Unihiker TR-808 drum machine

In the realm of musical innovation, the Roland TR-808 stands as an enduring testament to timeless rhythm creation, having made its debut more than four decades ago. This iconic drum machine, with its groundbreaking capabilities, allowed musicians to break free from static patterns and sculpt their own rhythms. Notably, it boasted a distinctive, earth-shaking bass drum fashioned from a blend of a sine oscillator, a low-pass filter, a voltage-controlled amplifier, and even a dash of 'defective' solid-state transistors

The TR-808 found its place in the limelight through chart-toppers like Marvin Gaye's "Sexual Healing, ", Afrika Bambaataa- “Party Rock”, Talking Heads' "Psycho Killer, " “One more night” by Phil Collins and an entire album crafted by the Argentine musician Charly García. But the fervor surrounding this electronic machine doesn't stop there; there's even an entire documentary dedicated to its enduring influence.

Fast forward to today, and Roland has reintroduced a revamped version of the TR-808, while Behringer has also joined the ranks with their own take on this legendary drum machine.

In a homage to this iconic drum machine, using a Unihiker board, Python coding and 3d modelling, a very basic reincarnation of this beloved beat-making icon has come to life.

What is a Unihiker?

You can think of Unihiker as some sort of Raspberry Pi with Quad-Core ARM Cortex- A35 1.2GHz, an integrated 2.8 inches touchscreen, WiFi, buttons, accelerometer, buzzer, mic and light sensors. The Unihiker OS is Debian based, it comes preinstalled and ready to be used.

Parts required

1 x Unihiker

2 x rotation sensors(Unihiker is able to read analog pins)

1 x USB sound card (you can also use an external Bluetooth speaker)

Connect the 2 rotation sensors to P22 and P21 ports. Connect the USB sound card facing down. A red light will appear.

3d printed case

Case is not required. You can use the board with the silicone case

But if you want a better look for the TR-808 I have made this 3d printed case with Fusion 360. 2 parts, print with PLA. No support is required.

Software setup

Connect the USBC Cable from the PC to the Unihiker. Connect with Putty using SSH to 192.168.1.39

The user is root. The password is dfrobot

The Unihiker is used as the interface to control some functions of the excellent software beats made by Joel Strait.

To install beats just run:

$ gem install beats

Then run Alsamixer, select USB F6 and increase the volume.

Download the source code, samples and images from Github.

Now its time to load samples. The selected samples were obtained by Michael Fischer directly from a TR-808

Using SFTP with the same SSH credentials, upload the tr808.py code, sound and images to /home folder.

Run with

$ python tr808.py

Using the Unihiker TR808

With pot #1 you can change the tempo, which starts at 100 bpm. Turning it down will decrease 5 bpm and turning it up it will increase the bpm by 5.

With pot #2 you can change the “page” meaning changing from the first 8 to the second 8 of the same bar.

In each page there is a matrix with beats as the columns and sounds as the rows.

Sounds coding:

K kick
S snare
H closed hi hat
O open hi hat
C cymbal
B another bass kick

Clicking Start/Stop will create a beats.txt file, will execute beats software and finally play a.wav with the drum track. Those wavs could be used as a stand alone track and played in any Smartphone or computer.

Inside the code

The code presents a button matrix made with Unihiker library, which is based on Tkinter. Eachmatrix cell represents if asound is played at aspecific moment. There is also code to detect the potentiometers movement and adjust tempo and the matrix page number.

Whenever Start button is touched, the matrix is exported to a text file beats.txt, the text file is sent to Beats application and the wav file obtained from Beats application played through Unihiker Audio library.

Autoexecute the drum machine code at start up

$ crontab -e

Then add

@reboot /usr/bin/python /home/tr808.py>> log.txt

Demo

Where to go from here

More original sounds from the Roland TR808 could be used and also song parts (intro, verse, chorus) which are supported by Beats software. Another interesting feature could be a real time playing of the track being edited, which can be easily added with Python threads.

Complete source code is provided if anyone is interested to continue this project.

Jamming with the Unihiker TR-808

I have updated snare and tom sounds, uploaded some patterns to Github and recorded this little jam.

Maker counterculture talk

Contact for customizations and tech conferences

https://www.instagram.com/ronibandini/

https://twitter.com/RoniBandini