var n = Note.fromLatin('A4');  // single note
var freq = n.frequency();  // returns 440
var name = n.latin();  // returns "A"
var octave = n.octave();  // returns 4 

var cmaj = Note.fromLatin('C4E4G4');  // chord = array of notes
var freq = cmaj[0].frequency();  // returns 261.625...
var name = cmaj[0].latin();  // returns "C"
var octave = cmaj[0].octave();  // returns 4

var n = Note.fromLatin('C4');  // base note for scale
var majorScale = n.scale('major');  // scale = array of notes  

var fifth = Interval.fromName('fifth');  // define by name
var wholeStep = Interval.fromSemitones(2); // define by # of semitones

var c = Note.fromLatin('C3');

// use intervals to transpose notes
var d = c.add(wholeStep); 

// use intervals to define chords
var cmaj = c.add(['unison','major third','fifth']);