Date of Defense



Electrical and Computer Engineering


Students of both instrumental and vocal music constantly face the challenge of maintaining good intonation. Good intonation is playing or singing exactly on pitch. An instrument called an"Out- Of-Tune Analyzer" was designed, built and tested. This instrument provides continuous audio and visual feedback to a user on his/her intonation in real time as the musical piece is being performed. The performer can select frequency tolerance bands, scales, and either a"Continuous" feedback mode or a "Wrong Only" feedback mode.

The device consist of a microphone, a microcontroller, a liquid-crystal display (LCD), a keypad, electronic amplifiers and various lights. It will alert the performer when he/she strays from the exact musical frequencies during a musical performance.

This device use a microphone to pick-up the music being played. The musical signal is amplified, converted to digital signal and fed into a 68HC11 microcontroller. The period of the musical signal is measured by the microcontroller. An LCD and keypad enable the student to select mode, frequency tolerance, scale, displaying errors and calibration. A software period look-up table is generated according to the player selections. If the signal is out of frequency tolerance, the microcontroller may or may not generate an exact tone to the speaker depending on which "Mode" is selected. For a "Continuous" feedback mode, it always generates an exact tone; for a "Wrong Only" mode, it generates a correct note only if the music is out of tune.

This device was designed to be a training aid to shorten the learning time for music students. It is not intended to substitute or replace the role of a music instructor. It is worthwhile to note that the project is not a duplicate of any product available in the market. It should not be confused with chromatic tuner or the like. This project has received "WMU Undergraduate Research and Creative Activities Award" and "Seibert Research Travel Award". Both awards are from the Lee Honors College.

Access Setting

Honors Thesis-Campus Only