Play some of Pachelbel's Canon
Mathematica, 212 152 139 135 bytes
{#~(s=##~SoundNote~41&amp;)~1&amp;/@LetterNumber@&quot;uursuursuikmnprsrrnprrfgikigifgiggkiggfdfdbdfgikggkikkmnikmnprsu&quot;,{14,18,21}~s~16}~Sound~18.5

Outputs a Sound object that plays Pachelbel's Canon in D when the Play button is pressed. The instrument is MIDI instrument #41 &quot;Violin&quot;.
The Audio
Click me!
Explanation
LetterNumber@&quot;uursuursuikmnprsrrnprrfgikigifgiggkiggfdfdbdfgikggkikkmnikmnprsu&quot;

Find the letter numbers of each character in the string (&quot;a&quot; -&gt; 1, &quot;b&quot; -&gt; 2, and so on), wrapped with a List. (This string represents Pachelbel's Canon in D)
#~(s=##~SoundNote~41&amp;)~1&amp;/@...

Set s to SoundNote function whose instrument is #41. Set the duration to 1 and map that function to each element in the List (thus making SoundNote primitive objects).
{14,18,21}~s~16

Make the last triad. (The duration 16 is there to make the last note 16 times longer--a whole note is sixteen times a sixteenth note.)
... ~Sound~18.5

Make a Sound object, 18.5 seconds long (because the tempo is 65 bpm [5 measures of 4/4 with tempo 65 bpm = approximately 18.5 seconds]).
126 byte version, non-competing
Sound[{(s=SoundNote)/@LetterNumber@&quot;uursuursuikmnprsrrnprrfgikigifgiggkiggfdfdbdfgikggkikkmnikmnprsu&quot;,{14,18,21}~s~16},240/13]

Non-competing because the output contains two sixteenth notes instead of an eighth note, and the separation is quite noticeable.