Some Mozzi audio experiments

Using my own samples with Mozzi

Have finally cracked getting my own samples into Mozzi. The sound clips need to be VERY short (around 0.5 seconds) or they are too big for the Nano. I also tried mono to see if that saved space, but then there was no sound at all. I really raised the volume of this sample and the clipping isn’t too noticeable compared to the previously-encoded version , as it clips because of the processing anyway.

Here’s the code:

/*  Example of playing a sampled sound,
    using Mozzi sonification library.
  
    Demonstrates one-shot samples scheduled
    with EventDelay.
  
    Circuit: Audio output on digital pin 9 on a Uno or similar, or
    DAC/A14 on Teensy 3.1, or 
    check the README or http://sensorium.github.com/Mozzi/
  
    Mozzi help/discussion/announcements:
    https://groups.google.com/forum/#!forum/mozzi-users
  
    Tim Barrass 2012, CC by-nc-sa.
*/

#include <MozziGuts.h>
#include <Sample.h> // Sample template
#include <samples/alienwave.h>
#include <EventDelay.h>

#define CONTROL_RATE 64

// use: Sample <table_size, update_rate> SampleName (wavetable)
Sample <alienwave_NUM_CELLS, AUDIO_RATE> aSample(alienwave_DATA);

// for scheduling sample start
EventDelay kTriggerDelay;

void setup(){
  startMozzi(CONTROL_RATE);
  aSample.setFreq((float) alienwave_SAMPLERATE / (float) alienwave_NUM_CELLS); // play at the speed it was recorded
  kTriggerDelay.set(1500); // 1500 msec countdown, within resolution of CONTROL_RATE
}


void updateControl(){
  if(kTriggerDelay.ready()){
    aSample.start();
    kTriggerDelay.start();
  }
}


int updateAudio(){
  return (int) aSample.next();
}


void loop(){
  audioHook();
}

With thanks to Tim Barass and his very helpful forum for help getting this working.

Taking shape

The latest version of Space Rock #4, sanded and with the circuit board and powerbank holder printed for inside. Also shown is a version of Space Rock #1 printed in sections at 280mm wide, and coated with XTC 3D as a test as this print has lots of flaws – not least because the filament snapped just before finishing printing the front section, so I had to do a patch repair. Interesting to see how smooth this sands down.