@JohnBAngel and others. We had pets growing up but I do not remember any having discomfort when she played. I remember my grandfather tuned the piano on alternate weeks and the lower keys had a quite visceral quality, more felt than actually heard. Each key had several strings (I think 3 each), which needed to be slightly out of phase with each other but not enough to beat.
Are you sure the lower keys had multiple strings?
I grew up playing piano. From about age 12 onward I was playing a Yamaha baby grand. While the majority of the keys had three strings, the number of strings decreased to two and then one in the low register. The lowest strings are much thicker.
I didn't remember the exact cutoff points, but found a description:
"The grand piano has about 230 strings for the 88 keys. Generally, the ten lowest pitches have one wirewound string. The next 18 pitches have two, and the last 60 have three strings each."
Irv, JohnBAngel -So I think I have this all straight - it makes sense that longer strings have more overtones/harmonics, but take longer to vibrate. String mass, material and tension contribute, also.
Just read an article in Wikipedia (I know, don't believe everything) that explains the importance of size of instrument body in proportion to the length of strings for optimal timbre (be heard over an orchestra).
Basically, it looks like "violin" is good, "viola" strings would need to be 1.5 times the length of violin strings to be optimal, "Cello" is good and the "Dbl Bass" would need to be twice it's size to have optimal sound in proportion to it's strings.
I'm assuming this is the reason for Hutchin's Octet?
The article I gave the link for explains the reason the "Imperial Grand Piano" was made - for Bach's "organ works for piano". Ravel, Debussy and Bártok all composed pieces for this piano. Also (I just wanted to point out), "The extra nine keys not only give additional notes but they enrich the sound of the piano in all registers, generating a deeper and more satisfying sound." - according to the article in the link.
Can't wait to see what you come up with, Irv!
The lowest note on the imperial grand was Co, which resonated at 16 hertz (this is all coming from a YouTube video). Manual tuning was performed by touching the midpoint of the string while striking the key with the other, to evoke the audible C1.
Success is the progressive realisation of a worthy ideal. —Earl Nightingale.