via this auction

The Matrix-12 was available with a optional pressure-sensing keyboard, but this one doesn't have it.
The power section works on all voltages worldwide (90-130VAC, switchable to 190-260, 50-60Hz).
The unit had one fault I was aware of: one voice's filter did not pass the self-tune. I had this repaired by Hayashi-san at Symplex in March 2023. As outlined on the receipt shown, he diagnosed the replacement of the voice 10 filter chip (3372, shown; I will include the original bad chip in the purchase). Finally, he did a complete test, and found some more work to do: he cleaned the bend and mod wheels, volume pot, six encoders, eight switches, and upgraded to the latest v1.6 ROMs. The unit now always passes all five self-tune tests as shown on the display quickly, even immediately after turning on."