Blog Posts

Chip Audette and the folks at Tympan has developed a fully open source hearing aid development platform.

Hearing aid technology has been closed technology with access only available to those working in the industry and Chip set out to change that.  What began as an experimental project has now become Tympan, an open source hearing aid development platform.

The Tympan platform uses a Teensy 3.6 and the Digital Signal Processing (DSP) capabilities of the Teensy Audio Library to implement dynamic range compression – amplifying quieter sounds while not making louder sounds any louder.  Chip has a great explanation of the need for dynamic range compression in this blog post.  He follows it up with details on how he implemented it in this blog post.

The Tympan units are affordable devices that allows users to program and customize their own hardware to best suit their hearing needs without having to go to a technician each time an adjustment is needed.

The Tympan hearing aids are OSHWA Certified.  Code, schematics and KiCad files are available on GitHub.

Wyatt Olsen built an incredible electronic drum set that that is fully portable and customizable.

Looking to get back to playing drums, Wyatt decided to create Dum Master, an electronic drum set.  The first rev was functional but had a few problems such as difficulty in getting accurate velocity sensing and the need for a separate computer to play the sounds.  Notable improvements with Rev 2 of the project include using peak detection hardware and using a Teensy with an Audio Shield for playback.

Additional details can be found on the Drum Master website.

Code for the project has been published on GitHub.

Delta Space Systems has developed a flight computer for launching rockets into high altitudes.

The Omega flight computer features 2 pyro channels, 2 servo outputs for thrust vector control, data logging, altitude measurements, and a gyroscope.  This latest version of their flight computer upgrades from using a Teensy 3.2 to a Teensy 3.5.  The increased processing power allows for additional data logging to make more accurate TVC (Thrust Vector Control) movements.  They were also able to eliminate the SD socket and flash chip from the design which contributed to a significant weight reduction.

UHF made TSynth, an awesome sounding four note polyphonic synthesizer.

Inspired by the Teensy-Synth series by Notes & Volts, UHF set out to make his own synthesizer using a Teensy 3.6, Audio Shield, and the Audio Library.

 

This synth is packed with features including four voice polyphony with two oscillators per voice.  Check out the forum post for a full list of features on this incredible project.

 

Mohit Bhoite made Bubble Punk, a nifty little sculpture to measure temperature and humidity.

Along with a Teensy-LC, the sculpture uses an Adafruit SHT32-D sensor breakout board, a vintage HP5052 7415 7 segment display, and a WS2812B LED to light it up.

 

FRDM4236 (Trainder4EDU) has created an expansion board for Teensy 4.0, similar to Dean’s, but providing all the extra signals & features in a Teensy 3.6-list form factor.

The Trainer4Edu website has detailed information on the board as well as build instructions for you to build your own.

 

 

 

 

 

 

Dean Blackketter created an add-on board which makes Teensy 4.0’s bottom-side pads available as a second row of normal pins!

It attaches underneath with castellated holes to solder to Teensy 4.0’s bottom-side pads.

If you’ve wanted a way to plug Teensy 4.0 into a sturdy through-hole socket and have access to all the signals, this looks like a really nice way to gain easy access to those bottom-side pads.

Dean shared this PCB on OSH Park and the Kicad files on Github.  Much more detail is available on Dean’s forum post and conversation which follows.

Nick Anderson created this amazing light & sound show for Halloween.

The lighting and sound was composed with the Vixen3 software.  The actual show runs using the Falcon Pi Player software on a Raspberry Pi 3, which transmits to a Teensy 3.2 and OctoWS2811 board to drive 2850 LEDs.  Nick published his source code on github.

 

Sandro Grassia made Lilla, an neat, open source,  polyphonic MIDI expander.

Lilla’s controls features 12 rotary encoders and 8 pushbuttons and includes MIDI in, MIDI thru, and stereo out.  It can read files from and SD card as well as internal memory.

Additional details as well as code for the project can be found on GitHub.

 

Arvind Singh (forum user vindar) made an amazing acoustic levitator.

An acoustic levitator uses sound waves to levitate small objects, and until a few years ago were expensive to construct using Langevin horns that required tight tolerances and operate at high voltages.  Asier Marzo from Bristol University published a paper demonstrating how an acoustic levitator can be constructed from off the shelf parts and run on low-voltage.

Arvind built a levitator from an Instructible project based on an Arduino Nano, then decided to improve upon it by building one with a Teensy 3.2.  The processing power and memort of the Teensy 3.2 allowed for additional options to be added such as a TFT display and a joystick.

The casing was 3D printed using wood PLA then stained and varnished making for a beautiful device.

Code, schematics, and STL files are available on Git Hub.