset vocal setups. On Yamaha I usually use country men or some jazz preset and on the Korg I just use the factory default or I'll select the preset called I believe "blues in C Major" which allows me to just sing and not have to play chords on the keyboard. I have not noticed any major differences in the three. I don't notice chipmonk sounds, but again, I'm not a singer and maybe I don't put the harmonizers through their paces as some do.


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George Kaye
Kaye's Music Scene
Reseda, California