Archive of the former Yahoo!Groups mailing list: Yamaha CS80
Subject: RE: One key problem - always at highest brilliance...
From: <joachim.milson@...>
Date: 2013-12-03
Check velocity by ear for D#5. Compare with an other key.
From the TSB, through the TKC and until the TWS, the velocity and the aftertouch signals follow the exact same path. So most certainly velocity won't work neither for D#5. So check it.
Did you change the NMJ4558 (IC4) on the TSB2 board ? If so, check the solders. If you added a socket, check that no pin of the chip was folded during insertion.
If all this is OK, and if you use sockets, it shouldn't be too long to try and swap IC4 and IC5 for instance. This would help determine if IC4 is defective.