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Portable Tetra Setup

Portable Tetra Setup
« on: May 16, 2020, 04:38:27 AM »
The Tetra Portable


Image gallery / TLDR: https://imgur.com/a/Fcl3IoN

Around this time last year I was spending about 20-30 hours per week on busses and trains getting to and from uni. During this time I thought to make the most of those easily wasted hours, and began researching what I would need to do in order to take my Tetra with me. Learning the interface and creating patches and combos was a very fun way to pass the time. The front panel of the Tetra is not as bad for programming as it may seem. I generally prefer it to any software controllers, though I currently use my Mopho Keyboard for patch design.


The battery took the most time to figure out. In order to generate the 13-15V potential that the synth needs, I went with 4x Samsung 18650 cells in series. Each has a nominal voltage of 3.7V, making one 15V battery when all the cells are in series. You can use any capacity, but I went with the 3000mAh cells, and I have a battery life around 6-8 hours normally. I wired these to a BMS board so they charge evenly, and to prevent overdischarge.

I also sometimes use the battery to play my Mopho Keyboard on its own in random spots around the house and the backyard. It's really novel that I get to play with my synths while laying down in bed. :D


The case is made from a chocolate tin that we had in the house. I cut and glued in some foam pieces to hold the Tetra and battery in place, as well as a plastic support for the 1/4" to 3.5mm adaptor on the headphone output in order to take some strain off of the jack itself when inserting and removing the headphones.


Here are some things I would improve:
- More clearance needed on the case, as you can see some coating on the volume knob has rubbed off during transport.
- Customise the case with some paint or stickers, and make a more secure housing for the battery.
- Add in a one-octave MIDI keyboard to play chords and melodies in Program Mode.
- Add a switch to the power lead so it can stay plugged in while the synth is in the case.

« Last Edit: May 16, 2020, 04:40:44 AM by will.taylor »