skywalker
Dirk from what I understand there are slight differences in the control unit (see listing here) with regards to the number of included instruments/sounds. The RSC3 seems to be to retrofit pianos without a previous silent system installed, the VSH3 is for existing silent pianos thus does not include the mute rail. The sensor system seems to both electromagnetic (the link above says optical but then electromagnetic below). I bought the VSH3 to retrofit an old M100 model with optical silent system and definitely is the latest elector magnetic rail.
Search for ‘Yamaha SC3 vs SH3’ and you will find some Yamaha shop links with more information. You can also call a Yamaha shop for more info. I live in the US but got my unit from Piano Ebert in Konstanz Germany.
Vincent Muck was super helpful and savy.
Vincent Muck
MUSIK-EBERT GmbH
Hussenstr. 45-49
78462 Konstanz
Tel. [+49(0)7531/1360-71](tel:+49(0)7531/1360-71)
Fax [+49(0)7531/1360-70](tel:+49(0)7531/1360-70)
Email: [[email protected]](mailto:[email protected])
Hope that helps!