The Yamaha AN1x Synthesizer mailing list

Hi everyone, I need help with my Yamaha AN1X recently bought it on ebay and came with a power source KPA3 11.5v --- 600ma and when I play the preset change or tone or sound as if I was modulating the sounds but On the screen does not appear any message, is it because I do not have the original power supply? IS THIS PROBLEM COMBLE? I tried it with a power supply of 12v --- 1.0a and I had the same problem, I need help please, does anyone know which is the most suitable replacement power supply? That works well and where to buy it? I appreciate any reply. Greetings .