TX816 Controller: Build Diary (last update 2026-01-23)

Here the short minutes about current builds and when you can expect your device. Newest posts are at the bottom.

2025-09-03

Controller #2 is finished, reserved for Matti on May 25.

#1 is my own device that you can see in my YT videos. Next build actually will be a VL1 controller for Greg, reserved on July 25. Then comes controller #3 for Robert.

2025-09-15

Here the full set of used PCBs.

• PCB for the encoders and OLED displays, two layers of copper
• LEDs and push buttons
• redesigned MIDI I/O plus audio preamplifier
• Arduino DUE (80Mhz version of the Arduino Mega.
• TFT display with SD card

All these components will be manually wire-wrapped with around 80 cables

I received a batch of warm white LEDs, the next devices will have white lights instead of red.

2025-10-01

Now finished the VL1 controller for Greg. The new LEDs are quite nice, remind me to small light bulbs.

2025-10-19

Finishing #3 for Robert, here all connections wire-wrapped.

2025-10-30

Starting devices #4 and #5 for Scott and Deaton

Firmware reworked:

• automatically sending MIDI panic, when Notes On detected while switching modules.
• File > selectDir starting at 101 if in single program mode, else at 100 (multi directory)
• Edited cc7 Volumes of all modules are also stored in the multi file.

2025-11-15

The two front panels ready for assembly into the case and final wiring.

2025-12-10

… device #4 finished and sent by DHL Express. Continue with #5.

2025-12-14

Device #5 finished. Making final tests to ship before Christmas. Next devices #6 and #7 are planned for Preston and Stefan.

Firmware extended by a new “Oberheim” mode: Random.

2026-01-04

I’ve started implementing MIDI MPE as an additional “Oberheim” mode. Each module will be assigned its own MIDI channel, resulting in an eight‑voice MPE‑capable FM synthesizer. This will allow me to play it directly from the Osmose. The X‑axis controls Pitch Bend, the Y‑axis controls the Modulation Wheel, and the Z‑axis is mapped to Channel Aftertouch.

2026-01-11

Device #6 finished. Will go to Ake instead of Preston, as I forgot to retrofit his special request of having red LEDs instead of white. Preston will get #7, Stefan #8, Ryan #9, David V. #10. Then David J. will get his VL1 controller.

Reworked firmware to stabilize the recording VU meter by moving average.

Stopped MPE implementation by now, it turned out that the mass of X,Y,Z messages are choking the MIDI messages easily. Have to invest more on prioritisation strategies.

2026-01-25

Firmware modified with following features. User Manual reworked.

• LED brightness is now adjustable
• Performance settings can now be stored and is automatically read at boot time
• PurgeDirectory has been changed by an additional prompt for confirmation
• Backup and Restore now working

2026-01-26

Finished #7 with red LEDs. Next weekend I’ll start the next one.