Vocal processing with accompaniment music input

A time-aligned audio system for harmony generation, comprising:

• a digital signal processor configured to:
• receive a melody audio signal produced by a singer,
• detect melody notes within the melody audio signal,
• determine whether the melody notes include one or more errors,
• produce a harmony signal harmonized to the melody notes and an accompaniment audio signal while ignoring the errors,
• transmit the harmony signal to a loudspeaker,
• store the melody audio signal in memory until the harmony signal has been produced, and
• transmit a version of the melody audio signal to the loudspeaker substantially simultaneously with the harmony signal.

A method of generating a time-aligned, harmonized musical signal, comprising:

• determining melody notes within a melody audio signal,
• determining chords within an accompaniment audio signal,
• analyzing at least one of the audio signals to identify errors,
• producing a harmony signal harmonized only to the melody notes and the chords which do not include the identified errors,
• storing the melody audio signal and the accompaniment audio signal until the harmony signal has been produced, and
• transmitting a version of the melody audio signal, a version of the accompaniment audio signal and the harmony signal to a loudspeaker substantially simultaneously.