OB-Xd

OB-Xd emulates the Oberheim OB-X, OB-Xa, and OB-8 analog synthesizers with intentional differences and improvements. The sound isn’t a 100% accurate simulation of the original hardware, but OB-Xd captures the sonic character of its analog counterparts very well. The features are mostly borrowed from the Oberheim OB-X: a pair of detunable oscillators with unison, a noise generator, a couple of envelopes, an LFO, and a great-sounding filter.

The interface is clean and well laid out, making it easy to pick up even if you’ve never used an Oberheim-style synth before. OB-Xd comes with a large collection of presets that deliver classic Oberheim sounds. It works on Windows, macOS, and Linux, and an iOS version is also available. The Surge Synth Team (the open-source team behind Surge XT) is developing OB-Xf, a fork of the original open-source OB-Xd project. OB-Xf is still in beta, but it already sounds great and definitely rivals OB-Xd.

The overhaul adds a new 4-pole filter mode, all Oberheim Xpander filters, a second per-voice LFO, morphable waveform knobs, a ring modulator, and multimode noise. OB-Xf is available in AU, VST3, LV2, CLAP, and Standalone formats. Keep in mind that patches from OB-Xd are not compatible with OB-Xf.