Digital Synth VRA8-M for Arduino Uno
by risgk in Circuits > Arduino
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Digital Synth VRA8-M for Arduino Uno
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Made by ISGK Instruments
Concept
- Monophonic Synthesizer (MIDI Sound Module) for Arduino Uno
Features
- Serial MIDI In (38400 bps), PWM Audio Out (Pin 6), PWM Rate: 62500 Hz
- Sampling Rate: 15625 Hz, Bit Depth: 8 bits
Demo Audio
Notes
- Exhibited in Maker Faire Tokyo 2015
Wiring
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Required Hardware
- Arduino Uno
- 3.5 mm Audio Jack (or Speaker)
- 330 (150 or more) ohm Resistor
- Wires
Wiring
- Audio Jack L or R (or Speaker +) ---- Resistor ---- Arduino Uno Digital Pin 6
- Audio Jack GND (or Speaker -) ---- Arduino Uno GND Pin
- PC ----[USB Cable]---- Arduino Uno
Additional Notes
- We recommend adding a RC filter circuit to reduce PWM ripples
- A cutoff frequency 10.6 kHz (R: 150 ohm, C: 0.1 uF) works well
- Ref. http://sim.okawa-denshi.jp/en/CRlowkeisan.htm
- Ref. http://sim.okawa-denshi.jp/en/CRlowkeisan.htm
Software Installation
Start Synthesizer
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Explanation for Windows
- Write DigitalSynthVRA8M.ino to Arduino Uno and quit Arduino IDE.
- Start loopMIDI.
- Start hairless-midiserial.exe (Hairless MIDI<->Serial Bridge).
- Set [File] > [Preferences] > [Baud rate] to 38400 bps.
- Select Arduino Uno (COM*) on Serial Port.
- Select loopMIDI Port on MIDI In.
- Open vra8-m-ctrl.html (VRA8-M CTRL) with Google Chrome.
- Select loopMIDI Port on MIDI OUT.
- Select a MIDI controller on MIDI IN (if you have it).
- Click (or touch) the Software Keyboard, and you can hear the sound.