Trend price : 200€
Rackmount module expander of the famous D-50 L.A synthesizer: The D50 synthesis engine is still considered today as one of the most interesting ever made.
Company: Roland
Model: D-550
Class: Synth module
Dates: 1987
Country: Japan
Weight: 2,5 kg
Dimensions: 480 (W) x 410 (D) x 90 (H) mm
Synthesis: L.A digital
Polyphony: 16 voices
Multitimbric: 1 part
Algorithms: 7 modes
Filter: digital low pass
LFO: 3 modulators
Envelope: 2 EGs
Effect: reverb + chorus
Memory: 64 slots
Midi: IN / OUT / THRU
CPU: UPD78312
DAC: BB HP54HP
OS: latest is 1.02V
Demo: 1
Video: 1
Review: 1
DOWNLOAD: user manual - service manual -
Overview
a 2 units expander. Main panel features a blue display and
36 buttons for sound edit
Terminal connectors:
-
Midi interface
-
main out
- headphones out
- data card slot
Voice
16 digital voices polyphony, 16 bits, DAC BB PCM54HP at IC10.
The minimal part is the PARTIAL composed by 2 UPPER tones + 2 LOWER tones then 4 combined tones make a PATCH. TONE has value for relation between both partials and each partial is like an oscillator with various synthesis chain elements: WG (voice) + TVF (filter) + TVA (amplitude)
Wavegenerator
128 kb ROM PCM wavetable and a digital waveforms generator:
- 47 Transient PCM acoustic
- 29 Transient PCM spectral loops
- 23 Transient PCM normal loops
-
2 digitally generated sawtooth and square wave
Algorithms
WG combines partial synthesis elements with a digital ring modulator in 7 possible pathways or algorithms.
Filter
structure is based on the TVF time variant filter which is a digital 4-poles resonant lowpass filter
LFO
3 delayed digital modulators and 3 destinations:
- amplitude
- pulse waveform width
- filter cutoff
Envelope
- EG 1 amplitude : 5 segments + 5 times
- EG 2 filter : 5 segments + 5 times
All partials have their own EG for both amplitude + filter, for a total of 4 TVF EGs and 4 TVA EGs
Effect
32 reverbs + 7 choruses modulations
Memory
64 RAM internal patches
Review
OK: sound / cheap
NOT : earlier OS / edit without PG1000 programmer
"All-time classic: Great sound!"
Text , review, special demos copyright polynominal.com / Eric Pochesci
