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D4 - Image 1

D4

RackmountDigitalPolyphonic

Back in 1991, this single-rack-space powerhouse brought over 500 stereo-sampled drum and percussion sounds to life at a blazing 48kHz rate, making acoustic kits punch through mixes with startling realism that rivaled pricier gear.

Its digital PCM engine delivers 16 polyphonic voices across categories like 99 kicks, 99 snares, 92 toms, 55 cymbals, 76 percussion hits, and 80 effects, all velocity-sensitive for dynamic response. The front panel keeps things intuitive with a backlit two-line LCD, stepped data wheel for precise editing, large preview button, cursor keys, and ten function buttons, plus headphone out and volume knob. Rear connectivity shines with full MIDI In/Out/Thru (16 channels), 12 acoustic trigger inputs for pads or external audio, footswitch jack for kit stepping or hi-hat control, and four 1/4" outputs configurable as two stereo pairs or individual monos with seven-position panning. Program 21 kits by assigning sounds to 60 consecutive MIDI notes (root adjustable from 0-76), tweak volume, tuning, and grouping for effects like hi-hat muting.

Drummers and producers loved its trigger responsiveness and ease for live or studio use, often praising the broad, high-fidelity library as a main sound source that integrated seamlessly with existing setups. A few noted the editing stays basic—no deep envelopes or effects—but that raw power still holds up for vintage beats today.

Released

1991

Status

Discontinued

Synthesizer
Format
Rackmount, Drum Machine
Type
Digital, Sample-based, PCM
Internal Battery
-
Voice
A/D
Digital
Polyphony
Polyphonic
Oscillators
-
Oscillator Type
-
Voices
16
Tracks
21
Filter
No
Envelopes
-
LFO
-
Effects
No
Expression
Aftertouch
No
Velocity
-
MPE
No
Additional
-
Software
-
I/O
Audio In
-
Audio Out
4 x 1/4" (Main L/R, Aux L/R)
Headphone
-
MIDI
In, Out, Thru
MIDI Type
DIN (5-pin)
Ports
Trigger In, Footswitch
Wi-Fi
No
Workflow
Arpeggiator
-
Sequencer
-
Mod Matrix
-
Memory
21 programmable drum kits
Measurements
Dimensions
-
Weight
-
Last updated Feb 26, 2026