YES you can use a pedal from yamaha, u can use any pedal, u can even stick a nail into the sustain jack
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and it will work (no kidding)
Sustain pedal is just a momentary switch it just looks different, YOU can use any pedal U want, AMEN.Enjoy your va-7, I have VA-76 I bet I can Answer Any question about VAs(If I would be able to type faster) I just Don`t like Styles like LATIN, JAZZ, Swing...
When you get your va-7 Check out these styles on Zip Disk: HITMIX , Dt`fox, Ballade, Esapecialy the intros.