Fully Built 12 notes polyphonic ElectroTechnique TSynth V1.3


Shipping to United States: Free

Note : The shiping is included in the price and done in "Priority" mode & Tracked.

You'll get a TSynth V1.3 fully built & tested.

Available in red, blue, black, yellow or purple version.

I can customise the color of the LEDs, of the caps.

You'll get also a USB cable & the printed user manual.

The TSynth come with 63 preset patches + 8 new patches I made.

The final prodcut size is about 320mm x 150mm x50mm

It is safe RoHs compliant (Lead Free).


The TSynth is a little beast made by an enthusiast electronic guy under the name of ElectroTechnique as an open source low cost DIY project. This is an impressive polyphonic machine at a remarkable price !

The new firmware offers 12 voice polyphony with 2 oscillators per voice, individual LFOs and pitch envelopes, lots of pulse width modulation and noise generation. The state variable filter has its own envelope and LFO. You can stack the oscillators into dynamic or chord unison and there’s plenty of cross-modulation on offer. At the end of the chain is a stereo ensemble chorus effect. It comes with a bunch of presets and you can save and recall your own.

SPECS (Firmware 2.20) :

Oscillators :

- 12 voice polyphony (last note priority), two oscillators per voice, velocity sensitive, detunable with +/- 2 octaves range, Sine/Sample & Hold (like tuned noise)/Square/Sawtooth/Ramp/PWM/Var Triangle/User waveforms and level. Square, Sawtooth and Pulse waves are band-limited.
- Pulse Width/Var Triangle can be set for each oscillator with PWM by dedicated LFO or from the filter envelope
- Pink or white noise level
- Dedicated LFO for pitch mod (can be retriggered by note on), Sine/Triangle/Sawtooth/Ramp/Square/S&H waveforms
- Pitch can be modulated by filter envelope (+/-)
- Oscillator FX - XOR creates lots of harmonics with certain waveforms and X Mod ‘Cross Modulation’ bell-like sounds.
- Dynamic Unison with all 24 oscillators detunable from each other - one, two, three or four notes can be played with oscillators distributed among them
- Chord Unison with all oscillators playing a chord selected from detune control - major, minor, diminshed…
- Monophonic mode - first, last, highest, lowest note priorities.
- Polyphonic Glide with variable time

Filter :

- State variable 12dB filter (SVF) with continuous mix between LP and HP (provides notch filter) and BP
- Cutoff freq and resonance
- Cutoff can be modulated by dedicated exponential ADSR envelope (+/-), dedicated LFO
- LFO has same waveforms as pitch LFO (can be retriggered by note on) and rate can be set to match MIDI clock (tempo) with variable time division (1,3/4,1/2,1/4,1/8…)

Amplifier :

- Dedicated ADSR envelope with exponential attack (adjustable), decay and release stages
- Volume
- Effect amount and mix - currently for stereo ensemble chorus rate and mix but could be set up to allow choices in Settings menu

Patch & Program Buttons

- Encoder with button for data entry, Back button for menu navigation
- Save and Delete buttons for storing patches
- Holding Settings initialises the current patch to match the panel controls. Holding the Save button takes you into a patch deletion page.
- Settings Menu - Velocity curve, Pitch Bend and Mod Wheel range, VU Meter, oscilloscope display, bass enhance, MIDI In, Thru and Out options.


- USB HOST MIDI Class Compliant (direct connection to MIDI controller, no PC needed)
- USB Client MIDI In from PC
- MIDI In 5 pin DIN
- MIDI Thru/Out 5 pin DIN - configurable as a thru with filtering options or an out

Audio :

SGTL5000 Audio Shield 16 bit, 44.1 kHz Stereo out
USB Audio in/out—appears as 16 bit, 44.1 kHz audio interface on PC


What's new in V1.3 ?

- The 6N138 optocoupler is now a 6N137. JLCPCB ran out of the previous (half of them went on TSynths) and they have plenty of 6N137s.

- MIDI thru is now a software thru/out with filtering options. V1.2 PCBs can use this if they are simply modified by cutting a trace and soldering a wire.

- The display SCK line has been re-routed with a series 100ohm resistor to get rid of noise coming through the analogue audio at high volumes.

- The display backlight is connected to pin 6 of the T4.1, so it could be turned off or PWM dimmed. This is in anticipation of a possible soft on/off switch or power saving mode, which requires the display backlight to turn off. Again, V1.2 PCBs can easily be modified by users, for this.


You can find detailed information about the project at https://electrotechnique.cc/ or on the GitHub page of the project https://github.com/ElectroTechnique/TSynth-Teensy4.1


Please note that this is a low cost, low volume DIY project where the build quality may reflect the low price, meaning there may be minor cosmetic inaccuracies / imperfections! Cosmetic defects (thin scratches, dents or similar defects that do not affect the basic functionality of the product) are not valid grounds for a refund complaint and will not be considered. Please do not order if you do not agree !

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