The recent discussion about varying breaking strength in wire and its effect on inharmonicity, have given me a lot to chew on. Solicitation, L-modes, quadratic effect; its quite a bit to sort out. What fun!

I dug through the archive for everything I could find on wire, which was not much. I found two items from American Steel and Wire: Nerves of Steel from ~1936, and a Catalog from the Spring of 1914. I assume everyone has seen Nerves of Steel, but I will include it below anyway. It was the catalog that would prove interesting.

I have included everything in the catalog that had to do with piano wire. The interesting bit is in plate 4 under "Better Methods and Better Pianos" It gives a rather surprising reason why Chickering, as confirmed in Nerves of Steel, went to Worcester to have wire drawn to their factory specifications. I'm sure I've read this before, but the recent subjects discussed have brought its importance to mind. Correct me if I am wrong, but Chickering was concerned with sollicitation, if I am using the word properly

https://picasaweb.google.com/105412259108667869462/AmericanSteelNervesOfSteel

https://picasaweb.google.com/105412259108667869462/AmericanSteelWireCatalogExerpt1914#

Oh, yes. For those outside the US, I hope you can overlook the rampant nationalism of the 1914 piece. There was this time when America had this big ego...

HI thank you for providing those links. That could explain why those instruments have a so full tone, absolutely differnt from many ones. (very limited experience with Chickerings but the few I have seen had a very special tone)

I also work on very fine German pianos made by the Langlau factory.

The verticals have a low iH pattern, and a lot of tension (my guess).
That makes for a very nice tone, very long and singing. (with an interesting equilibrium between basses and high treble.

I will try to take on hour to measure the scale and verify what happens to the BS level.

Very interesting reading , there is a page which is not very clear, but the processes are very well described.

At those times I suppose that more mineral was used. no recycling...

did you send twice the same link by mistake ?

Regards

Oops, my brain was shutting down. All fixed.

All this makes me wonder what the phrase " high tension scale" means. could it referr to the high breaking strain percent rather than simply a high wire tension?

I have never found a definitive description of what is meant by "high" or "low" tension scale. Different speakers seem to use it differently. I personally don't use it and prefer to think about break point.

There are only good scales and bad scales. Good scales sound good, while bad scales sound bad. Better scales sound better with a minimum of voicing, while worse scales sound worse no matter how much voicing you do.

We use 75 Kg as a medium optimal tension, then high tension could be more and low tension less.

I will try to be sure of that.

Indeed more tension = less iH, but it may relate to the bS as well.

Just tested that again today by measuring iH before raising pitch, (435 to 442) the difference at A49 is not "so" large, but let's say from 0.69 cps to 0.60 , something noticeable anyway, with less nasal and barrel sounding tone, audibly.


Thank you Craig. By chance could you scan again the page which is not falt enough, it seem difficult to read (or may be I could download the original scan with a better definition ?)

The pics at the end, showing the different crystallization state of the wire depending of the number of passes, carbon content and other circumstances, are very interesting .

Possibly at those times the wire drown in England and in Germany had a too high carbon content.

I've been looking but I can't find the actuall catalog. I made those scans several years ago when I was trying to digitize the whole collection. I guess I was concentrating on quantity rather than quality.

My main interest was to post the text which demonstrates that by as early as ~1864 a strategic control of breaking strength was seen as a fundamental requirement of good scaling, even if inharmonicity was as yet undreamed of. It also demonstrates that the manufacurers were not always at the mercy of the wire maker. Of course, this was just at the end of the American Civil War. The Chickering firm was huge and could have bought the wire mill outright. This command of industry is not the historical norm.

I'll keep looking for the real catalog.

As a related side question; Is it known if Steinway drew its own wire or not? It seems to me that if you owned your own wire mill, then you would be free to adjust BS to suit your needs, throughout the scale, without anyone else being the wiser.

Here is my copy, all are welcome to download it.

Ameican Steel and Wire

It is about a 26 meg file.

Thank you!

Thanks for finding it.


(This is almost off-topic, and there may be a link already posted in another thread, but one of the books that the company published or supported is also available online--Piano Tone Building, proceedings from meetings in 1916-1918. Appears to also include their discussion of wood and piano building:

pdf: http://ia600807.us.archive.org/9/items/pianotonebuildin12pian/pianotonebuildin12pian.pdf )

Thanks for the document, highly appreciated.

I heard yet that wire manufaturers made wire that was to resistive .

Some era near 1900. (after major Int exposure of 1900) If you look at the data availeable you see the wire resistance grown to a level it was stronger than the actual wire, at some point.

Something about a too high carbon content for the musical tone to be really pleasding, possibly asking then for extra long strings scales.

It have been made more ressembling to actual standards shortly later, hence the interest of the AWS catalog article with that in mind.

At the same time most if not all French pianos where using locally drawn wire FIrminy which was at the same time softer and very stress resistive.

It is difficult to know if some manufacturers asked for special wire quality, but the archives of the Pleyel, Erard and Gaveau factories are at last partly availeable.

Some wire was treated against corrosion (as sopme recent Rposlau wire probably. I have in the shop a "tropically treated" piano : 32 years near the ocean and I have find very little corrosion and no rust.

The conference proceedings ("Piano Tone Building," see link above) turn out to be more relevant than I assumed. Starting around page 18-19, F.E. Morton, an acoustic engineer with the American Steel and Wire Company, argues for specific tensions and gauges and gives his formula for an ideal scaling.

Per the previous discussion: On page 20, he argues that the breaking point should not be considered, for it leads to putting too heavy a gauge on the bass strings, putting so much tension on the soundboard that its ability to respond to other octaves is reduced. He argues that the elastic limit is instead the most important factor.

I don't get the point, as you state it, as they are related, with different curves depending of the jauge

Elasticity raise until elastic limit, where there is a grey zone , then plasticity then breaking

Elastic limit and break point graph with parallel lines.

I was unsure, it may depend of the level of hardness obtained with the gauge , is not it (I thought of "relatively parallel")