Atari ST Emulators
'The Pacifist' by Frederic Gidouin runs without the need of extra ROM-cards... At 100% on a DX4-100, it supports music and sound, version 0.47 emulates STe- code, but when for instance Cubase Audio can be run depends on the I/O that still is in very beta-stasis-and-alike now.
you can see for yourself at : http://www.pacifist.fatal-design.com/