Talk:Piano acoustics

message: I am suggesting we merge Railsback curve into this article, since currently it does not explain much that is not already described in more detail at Railsback curve. Eventually other acoustic properties of the piano might be added as well. - Rainwarrior 23:20, 9 June 2006 (UTC)
replies: text: It is definitely specific to the piano, but the effect does apply to a few other inharmonic instruments; not so much the harp as it has less tension and less sustain, and not at all the pipe organ (pipes are not appreciably inharmonic). - Rainwarrior 17:55, 11 June 2006 (UTC)
thread_title:  Merge from [[Railsback curve]] 

message: In the statement about longer is better (less inharmonic), the key supposition is indeed for strings at the same frequency. Another question. I know that most modern eletronic pianos work with samples from real pianos in several frequency ranges. That seems to imply they have to be tuned with a Railsback curve as well. Does anyone know this for sure? And how about synthesized keyboards? Are they inharmonic on purpose? How can an acoustic piano play together with an electronic one? −Woodstone 18:13, 28 June 2006 (UTC)
replies: text: I moved your comment down here, it was hard to spot wedged in there at the top. Is your first sentence a question? (Yes, it is important that the two strings being compared for inharmonicity are at the same pitch. Is that your question?) Sampling keyboards differ, actually. Some do take the railsback curve into effect, some do not, but most good ones do (I've played a few cheap ones that have had rather terrible results in their piano samples). Synthesizers do not in general, and should not, unless they are inharmonic in a similar method to the piano (FM synthesis, for instance, is often inharmonic, but does not have the same effect on tuning because it is a different kind of inharmonic). Acoustic pianos playing with electronic instruments, or any instruments really is kind of a dodgy thing. Often the ensembles are big enough that the problem isn't noticeable, or sometimes the problem actually adds a charming kind of character to the performance. Some electronic keyboards are retunable and will let you enter a custom Railsback type curve in case you're playing with a piano, but in my experience very few people who own these expensive keyboards actually learn how to use this feature. - Rainwarrior 23:03, 28 June 2006 (UTC)

text: It's really tricky to give exact numbers... different types of strings, different lengths of strings, different pianos have different amounts of inharmonicity. The Railback Curve doesn't have a specific magnitude, just a general shape that will be slightly different depending on the particular piano. - Rainwarrior 05:04, 30 June 2006 (UTC)
replies: text: http://www.goptools.com/gallery.htm Here you can see how some piano technicians look at piano scales, from Tremaine Parsons' PScale program, it looks the same as Sanderson's chart and the old Scale Designer program for Atari. I think they're all single iteration, but it balances with using one value for tensile strength. Mireut 21:23, 11 July 2006 (UTC)
thread_title:  Comments by Woodstone 

message: I have made major rewrites to much of the article.  I am a physicist, not a musician.  Most of what I know about pianos I learned from Gabe Weinreich when I was a graduate student at U Michigan.  He is one of the authors of the five lectures on pianos, and my addition of the section on multiple strings is based on my memory of his lecture.  The section on fundamental frequencies is basic physics, and perhaps could be replaced with a link to the article on vibrating strings.  The section on inharmonicity is physics-based, but I might not be doing a good job explaining my intuition.
I think that the merger with the Railsbuck curve is not smooth.  Right now, it duplicates much of what is said in the rest of the article.
I would not have voted to merge the articles.  The tuning system is only a small part of the acoustics of the piano, and the Railsback curve more appropriately belongs in the section on stretched tuning since it applies to all stretched systems.  Basically any instrument in which there are multiple sound-producing elements, from the harmonica to the organ to the accordian to the guitar also suffer from stretched tuning, and they all have their own Railsback curves for the same fundamental physical reasons as the piano does: the idealization of an organ pipe as a thin tube of air breaks down because of its finite thickness.
David s graff 22:27, 7 February 2007 (UTC)
replies: text: I noticed that Opus reverted my changes of piano acoustics.  I didn't really feel like my additions were off topic, but I later found pages on vibrating strings that were somewhat similar to mine.  I started my rewrite because there seemed to be a few basic mistakes in what you wrote.
First of all, you confused "Thickness" with "Linear Mass Density".  My nylon string guitar has thicker strings than my steel string guitar even though they are under much less tension because nylon is much lighter than steel.  This effect also explains why gold-wrapped strings would sound better than aluminum wrapped strings.
Also, your discussion completely disregards another key variable in determining string tone, tension.  A piano builder could always use strings of the same length and thickness but with different tensions.  Your section only discusses two of the four variables which determine string frequency.
Since there are four variables which can adjust tension, it can get confusing for the reader.  I could have changed the title from "String Length and Thickness" to "String Length, Thickness, composition, and tension", but that seemed lame, so I changed it to "Fundamental Frequency"
I felt especially in discussions of inharmonicity that the reader would need to be familiar with the effects of tension and the difference between thickness and mass density.  And since the physics is so basic (Basically, distance = rate x time) I thought it good to put in.  I might say that we don't need the equation for wave velocity, but then we should still say that waves travel slower on more massive strings and faster on tenser strings.
This may all come from our different backgrounds, Opus is a musician and to me his comments include just barely enough physics to get by.  I am a physicist, most of what I know about this really comes from the study of periodic stars (which actually obey basically the same equations as a trumpet, but can take days or years to oscillate) and I guess my comments include just barely encluded enough music to get by.  Could you instead try to work in some of my ideas? David s graff 22:57, 7 February 2007 (UTC)
thread_title:  Major physics input 

message: This article lacks precision of logic, terminology, wording, physics, music theory, and mathematics.  The inharmonicity equation ought to appear, carefully explained, in the article on inharmonicity, and used in this article to demonstrate the pitch phenomena to which piano tuning must comply.  The physics of string stiffness ought to be elucidated in one article or the other (or a third devoted to it), and the characteristic acoustics of struck strings ought, at least, to be mentioned, and linked to an article on the acoustics of stringed instruments -- plucked, bowed, and struck. D021317c 11:41, 4 October 2007 (UTC)
replies: text: Go ahead and make the improvements you propose. −Woodstone 12:54, 4 October 2007 (UTC)
thread_title:  Disappointing article 

message: *"That is obvious to every physicist. Would you demand a citation for "1+1=2"?"
The above comment was hidden in the article in response to a request for a citation. 1+1=2 is not comparable in that it should be obvious to everyone, not just mathematicians. Wikipedia policy, however, requires that once a citation is requested it is required. Hyacinth (talk) 01:32, 6 October 2010 (UTC)
replies: text: OK, that was my hidden comment. For a scientific question like this, I would request a proof, not a citation. What is citation in humanities, that is proof in science. Anyway, I found a citation and added it inline. --Peter Buch (talk) 12:15, 27 October 2010 (UTC)
thread_title: Citation request

message: My main complaint is that piano acoustics is a vast field. "Scientific American" included a nice article about it in the 1950s. Rossing and Fletcher contributed a nice book, as did Harry F. Olson. But this article so far only discussed a rather trivial subject, and does so in a way that hasn't anything to do with pianos, except perhaps for the layout of the keyboard. To get into the acoustics of the piano, you have to begin with the acoustics of strings, and then differentiate the acoustics of struck strings from bowed or plucked strings, and then introduce some concepts of differential equations, then the various effects of the soundboard, which are really complicated, and then you might be ready to examine the differences between theory and real-world measurements. Tuning is a rather minor aspect of the subject, and what makes it difficult is not even addressed here; not that it should be. It should have a separate article. So should the influence of inharmonicity on piano tuning. So should varieties of tunings and their names. So should practical aspects of piano tuning. So should the history of piano making and technology. So should industries allied to piano manufacturing. So should biographies of famous contributors to piano history. So should the impact of World War I on the strength of piano wire. So should fallacies in the field of piano acousics (which are quite numerous), so should the selection of materials for pianomaking. But almost all of the information already here belongs in a separate article altogether. It's practically unrelated to pianos, or acoustics. It's more about playing around with a calculator. Funfree (talk) 19:39, 26 May 2014 (UTC)
thread_title: Main complaint

message: Albert E. Sanderson, in one of his earlier patents related to the Sanderson Accu-tuner, presented an equation right at the outset. This equation, which I studied for years, is unparalleled for giving the ideal frequencies of each of the partial tones for each of the 88 notes (and potentially more) on a piano. Unfortunately, I had to send off for a copy of the patent from the patent office to read it. But other people may succeed where I failed, about fifteen years ago. There really ought to be a Wikipedia article on Sanderson, for many reasons, and another on the equation and its analysis. You can't understand the Railsback curve without it. (By the way, there seem to be a couple of Wikipedians following me around and pestering me like gnats. Please ignore them.) Funfree (talk) 15:28, 1 June 2014 (UTC)
thread_title: The best equation

message: In every source I have ever seen, all three of the above terms are specifically stated to mean *exactly and completely* the same thing, except with regard to whether the fundamental note qualifies as one of them. I think it would take a lot of *very* fine newer sources to dislodge that from my brain. Is it possible that there's a terminology mistake in this article so that something that isn't a partial has accidentally been called a partial? TooManyFingers (talk) 02:52, 24 August 2021 (UTC)
replies: text: Harmonics are by definition multiples of a fundamental (first harmonic is the fundamental itself). Overtones and partials are other frequencies than the fundamental produced by an instrument. On strings and wind instruments most overtones are close to harmonics, since they produce sound in a close to one-dimensional medium. On percussion instruments, like bells and  timpani, the sound producer is two-dimensional and overtones are much more complex. −Woodstone (talk) 05:37, 24 August 2021 (UTC)
thread_title:  Harmonics, overtones, partials