Do Temperature and Humidity Affect the Sound of Notes Played on a Church Organ
Note: This project requires testing a church pipe organ under different temperature and humidity conditions. Since it may be difficult to control the temperature and humidity levels immediately surrounding an organ during a fixed period of time, this experiment may need to be conducted on an organ at various phases for at least five months in order to capture different temperature and humidity levels produced by seasonal changes. Additionally, knowledge and use of an organ tuner or access to a professional organ tuner specialist are necessary to carry out this project.
To find out which temperature and humidity level is optimal for a church pipe organ to play a note as close to the standard pipe organ pitch frequency for that note as possible and to determine how much of a pitch frequency variance there is when the temperature changes by various degrees and when humidity changes by various percentages from the optimal playing temperature and humidity level.
Many church pipe organs are very old and were built at a time when churches were not heated to the standards that they are today. Newer churches have modern heating and cooling systems which have created new issues concerning heat and dryness. Changes in temperature and humidity levels are not only damaging for a church pipe organ but may also affect the consistency of the sound quality produced by the organ. Optimal temperature and humidity levels for a traditional pipe organ to produce the correct pitch can be determined, as can the amount of note frequency variance caused by changes in temperature and humidity.
- traditional church pipe organ (not electronic)
- pipe organ tuning fork or tuning machine
- digital thermometer
- digital hygrometer
The two principal stops on a pipe organ that form the tonal basis for the entire scale of the instrument will be used. Temperature and humidity levels will be read with the thermometer and hygrometer at each visit, and the same notes will be played each time at the various octaves to determine the frequency of the notes with the tuner. The frequency readings of the notes will be compared against the true pitch frequencies for these notes. When the true pitch frequency of the notes is reached, the temperature and humidity levels present at that time will be recorded and used as the optimal temperature and humidity level from which all other temperatures, humidity levels, and frequency readings will be compared. Finally, the amount of variance that exists when the temperature changes by various degrees and when the humidity changes by various percentages will be recorded.
- Make arrangements with a church that has a traditional pipe organ (with a manual console and physical stops) to test and observe the temperatures, humidity levels, and pitch frequencies on the organ over a period of at least 5 months (or less if the temperature and humidity varies greatly in a shorter period of time). Additionally, make arrangements to work with a professional pipe organ tuner who may be able to mentor you in recording the frequencies of the notes played on the organ, unless you know how to measure note frequencies on an organ tuner.
- Use the two principal stops on a pipe organ that form the tonal basis for the entire scale of the instrument (other stops can be used if desired).
- Take the temperature in the pipe chamber of the organ with the digital thermometer and take the humidity level with the digital hygrometer. Record your readings for both.
- With the help of your mentor (if you have one) or through your own knowledge and experience with a tuning fork or tuning machine, play the note C at various octaves and record the frequencies for each C note played. Note how far off the true pitch frequency each note is according to the tuning fork or tuning machine. Record the frequencies for the note at each octave. You can label each note played as C1, C2, C3, C4 (middle C), and so on. Repeat with other notes at different octaves. If at any time you achieve the closest pitch frequency reading that a note should be at, remember to take note of the temperature and humidity levels present when that reading was recorded.
- Repeat steps 1–4 at various temperature and humidity levels to achieve various readings for temperature, humidity, and frequency.
- Analyze your data and find the variance that exists between the true pitch frequency for a note and the frequencies you recorded at various temperatures.
- Were you able to test the organ at a full range of temperatures and humidity levels? If so, at what temperature and humidity level was the organ most capable of producing frequencies that were as close as possible to the true pitch frequencies of notes played?
- How much variance existed in the frequency of the notes played from the true pitch frequency of the notes at different temperatures and humidity levels?
Warning is hereby given that not all Project Ideas are appropriate for all individuals or in all circumstances. Implementation of any Science Project Idea should be undertaken only in appropriate settings and with appropriate parental or other supervision. Reading and following the safety precautions of all materials used in a project is the sole responsibility of each individual. For further information, consult your state’s handbook of Science Safety.