d. You’ve designed one of the ranks of pipes within the organ using a metal alloy consisting of a mixture of tin and copper. The customer decides (at the last minute) that they like the sound of stainless steel pipes for these ranks better. How do you anticipate this change in pipe material will impact the sound produced by the organ?
i. The fundamental frequencies will remain unchanged but the harmonics will be different
ii. The fundamental frequencies will be higher while the harmonics will remain unchanged
iii. No change in fundamental or harmonic frequencies
I bet your teacher wants answer iii. However, I also bet he has never heard E. Power Biggs recordings on a series of German organs, of various materials. yes, they sound different.
See this:
http://www.albany.edu/piporg-l/pipemet.html
In order to anticipate how the change in pipe material will impact the sound produced by the organ, we need to understand the properties of the different materials involved.
Tin and copper, which make up the metal alloy initially chosen, have specific acoustic properties that contribute to the sound of organ pipes. Stainless steel, on the other hand, has different acoustic characteristics.
When it comes to pipe materials, the primary factors that affect the sound are the density and stiffness of the material. Tin and copper have specific densities and stiffness that determine their acoustic behavior. Stainless steel, being a different material, will have its own density and stiffness properties.
Given that the customer prefers the sound of the stainless steel pipes, we can anticipate some changes in the sound produced by the organ. Here are the possible outcomes:
i. The fundamental frequencies will remain unchanged, but the harmonics will be different: Fundamental frequency refers to the base pitch produced by the pipe, while harmonics are additional frequencies that resonate alongside the fundamental frequency. If the customer prefers the sound of stainless steel, it suggests that the harmonics produced by stainless steel pipes are different. Therefore, the fundamental frequencies of the organ pipes will stay the same, but the resulting harmonics will be altered.
ii. The fundamental frequencies will be higher while the harmonics will remain unchanged: This option is unlikely because stainless steel is generally denser and stiffer than tin/copper alloys. These characteristics would typically result in lower fundamental frequencies rather than higher ones. Therefore, this option can be ruled out.
iii. No change in fundamental or harmonic frequencies: This option is also unlikely. Since the customer specifically prefers the sound of stainless steel pipes, it implies that there is a difference in the sound produced by different pipe materials. So, it is reasonable to anticipate at least some change in the fundamental or harmonic frequencies.
In conclusion, based on the information provided, option i seems to be the most plausible. The fundamental frequencies of the organ pipes will remain unchanged, but the harmonics produced by stainless steel pipes are likely to be different, resulting in a different overall sound.