/* Detect the frequency of music notes, by Colin Duffy This example repeatedly plays a guitar note (output to the DAC pin) and prints an analysis of the frequency to the Arduino Serial Monitor https://forum.pjrc.com/threads/32252-Different-Range-FFT-Algorithm/page2 https://github.com/duff2013/AudioTuner */ /* C C# D Eb E F F# G G# A Bb B 0 16.35 17.32 18.35 19.45 20.60 21.83 23.12 24.50 25.96 27.50 29.14 30.87 1 32.70 34.65 36.71 38.89 41.20 43.65 46.25 49.00 51.91 55.00 58.27 61.74 2 65.41 69.30 73.42 77.78 82.41 87.31 92.50 98.00 103.8 110.0 116.5 123.5 3 130.8 138.6 146.8 155.6 164.8 174.6 185.0 196.0 207.7 220.0 233.1 246.9 4 261.6 277.2 293.7 311.1 329.6 349.2 370.0 392.0 415.3 440.0 466.2 493.9 5 523.3 554.4 587.3 622.3 659.3 698.5 740.0 784.0 830.6 880.0 932.3 987.8 6 1047 1109 1175 1245 1319 1397 1480 1568 1661 1760 1865 1976 7 2093 2217 2349 2489 2637 2794 2960 3136 3322 3520 3729 3951 8 4186 4435 4699 4978 5274 5588 5920 6272 6645 7040 7459 7902 Guitar strings are E2=82.41Hz, A2=110Hz, D3=146.8Hz, G3=196Hz, B3=246.9Hz, E4=329.6Hz Bass strings are (5th string) B0=30.87Hz, (4th string) E1=41.20Hz, A1=55Hz, D2=73.42Hz, G2=98Hz This example tests the yin algorithm with actual notes from nylon string guitar recorded as wav format at 16B @ 44100 samples/sec. Since the decay of the notes will be longer than what the teensy can store in flash these notes are truncated to ~120,000B or about 1/2 of the whole signal. */ #include #include #include #include #include //--------------------------------------------------------------------------------------- #include "guitar_e2_note.h" #include "guitar_a2_note.h" #include "guitar_d3_note.h" #include "guitar_g3_note.h" #include "guitar_b3_note.h" #include "guitar_e4_note.h" #include "tuba_1.h" #include "tuba_2.h" #include "tuba_3.h" #include "tuba_4.h" #include "tuba_5.h" //--------------------------------------------------------------------------------------- AudioAnalyzeNoteFrequency notefreq; AudioOutputAnalog dac; AudioPlayMemory wav_note; AudioMixer4 mixer; //--------------------------------------------------------------------------------------- AudioConnection patchCord0(wav_note, 0, mixer, 0); AudioConnection patchCord1(mixer, 0, notefreq, 0); AudioConnection patchCord2(mixer, 0, dac, 0); //--------------------------------------------------------------------------------------- IntervalTimer playNoteTimer; void playNote(void) { if (!wav_note.isPlaying()) { // Uncomment one of these sounds to test notefreq wav_note.play(guitar_e2_note); //wav_note.play(guitar_a2_note); //wav_note.play(guitar_d3_note); //wav_note.play(guitar_g3_note); //wav_note.play(guitar_b3_note); //wav_note.play(guitar_e4_note); //wav_note.play(tuba_1); //wav_note.play(tuba_2); //wav_note.play(tuba_3); //wav_note.play(tuba_4); //wav_note.play(tuba_5); digitalWriteFast(LED_BUILTIN, !digitalReadFast(LED_BUILTIN)); } } //--------------------------------------------------------------------------------------- void setup() { AudioMemory(30); /* * Initialize the yin algorithm's absolute * threshold, this is good number. */ notefreq.begin(.15); pinMode(LED_BUILTIN, OUTPUT); // Audio library isr allways gets priority playNoteTimer.priority(144); playNoteTimer.begin(playNote, 1000); } void loop() { // read back fundamental frequency if (notefreq.available()) { float note = notefreq.read(); float prob = notefreq.probability(); Serial.printf("Note: %3.2f | Probability: %.2f\n", note, prob); } }