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Yamaha DX7




dx7 e! grey matter
  audio demo trend price : 250€ (400€ with E!)
manual schematics factory patch demo video comments

YAMAHA DX7 E! grey matter Response (1983)

The DX7 was the first affordable synthesizer implementing FM synthesis designed by John Chowning.

The FM revolution changed the sound forever.


synth detail

info KEYBOARD (weight: 15 Kg) 61 keys with velocity and aftertouch.
The main panel features a 16 X 2 lines display , 42 buttons, 2 sliders for volume and data entry.

Rear panel terminal connectors:
- mono out
- Midi interface
- headphones out
- breath controller input
- sustain footswitch input
- portamento footswitch input
- volume pedal input
- modulation pedal input

main core 8-bit CPU Hitachi HD63A03X manages 16 digital voices based on FM synthesis.
The IC YM2128 generates 6 syncable sinewave oscillators or operator each with individual volume settings and detune.

Fm key  Scaling

edit SYNTHESIS there are 6 sinewave operators organized as algorithms, assigned as carrier or modulator, linked between them on different pathways interacting on their harmonic contents depending on the variable feedback strength.
- carrier: defines the amplitude and the spectral frequency
- modulator: sets the sound timbre and the relative harmonic contents.

DX7 offers 32 different combinations algorithms with frequency ratio or fixed frequency: the output is fed back to its input with 7 different levels feedback, as general rule, high values feedback results in richer harmonic contents.

fm dx

lfo LFO
there are 2 digital modulators with adjustable start delay and sync retrigger:
- PMD modulates pitch
- AMD processes the amplitude
Both LFO offers 6 waveforms : sine, triangle, saw up/down, square and sample & hold.

the IC YM2819 generates 7 envelopes:
- 1 EG pitch: 4-segments structure + 4 time levels.
- 1 EG for each operators: 4-segments structure + 4 time levels
The Scaling Level is a very precise key follower with 4 linear / exponential curves

memory MEMORY holds 32 patches, doubled if a cartridge RAM1 is present.
The backup memory works with a CR-2032 lithium battery soldered to the board,
Be aware that there is no ROM factory recall, so it is necessary to use Midi exclusives data for this job.


repairGREY MATTER E! BOARD EXPANSION This special board can be fitted to upgrade to machine to new functions and features:

- multitimbral
- ten times RAM slots
- monophonic with 8 voices stack
- adjustable random detune (variable range set)
- a user-friendly TX programmability
- controller remap
much more on the Dx7 E grey matter manual.

dx7 grey matter picture installation boardyamaha dx7 upgradevarious e!eprom set
motherboard closeuppic eflat remove

GALLERY E! : board requires a Dx7 with latest OS (only upgradable by EPROM) and requires some advanced skills for soldering and cutting circuit tracks.

lfo EDIT the DX is not famous for easy edit functions, some computer-based editors can help:
- Atari ST: Dx-android, Dx expert or caged ST
- PC: Soundiver, Midiquest, DX-manager, Synlib ...
- MSX: YRM 103 -102 cartridge Voicing program also YRM304
- IOS: Yamaha DX7 /TX7 / TX816 Editor
- Hardware: if you are lucky enough, you can try the mega-rare Jellinghaus DX Programmer

Jellinghaus DX Programmer

atari st editor
atari st editor caged

android dx atari st
Ios editor missing link

family OP6 DX FAMILY After one year Yamaha released the super deluxe version Dx1 that later became the cheaper DX5. There' s also an expander module TX-7 then the huge TX-816 a pretty impressive rack modular version.

TX802 - Tx816 - Tx7 - Sy99

dx7 family tree

VST PLUGIN / SAMPLED VERSION there are some free and commercial samples set:

  name price link demo
dexed VST plugin DEXED free
effet dexed FM emulation
hexter HEXTER Free effet hexter dx7
odsay MDA DX10 free effet mda dx10
oxe fm OXE FM SYNTH free effet oxe fm synth
vx7 vst plugin VX7 free effet n/a
fm8 Native instruments FM8 commercial effet fm8



demo 1 - official demo from1983 p1
demo 2 - official demo from 1983 p2
demo 3- official demo from 1983 p3

effet Soundcloud DX-7

demo1 demo2 demo2


Yamaha DX7 Frequency Modulation YAMAHA DX7 DEMO 1 Yamaha DX7 E.Piano
Frequency Modulation DEMO 1 E.Piano

dx7 fm synth





fm dx
DX7 Service manual


testthe second DX7 version offers some update and sounds a bit different, mainly for the different DAC with higher resolution. I made a little comparison test:



original scan


yamaha dx7 milestones


performance on dx7 fm synthesizer


dx7 classic flyer

dx7 classic flyer


custom models
GALLERY: custom models


original scan

original scan
PIC: dx7 tatoo


original scan
PIC: it... need repairs!


fun dx7
VID: fun guy playing DX7!

fun dx7
VID: Cesar Camargo Mariano- an incredible DX7 player! rhythm by Roland tR-909





- raw sound
- FM concept


- keys dynamic
- weight
- edit


"We are here in front of the history! Massive sound, raw-powerful, hard to tame!"


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all snapshots*, sounds, texts copyright Polynominal.com / Eric Pochesci
*John Chowning found on wikipedia
*tatoo picture unknown author.
*Dx7 broken unknow author

Yamaha dx7 4 out of 5 based on 16 ratings. price €400