bristol binary package in Ubuntu Precise i386

 Bristol is a synthesizer emulator application. Bristol uses the sound card
 PCM generator and can be MIDI driven, furthermore it can be set to use the
 low latency scheduling feature of the kernel, reducing audio under runs.
 It can handle any number of simultaneous synthesizers (they all connect to
 the same engine). It supports splitting and layering the keyboard with
 multiple synthesizers on a single midi channel. Currently Bristol emulates
 the following keyboards: Moog Mini, Moog Voyager (Bristol "Explorer"),
 Sequential Circuits Prophet-5, Roland Juno-6, Yamaha DX-7,
 Hammond (single manual), Hammond B3 (dual manual).

Source package