VOICE CPU HD63803XP Hitachi manages 8 voices - DAC is based on a IC YM3012.
main IC chip YM2414B features 4 OP + 8 combinations unlike previous DX7 synthesis is based on a 6 operators system with just pure sinewave and 32 combinations algorithms.
The tx81z ROM has 1 stored digital half sinewave on a lookup table that can be read in different way and speed (similar to PD synthesis concept) creating 7 extra harmonics sinewaves variations with partials overtones and fundamentals fixed settings. Tx81z does features "more waveforms" like subtractive synthesis, and it is not more "powerful" than traditional DX7 as this trick just compensates the lacks of 2 more OP.
harmonix variations waveformsPIC audio waves
are 4 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.
Tx81Z offers 8 algorithms combinations with frequency ratio or fixed frequency: the output is fed back to its input with 7 feedback levels, as general rule, high values feedback results in richer harmonic contents.
PERFORMANCE system manages 8 parts each with independent settings:
- analog mix level
- effect amount
- panning position
- stack mode Eg: 4 voices or 8 monophonic
- portamento with glide time
- analog out assignment.
The processor has some limits and cannot layer some particular algorithm combinations, furthermore Midi response has some freezes with data flows (depends also on the OS EPROM official from 1.0 to 1.6).
MICROTUNING 13 different tables: 11 ROM preset + 2 users for non-standard intonation including Equal, pure, major-minor, Vallotti and Werckmeister.
LFO there are 2 delayed modulators (frequency range from 0.007 Hz to 50 Hz):
- LFO1 to amplitude
LFO2 to pitch.
The modulators can be set to retrigger mode and features 4 shapes: saw, square, triangle and sample & hold.
ENVELOPE 4 EGs: each OP features 1 amplitude EG (4-segments) + 1 general shift.
Very simple Key tracking scale less sophisticated than previous DX line.
EFFECTS not a real DSP but faked simulated by a Midi notes trick reducing polyphony.
here are 3 kind of effects:
- delay: with possible pitch shift and adjustable feedback
- pan moving: stereophonic path with follow velocity or LFO from left to right or vice versa
- chords mode: handles up to 4 notes.
- 128 ROM patches (preset list)
32 RAM patches
24 RAM performances.
No external storage but full Sysex dump and edit by Midi or tape dump; note that MIDI Sysex strings are NOT compatible with 6OP DX line.
TX81Z BATTERY REPLACEMENT is quite easy but involves soldering a new lithium 3V CR-2032 (check picture below).
EDITOR there are many computer-based editors:
- Ctrlr (free)
TX81Z Programmer ($$)
VSTizer TX81Z ($$)
Atari: YSEDITOR , Steinberg synthwork (PIC) , caged 4 OP artist
MAX MSP : yamaha tx81z editor
RELATED FAMILY 4 OP:
VST PLUGIN / SAMPLED VERSION no official VST emulation, but some FM emulator (6 or 4 OP)
Mimì the synthcat with Tx81z and DX100