polynominal logo
Synthesizers Drum machines Samplers Effects 8-16bits+ toys HOME

Yamaha TX81Z



yamaha tx81z

audio demo trend price : 80-120€
manual factory patch demo video sample comments

Yamaha Tx81Z - Multi Timbral FM tone generator (1987)  

A budget rack featuring a FM variation of traditional DX 6OP.

Budget spin-off from the famous DX-7 FM synthesis, however there are some interesting technical improvement.

yamaha tx81z panel
tx81z technical data

info RACK (weight: 3.4 kg)
Main panel features a 2 x 16 lines display and 11 push buttons.

Back panel terminal connectors:
- main outputs
- aux outputs
- Midi interface
- tape interface for data storage.

Front panel terminal connectors:
- headphones out

edit VOICE
CPU is a HD63803XP Hitachi manages 8 digital voices.
The previous DX synthesis was based on a 6 operators system with just pure sinewave and 32 combinations algorithms. The internal TX81Z IC chip YM2414B has only 4 OP and 8 combinations, on the other hand if offers 8 different waveforms including the standard DX Sinusoidal plus 7 computer-generated harmonics variations with partials and fundamentals fixed settings.


there 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 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.

data 4op

system manages 8 parts each with independent settings:
- mix level
- Midi channel
- effect amount
- pan position
- stack mode Eg: 4 voices or 8 monos
- portamento with glide time
- analog out assignment
The processor has some limits and cannot layer some particular algorithm combinations, and Midi response has some freezes with data flows (depends also on the OS EPROM official from 1.0 to 1.6)

lfo LFO
there are 2 delayed modulators (frequency range from 0.007Hz to 50Hz)
- LFO amplitude
- LFO pitch
The modulators can be set to retrigger mode and features 4 shapes: saw, square, triangle and sample & hold.

there are 4 EG in total: each OP features 1 amplitude EG (4-segments) + a general shift. Very simple Key tracking scale less sophisticated than previous DX line.

effect EFFECTS
not a real DSP but faked simulated by Midi notes tricks reducing the (tiny) polyphony.
There are 3 effect families:
-dDelay: 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 4 notes

memroy MEMORY
- 128 ROM payches
- 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.

cem curtis 3372
battery soldered 3V Cr-2032

cem curtis 3372


scales MICROTUNE the 4 OP structures has 13 different microtuning tables: 11 ROM preset + 2 users for non-standard intonation including Equal, pure, major-minor, Vallotti and Werckmeister.

tx81z demo

EDITOR there are many computer-based editors:
PC: Ctrlr (free) Midiquest ($$) , noize ($$) , TX81Z Programmer ($$) VSTizer TX81Z ($$)
Atari ST: YSEDITOR , Steinberg synthwork , caged 4 OP artist
MAX MSP : yamaha tx81z editor

tx81z demo
Atari St classic from steinberg

txz81z editor



yamaha dx9 Yamaha dx9 (1983) first 4 OP model. Quite incompatible to other 4 Op DX line

yamaha dx21 Yamaha dx21 (1985) : real first started of the series with bitimbric layer with chorus and pitch EG

dx100 Yamaha dx100 (1985) : same as dx21 with minikeyss (cutteee!)

dx27 Yamaha dx27 (1985) : simplier dx21 version with 1 part, also a S version with internal speakers

fb01 Yamaha Fb01 (1986) simple module

yamaha dx11 Yamaha Dx11 (19986) : more or less the Tx81z version with 8 harmonic waves

yamaha ys200 Yamaha Ys200 (1988) : consumer 4 Op version with sequencer. Also:
- Ys100 without sequencer and
- Tq5 is a laptop version
-B200 with internal speakers
yamaha-v50 Yamaha V50 (1989): Boosted Ys200, top notch of 4 op series, with sequencer, drum machine, sequencer..


scales VST EMULATION there is no official VST emulation, however the FMHeaven (PC/MAC commercial) imports both DX7 and Tx81z patches. Click on the relative pic for an audio demo.

tx81z demo


tx81z demo

effet Soundcloud TX81Z

demo1 demo2 demo2


TX81Z Trackdriver Presets Yamaha TX81z Yamaha TX81Z Performance Mode
Trackdriver Presets demo1 Performance Mode




Free Tx81z sample pack!

sample download

a little gift for you!
Free SF2 65mb samples

original scan



original scan



left side rack side logo printed


- cheap
- sinewave variations


- edit
- midi buffer
- polyphony


" aggressive digital sound at low price! needs a lot of time for programming and the awful interface can discourage good will---
Power for few bucks!."




polynominal logo
      For sale Comment Contact
Synthesizers Drum machines Samplers Effects 8-16bits+ toys HOME

all snapshots, sounds, texts copyright Polynominal.com / Eric Pochesci

yamaha tx81z 4 out of 5 based on 33 ratings. price €80