“Obxd is based on the Oberheim OB-X. It attempts to recreate its sound and behavior, but as the original was very limited in some important ways a number of things were added or altered to the original design. If you’re unfamiliar with the OB-X, its user manual can easily be found from various sources on the net.
The Obxd was designed to sound as good and as rich as the original. It implements micro random detuning which is a big part of that sound. However, it was not designed as a self-contained completely independent soft-synth. It needs to be contained within a VST framework where things like transposition, automation, layering, arpeggiation, etc., are available. Also, like many synths of the OB-X’s generation, the Obxd has no internal effects so its sounds and textures can be greatly enhanced by the use of additional processing like chorus, reverb, delay, etc.”
Source : obxd.wordpress.com