WORKING CONDITION: Excellent. This Super JD sounds incredible. The bass is massive, the midrange is punchy, and the high-end is crisp without being harsh or strident. All patches (including the RHYTHM section) load instantly with no issues, and the display screen is sharp and extremely legible. We believe the original backlight may be burned out or dim, but it is otherwise very easy to read and crisp. 

PHYSICAL CONDITION: Excellent. There are very minimal signs of age on this vintage machine. Both card slots are clean, the screen is void-free, the rotary Value selector is smooth, and all iO jacks are in excellent physical condition. 

INVENTORY #59883

BRAND: Roland 

MODEL: JD-990 Super JD

FUNCTION: Rackmount Synthesizer Module

PRODUCT DESCRIPTION: This listing is for a 1993 Roland JD-990 Super JD Rackmount Synthesizer Module w/ Manuals. The Roland JD-990 Super JD is a legendary 2U rackmount digital synthesizer module produced by Roland from 1993 to 1996. Widely celebrated as one of the finest digital synths ever made, it serves as the enhanced rackmount counterpart to the famous JD-800 keyboard. It is highly sought after for its pristine high-fidelity sound, legendary lush pads, sharp resonant filters, and expansive sound-design capabilities.

SPECS:

• Serial # ZF36567
• Date of Manufacture: August, 1993
• Synthesis Engine: 24-bit digital PCM (Sample playback + digital processing).
• Polyphony: 24 voices maximum.
• Multi-timbral Capability: 8 parts (7 instrument parts + 1 rhythm/drum part).
• Patch Structure: A single Patch can consist of up to 4 Tones (layers). Each Tone has its own independent oscillator, filter (TVF), amplifier (TVA), and envelope generators.
• Special Structures: Unlike the JD-800, the JD-990 features 6 structure types allowing for:
  • Ring Modulation
  • Oscillator Sync
  • Frequency Cross-Modulation (FXM) with 8 color settings
• Synthesis Type: PCM Digital (Linear Arithmetic / Wave FX). 
• Polyphony & Partially: 24-voice polyphony, 8-part multi-timbral.
• Structures: Unlike the JD-800, the JD-990 introduces advanced patch structures including ring modulation, oscillator sync, and frequency cross-modulation (FXM).
• Waveform ROM: 6 MB internal expandable PCM memory, featuring expanded waveforms over the original JD-800.
• Display: A large, highly graphical backlit LCD screen that dramatically simplifies editing compared to standard rack units of its era.
• Expansion Slot: Features a dedicated slot for Roland's SR-JV80 series expansion boards. When paired with the coveted SR-JV80-04 Vintage Synth board, it unlocks an exclusive, custom set of 256 patches designed specifically to exploit the JD-990’s superior architecture.

ACCESSORIES INCLUDED: Includes power cable and all original manuals. 

• Roland Super JD Owner's Manual I (User's Guide)
• Roland Super JD Owner's Manual II (Reference Guide)

UNPACKAGED WEIGHT: 14 lbs.

UNPACKAGED DIMENSIONS: 19" x 4" x 12"