VOICES 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.
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
varable 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.
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.
ENVELOPE 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 holds 32 patch backup, 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.
E! BOARD EXPANSION This special board can be fitted to upgrade to machine to new functions and features:
- ten times RAM slots
- monophonic with 8 voices
adjustable random detune (variable range set)
a user-friendly TX programmability
much more on the Dx7 E grey matter manual.
INSTALL board requires a Dx7 with latest OS (only upgradable by EPROM) and requires some advanced skills for soldering and cutting circuit tracks.
EDIT the Dx7 is not famous for easy and real-time edit functions! if you are lucky enough, you can try the mega-rare Jellinghaus DX Programmer (worth 2000€!).
A cheaper way are the computer programmers, some of the first were available for
Atari ST : Dx-android, Dx expert or caged ST
PC-based: Soundiver, Midiquest, DX-manager, Synlib and others.
MSX: YRM 103 -102 cartridge Voicing program / YRM304
IOS: Yamaha DX7/TX7/TX816 Editor
atari st editor caged
Ios editor missing link
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 TX816 a pretty impressive rack modular version.