MATRIXSYNTH: MoonBox

Raspberry Pi Synthesizer - "My Stry Sulfat" jam Published on Aug 23, 2015 cube48

This is the MoonBox posted here. Two videos of it in action. Info and pics further below.

"One pattern twiddle on MoonBox - SunVox powered DIY Raspberry Pi 2 synth.

More info about the MoonBox can be found on official SunVox forum:
http://www.warmplace.ru/forum/viewtopic.php?f=16&t=3733"

MoonBox - DIY Raspberry Pi 2 Synthesizer powered by SunVox Virtual Modular Music Studio

Published on Aug 6, 2015

"No music to listen here. Just my low or no playing skills. This is rather about demoing some of the Analog Generator patches of SunVox. First part shows some of the default template sounds, second shows a bit of knob twiddling and a few quick patches I made from the simple 'analog' template I prepared and mapped to 16 knobs of the MoonBox. But SunVox can do a lot more!"

via the forum:

"Let me introduce you the SunVox powered Raspberry Pi 2 standalone synthesizer. The idea was to have dedicated machine/box with SunVox including some knobs. Like a real synth. This vision was maturing in my head for some time but the trigger were NightRadio's comments about upcoming MIDI CC support in 1.9 before the beta was released. I've collected all the building blocks but I was still missing the enclosure. For some time I was designing a custom made 'ponoko' box to be laser-cut. But then I got too impatient and searched through available stuff at home. Wine box for the win :-D

The synth is so far consisting of these bits:

Raspberry Pi 2 B
IQ Audio PiDAC+
5.0" 40-pin TFT Display - 800x480 with Touchscreen
TFP401 HDMI/DVI Decoder to 40-Pin TTL Breakout - With Touch
40-pin FPC Extension Board + 200mm Cable
Guts of the old Evolution UC16 USB MIDI controller (only the main and pot control board)
A bunch of nuts, bolts, spacers and wooden wine box.

Further improvements are still on the todo list:
* jack outputs for L, R and headphones mounted to the rear side of the box
* 5-DIN MIDI I/O connectors on the rear side - realized via USB<>MIDI cable
* some USB ports exposed on the rear side - mounting small USB hub
* power switch + connector on the rear side
* HW volume encoder for PiDAC+ on the top side
* main out GPIO LED volume indicators (this is optional)
* final paint and design tuning

A few notes to the design. RasPi needs to be powered with 2000 mAh adapter to feed all the peripherals. PiDAC+ gives you really powerful and clean sound, also for hungrier headphones. RasPi 2 with stock Raspian OS with ALSA (no realtime kernel, no JACKD, no performance tweaks except disabled CPU power-saving) is able to play decent SunVox synths with 11ms latency without compromising the sound - not ideal but already playable. Lowering the buffer to 5ms introduces occasional noise cracks. I'll try to play with the OS tweaks later but I might stick to ALSA as it is supported by PiDAC+ volume encoder routine. Display is connected via HDMI and USB cables (I'm waiting for shorter and flat HDMI cable). HDMI delivers the image, USB powers the display and touch board. UC16 MIDI controller is connected also via USB (not on the photos above). The only connection hack will be soldering wires to PiDAC+ so I get the normal jack connectors. Current cinch connectors are fine but the placement is not ideal. I want to keep all the 'internal' connections inside the box and expose only the stuff that has to interface outer world and if I would expose the cinch through the rear side, also the HDMI cable would stick out and then coming back which is not desired. The front panel will need some locking or support mechanism, ideally in various angles. The whole thing reminds the Roland's 'Plug-Out' system. You prepare the synth/composition/patch on PC/tablet/phone and then load it to the box if you don't want to mess around with the small screen. But it's actually nicely usable in the box as well as you all know from your own SunVox-on-phone experience. Sun bless Alex for his perfect and scalable UI. RasPi is configured to boot and load up the SunVox automatically, opening the last session. Like a real synth :)

Do you guys have any cool name ideas for the synth? Right now I call it simply SunSynth but that's too obvious. Some link to the SunVox would be cool but maybe something more esoteric :)

Alex, THANK YOU for such a great piece of software! Btw, I hope you don't mind if I put the SunVox logo on the box when it's finished?.."