Oberheim OB-Xa

"Like the OB-X that preceded it, the OB-Xa was available in four-, six- or eight-voice versions and sported a somewhat simplified dual oscillator signal path. The OB-Xa, however, added a 24 dB filter to the OB-X's 12 dB job and, in fact, you could create layered sounds that combined both for a more complex and engaging sound. And what a sound it was."

"What a sound [...] The OB-Xa may be the single phattest sounding instrument we have ever heard. Users who dare to click that Unison button may have to have their teeth re-enamelled. Yeah. It's big. As with all Oberheim instruments of the time, the OB-Xa could be lashed together with a DMX or DX drum machine and a DSX sequencer to form a complete Oberheim 'System'. Such a System in full swing was a sight to behold in those pre-MIDI days, a technological wet dream that was far out of reach of all but the most successful musicians of the day."