Kurzweil 1000 GX
A two-rack-space guitar expander that carried a slice of the K250 sample library into any MIDI rig for just under two grand.
Overview
The 1000 GX is the guitar half of Kurzweil's 1000 Series, a family of rack-mount, 2U sound modules built around the company's VLSI microchip. The 1000 PX gathered the "greatest hits" of the K250 - piano, strings, choir. The 1000 SX and 1000 HX handled strings and horns. The GX was the guitar expander. Each Series 1000 instrument carried up to 120 of the same 16-bit floating-point, digitally sampled sounds that made the K250 famous, and the new chip let Kurzweil bring the line in at just under $2,000.
The GX has 20 voices. The 1000 PX and the K1000 keyboard carried 24. Per Kurzweil's own advertising, the point of the series was to free players from "the expressive limitations of 12-voice or 16-voice systems." Twenty voices let a player stack parts, build multi-voiced sequences, and grab big two-fisted chord shapes without the note-stealing that plagued cheaper modules. The series also scaled. Combine all four 1000 Series modules and the system reaches 84 voices across 8 outputs. A player could start with one expander and grow the rig module by module.
The GX's job was guitar timbres. Kurzweil's advertising billed the 1000 Series as an "affordable, modular way to add the extraordinary Kurzweil sound library to any setup," and the company emphasized that all the expanders had extensive programmability for synth sounds too. So the GX was not purely a preset guitar box. The series was introduced in June 1987. By the following year Kurzweil was promoting Sound Blocks for the line, with more planned for the 1000 GX, SX, HX, PX, PX Plus and AX Plus modules.
The GX found at least one notable home. In a later interview, a veteran player recalled moving off synthesizers and using the Kurzweil 1000GX Guitar Expander module for a few years before shifting to other instruments. For some working musicians it was the guitar-sound solution in a rack, at a time when sampled guitars were the only way to get the articulation and "bite" of a real guitar into a keyboard rig.
Kurzweil's launch positioning was "just under $2000" for the series. A contemporary dealer advertisement listed the 1000 GX at $1,497.00, well below the series' opening number. Keep that gap between list and street in mind when judging what these modules actually sold for. The K1000 keyboard was slated at $2,495.
Trade press coverage was warm but promotional in tone. Mix (March 1988, p.131) ran the "price you have to pay to be free" campaign, setting the 20-voice GX against the 12- and 16-voice limitations of competing modules. That language came from Kurzweil's own advertising, not independent measurement. Recording Engineer (December 1987, p.39) carried the same voice-count comparison. Mix (October 1987, p.249) documented the June 27, 1987 introduction date and described the series as making "Kurzweil 250-quality sounds" available in four rack-mount modules. Read these as period marketing placed in the magazines, not bench tests.
On the documented record, the GX is not a self-contained instrument. It is a 2U rack module with no keyboard. The K1000 filled that role for the PX side of the family. Anyone buying one today should expect a MIDI sound source that needs a controller, and should verify the Sound Block and program content of any unit they find, since the series' expansion story was still unfolding in the period coverage.
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