OBXD is a monophonic/polyphonic realtime VST-based synthesizer developed by 2DaT, Layzer and Breeze (at KVR) and recently ported to linux. An "unoffical" manual describing the additions/modifications brought to this softsynth version of the classic hardware synth by Oberheim, can be found here: OBXD -Unoffical Manual
OBXD can be run in any VST-host, such as Carla or Jalv.
A few patches of my own, using the LV2 version of OBXD: OBXD Patches 01 Extract the file in your .lv2 folder before starting OBXD.
A few more for LV2: OBXD Patches 03
A very nice collection of patches can be found here: Freesoftwaremusic
Various preset banks are available at KVR Audio here: OBXD Banks at KVR Audio in .fxb format for use with the VST version.