Thanks! I'm just a HiFi hobbyist, Not a specialist at all🙂!
Sorry I don't have any experience for voltage conversion of Dp900 or DC901. However, some Accuphase CD player utilize low power transformer with jumper setting, J1 for 100V, J2 for 120V and J3 for 220-240V, IIRC.
If you can post a picture of the power board, perhaps we can figure out how to convert the voltage.