It's the brand new C. Bechstein Digital Grand that's just been released as an expansion for Pianoteq. (And when purchased before January 31st, you get a 50% discount on whatever other instrument pack that takes your fancy.)
(For those that are interested in these things: the drums in the above demo were done with Mixosaurus — which, like the Bechstein Digital Grand, also has its roots in Teldex Berlin, hence the name of the piece 'Berliner Jam'. The bass is MODO.)

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