implemented instruments:

generate_arcoStrings,
generate_bassoon,
generate_clarinet,
generate_flute,
generate_horn,
generate_oboe,
generate_organ,
generate_saxophone,
generate_shepardsCarillon,
generate_shepardsOrgan,
generate_shepardsStrings,
generate_trumpet,
generate_tubularBells

src/Instruments/generate_horn.m

@@ -0,0 +1,41 @@
+function x = generate_horn(amplitude, frequency, phase, fs, duration, duty)
+% GENERATE_HORN: returns a matrix of sampled waveform similar to
+% a horn.
+
+% CONTRIBUTORS:
+% Brandon Roberts: Original author
+% MuseScore: Reference source for overtone information
+
+% DOCUMENTATION:
+% phase shift is in number of periods
+% fs is the sampling frequency: how many sample points per second
+% duration is time in seconds
+% duty does not apply for instruments
+   
+
+    % setup needed variables
+    n = fs * duration; % total data points
+    dt = 1 / fs; % space between samples
+    
+    % initialize template time scale
+    t = [1:n].*dt - phase;
+    f = frequency .* (1 + 0.0002 .* sin(4.*pi.*t)./t); %frequency vibrato
+    
+    % generate proper fundamental and overtones
+    x = (0.21707879.*amplitude .* sin(2.*pi.*f.*t)) ... %fundamental (first partial)
+        + (amplitude .* sin(4.*pi.*f.*t)) ... %second partial
+        + (0.234667056.*amplitude .* sin(6.*pi.*f.*t)) ... %third partial
+        + (0.088606568.*amplitude .* sin(8.*pi.*f.*t)) ... %fourth partial
+        + (0.0864485981.*amplitude .* sin(10.*pi.*f.*t)) ... %fifth partial
+        + (0.0275181724.*amplitude .* sin(12.*pi.*f.*t)) ... %sixth partial
+        + (0.0472968588.*amplitude .* sin(14.*pi.*f.*t)) ... %seventh partial
+        + (0.0246462876.*amplitude .* sin(16.*pi.*f.*t)) ... %eighth partial
+        + (0.00816134476.*amplitude .* sin(18.*pi.*f.*t)) ... %ninth partial
+        + (0.00691199377.*amplitude .* sin(20.*pi.*f.*t)) ... %tenth partial
+        + (0.00494872793.*amplitude .* sin(22.*pi.*f.*t)) ... %eleventh partial
+        + (0.0048026999.*amplitude .* sin(24.*pi.*f.*t)) ... %twelth partial
+        + (0.00335864486.*amplitude .* sin(26.*pi.*f.*t)) ... %thirteenth partial
+        + (0.00262850467.*amplitude .* sin(28.*pi.*f.*t)); %fourteenth partial
+    x = x .* (1 + 0.05 .* sin(2.*pi.*t)); %volume vibrato
+end
+