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Ryan, if BDB's offering seems a bit too overwhelming, just list your measurements, the best you can and I will calculate the pattern for you using my Treble Strings Tension Handbook as I did with so many pianos in years past. Start with C8 and list like this:

88 (C8):2
87 (B7): 2 1/32
86 (A#7): 2 1/8
85 (A7): 2 1/4

etc. down to 27 (B2) (where your plain wire ends).

From notes 88-63, to the nearest 1/32" is sufficient. From notes 62-47, to the nearest 1/16" is sufficient. From notes 48-27 (27 is B2, the lowest plain wire on your piano), to the nearest 1/8" inch is sufficient.

If there are any unisons where one string is tied off, be sure to indicate this on your chart. Example:

65 (C#6) 6 1/32 Tied Off

******************************************************************

While I can see that if using a spreadsheet, you may want to have finer measurements and when converting to metric or English decimal, you would want to have 3 decimal places, as I've said from the beginning, the end result is always going to be a decision of one wire size to the other. The final result will look like just about any other piano, merely a difference sometimes of 2 or 4 more unisons of a particular wire size and conversely, less of another. If the piano you are working on really had size 14 all the way to C8, you can certainly expect that I or anyone else would come up with something like 4 unisons of 13 and 6 of 13 1/2 for the top 10 unisons.

In a few instances, you may see a particular wire size cross over the break from the treble to the tenor and in some rare cases, you may actually see the wire size decrease slightly across that break. It all depends upon the curvature of the bridge. Look at some small recent vintage Baldwin grands and you will see that.

To answer Jurgen's question about volume and inharmonicity: I agree with BDB that maintaining the smoothest possible curve of tension is the primary goal. When this is done, the inharmonicity curve inevitably follows suit. The volume factor does as well. Volume and inharmonicity go hand in hand with tension. If you have dips and peaks in tension, you will also have dips and peaks in inharmonicity and volume. Therefore, if you build the smoothest possible tension curve, you will have the best tuning stability, ease of predictable tuning, either aural or electronic and the least amount of voicing problems.

The volume issue does however start to be a problem in the low tenor when you get to the larger sizes of wire and are trying to maintain your tension curve. That is why I am suggesting and will most likely end up suggesting a few two string unisons in the very low tenor if Ryan posts his data.

I ran the inharmonicity numbers on one scale, and there was a slight increase near the break, but it was less than 0.02%. I may be interpreting the numbers wrong, but the important thing was that it was negligible.

Remember, none of these things were calculated when the pianos were designed.

Indeed. Many manufacturers just made some kind of curved bridge, others a kind of straight one and just laid on some wire with little more thought to it than that. When they ran out of room in short pianos, they just made the bridge take a left turn at the end and when they found that any wire heavier than size 19 sounded too loud, they just used lighter wire to the end of it. I've seen all too many pianos with size 18 wire all the way down to B2 on a 5'2" grand. Absolutely horrible sound and even worse tuning stability.

Fewer spools of wire meant a less costly inventory and less confusion for the stringer. Heavier wire sizes are harder to handle and were perhaps more expensive. Any rebuilder today can make a substantial improvement with no other alterations than carefully selected wire sizes.

As you can see from the spreadsheet, although the lowest strings of the sample piano are thick, most of the strings are thinner than usual. (There are 22 #13 notes!) This would have been much cheaper, because there is more length to the pound using thinner wire.

BillBremmerRPT, would you like for me to post the speaking lengths on here, PM you, or send you an email? I have them ready. Thanks.

Any way you feel comfortable, Ryan. If you post on the Forum, I will return my caluculations here and they will be open to scrutiny which I am not afraid of but others may have slightly different opinions, so it's up to you.

If you send them by private e-mail, you may use an attached file. Put the words "piano scale data" in the header. If you respond privately, I can still post an abbreviated summary such as "6 unisons of 13, 4 of 13 1/12, etc. My e-mail address is Billbrpt@aol.com.

If you want to enter them into my spreadsheet, I can go though my process. Send me a message when you are done, and I will give instructions.

Oh, and be sure to let us know which notes do not share a string with an adjacent note. Otherwise I will assume that they all do, in which case there needs to be an even number of notes with each wire gauge.

It's not a bad idea at all to let both me an BDB do it and you can choose whichever design you feel most comfortable with.

I am playing around wih a scaling spreadsheet these days. Unless it is some kind of a secret, I would be interested in seeing the raw data (speaking lengths and, if available, original wire gauges) and run the numbers through the sheet I have, in order to compare with other programs.

We could have a whole re-design committee for Ryan's piano!

But Ryan should also be wary of "design by committee" and choose the design he feels most comfortable with and not make a composite one or take all results and average them.

Alright, here it goes:

88 (C8): 2 1/8 2.125
87 (B7): 2 7/32 2.21875
86 (A#7): 2 5/16 2.3125
85 (A7): 2 13/32 2.40625
84 (G#7): 2 17/32 2.53125
83 (G8): 2 5/8 2.625
82 (F#7): 2 3/4 2.75
81 (F7): 2 29/32 2.90625
80 (E7): 3 1/16 3.0625
79 (D#7): 3 7/32 3.21875
78 (D7): 3 3/8 3.375
77 (C#7): 3 17/32 3.53125
76 (C6): 3 23/32 3.71875
75 (B6): 3 29/32 3.90625
74 (A#6): 4 1/8 4.125
73 (A6): 4 5/16 4.3125
72 (G#6): 4 17/32 4.53125
71 (G6): 4 25/32 4.78125
70 (F#6): 5 1/32 5.03125
69 (F6): 5 9/32 5.28125
68 (E6): 5 7/8 5.875
67 (D#6): 6 3/16 6.1875
66 (D7): 6 1/2 6.5
65 (C#6): 6 13/16 6.8125
64 (C5): 7 1/8 7.125
63 (B5): 7 7/16 7.4375
62 (A#5): 7 27/32 7.84375
61 (A5): 8 7/32 8.21875
60 (G#5): 8 21/32 8.65625
59 (G5): 9 1/8 9.125
58 (F#5): 9 21/32 9.65625
57 (F5): 10 3/16 10.1875
56 (E5): 10 7/8 10.875
55 (D#5): 11 1/32 11.53125
54 (D5): 12 1/4 12.25
53 (C#5): 13 13.0
52 (C4): 13 11/16 13.6875
51 (B4): 14 1/2 14.5
50 (A#4): 15 5/16 15.3125
49 (A4): 16 7/32 16.21875
48 (G#4): 17 9/16 17.5625
47 (G4): 18 5/16 18.3125
46 (F#4): 19 1/4 19.25
45 (F4): 20 1/8 20.125
44 (E4): 21 1/16 21.0625
43 (D#4): 22 1/8 22.125
42 (D4): 23 1/8 23.125
41 (C#4): 24 13/32 24.40625
40 (C3): 25 23/32 25.71875
39 (B3): 27 1/32 27.03125
38 (A#3): 28 7/16 28.4375
37 (A3): 29 7/8 29.875
36 (G#3): 31 5/16 31.3125
35 (G3): 32 3/4 32.75
34 (F#3): 34 3/16 34.1875
33 (F3): 35 9/32 35.28125
32 (E3): 36 1/8 36.125 (tied off)
31 (D#3): 36 29/32 36.90625
30 (D3): 37 1/4 37.25
29 (C#3): 37 3/8 37.375
28 (C2): 37 11/32 37.34375
27 (B2): 37 5/16 37.3125 (tied off)

I'm anxious to see the results you guys come up with. I'm very anxious to get started on the piano.

Roughly speaking:

1 - 21
2 - 20
2 - 19
1 - 18
2 - 17
4 - 16-1/2
4 - 16
2 - 15-1/2
16 - 15
4 - 14-1/2
10 - 14
4 - 13-1/2
6 - 13
4 - 12-1/2

Ryan,

This was indeed a very interesting project and puzzle to solve. I used the Piano Rebuilder’s Handbook of Treble String Tensions (and Other Characteristics) compiled by James H. Donelson RPT, published in 1977. It is a table of numbers that I used to rescale over 20 pianos back in the late 1980’s and early 1990’s.

What I gathered about the piano you are working with is that it has some unusually long speaking lengths in its hi-mid and low treble sections. Therefore, smaller than usual wire is recommended than for most pianos in these areas (as BDB pointed out in contradiction to what the Klepac chart suggests). Also, at the very top, the speaking lengths were slightly long and could have even used some #12 and #12 ½ wire but with the size #13 and #13 ½ wire that I suggested, the tensile strength lies still well below the maximum of 70% which is recommended. I have seen many scales with even higher tension in this area.

The “%tensile” figures indicate the percentage of tension at theoretical pitch before the string would break. Since most people will tune these highest strings considerably sharper than that, one would certainly not want to exceed the 70% limit. Although I did not look up what size #14 would have provided in the areas where I suggest #’s 13 & 13 ½, I can well imagine that the tension would have been dangerously high. These wire sizes will also produce a good, strong sound whereas #’s 12 & 12 ½ may sound a little on the weak side. It is normal for most scales to have slightly higher tension in the highest part of the high treble.

The Inharmonicity column indicates the amount of difference between the 1st and 2nd partials, (one octave higher than the fundamental). You will note that the 4 highest strings have 1st partial inharmonicity of over ¼ of a step. This is normal in this area of the piano but if size #14 wire had been used, the inharmonicity would have been all the more exaggerated.

From the notes 80 all the way down to 30, I was able to keep the average tension hovering around 150 pounds as BDB has suggested. This should provide you with a light sounding and easy to tune piano with relatively low inharmonicity compared to many others. Only at the lowest end does the inharmonicity start to climb again but just very slightly. Also, at the lowest end, any wire size above #19 would tend to sound very loud and brassy, this is the reason for dropping back to a bichord (2 string unison). You will notice in looking at the figures, in spite of increasing dramatically the size or wire, the pounds of tension and % tensile drop off precipitously but the inharmonicity rises slightly. This is entirely due to insufficient speaking length and why some kind of compromise is called for. If #19 wire were used in this area, the tension would drop very low indeed and tunings would be very unstable in this area, responding dramatically to the least rise and fall in relative humidity. The tone would also be weak and “wolfish” sounding.

Do not be alarmed by the words “estimate” you see beginning at note 62 and below. This certainly does not mean I merely estimated which wire size should be there. The very fine measurements you took from notes 62 and below sometimes fell in between the figures that are in the table I have. The author noted that these fine increments were passed over to keep the table of figures from being too cumbersome since such small increments make literally no difference in determining which wire size to use in this area.

However, if one uses a computer spreadsheet and calculations, having such small distinctions does make for an even smoother looking curve. Therefore, I estimated what those figures would be for you. The estimates are merely the very insignificantly small differences in tension, % tensile and inharmonicity. If I had used either the next fraction up or down, it would have made no difference whatsoever in the choice of wire size.

I noted that you identified C4 as C3 but I corrected that in the chart you offered. I placed asterisks (***) to help the figures I supplied line up better so you could more easily see the curves of all four characteristics: wire size, pounds tension, % tensile and inharmonicity.

You will notice that at note #68, I made the notation “back-up/break”. I assume this is the break between the high treble and the treble. In many pianos, the bridge goes straight across this break but I imagine that on your piano, the bridge continues to curve. Therefore, there is a noticeable “jump” in length between notes 68 & 67, which calls for a smaller wire size. So, the pattern of wire sizes takes a step back from 14 ½ to 14 which is unusual, virtually never seen in finer pianos. But in this case, it provides for the smoothest curve possible. I have done this a number of times before on smaller, lesser quality pianos. Trust me; it is an improvement, not a mistake in judgment.

Only down at notes 31 and below do I run into a dilemma. I imagine this is where the bridge takes a “left turn” and creates the “hockey stick” appearance. The speaking lengths increase very little for each successive note when they should increase a whole inch or so for plain wire to be effectively and best used this low in a scale. This is where specially designed wound strings would best be used but that would require adding hitch pins, replacing agraffes with 2-string types, etc. So, where you see the words, “bichord”, simply guide your plain wire through the outside holes in the agraffes and bridges and leave the centers blank. Put in a tuning pin in the center hole but just leave it blank. If in the end, you don’t like the outcome, you can always use size #19 to the bottom, possibly putting size #20 on the lowest, tied off unison.

It is unfortunate that you must buy some sizes of wire for only one or two unisons. Just buy the smallest quantity you can for those sizes. Also, you’ll note that I skipped size #18 wire entirely. This is just how it worked out. I also used size 19 ½ and 20 ½ wire when most pianos skip half sizes anywhere past size #18. Again, this was the best compromise. You certainly can choose to use size #19 from note 32 all the way down using 3 string unisons if you so choose. Many pianos are built this way and apparently so was this one. The compromise I offer is in my opinion a better solution, however.

Here is a summary of the scale design I came up with for you:

Scale design for 1928 Hobart M. Cable Grand

88-87: 13.0 (2 unisons)
86-79: 13.5 (8 unisons)
78-73: 14.0 (6 unisons)
72-69: 14.5 (4 unisons)
68-65: 14.0 (4 unisons) (note unusual reversal of pattern)
64-63: 14.5 (2 unisons)
62-59: 15.0 (4 unisons)
58-45: 15.5 (14 unisons)
44-41: 16.0 (4 unisons)
40-39: 16.5 (2 unisons)
38-35: 17.0 (4 unisons)
34-33: 17.5 (2 unisons)
32: 19.0 (1 tied-off unison) (Note that size #18 is skipped entirely)
31: 19.5 (1 bichord unison)
30: 20.5 (1 bichord unison)
29: 21.0 (1 bichord unison)
28: 21.0 (1 bichord unison)
27: 22.0 (1 bichord unison) (no need for tie-off, skip last hitch pin)

Here are the complete details:

Note//Speaking length//wire diameter//lbs tension//%tensile//Inharmonicity

88 (C8):***** 2 1/8 2.125//13.0//175.12//63.912//57.02
87 (B7): **2 7/32 2.21875//13.0//170.08//62.074//53.85
86 (A#7): **2 5/16 2.3125//13.5//175.39//60.481.//54.58
85 (A7): *2 13/32 2.40625//13.5//169.18//58.340//52.26
84 (G#7): 2 17/32 2.53125//13.5//166.79//57.515//47.91
83 (G8): *****2 5/8 2.625//13.5//159.81//55.106//46.49
82 (F#7): *****2 3/4 2.75//13.5//156.25//53.880//43.32
81 (F7): *2 29/32 2.90625//13.5//155.47//53.612//38.99
80 (E7): ***3 1/16 3.0625//13.5//153.81//53.037//35.49
79 (D#7): *3 7/32 3.21875//13.5//151.36//52.195//32.65
78 (D7): *****3 3/8 3.375//14.0//157.67//51.359//32.24
77 (C#7): 3 17/32 3.53125//14.0//153.78//50.090//30.20
76 (C6): *3 23/32 3.71875//14.0//151.93//49.490//27.56
75 (B6): *3 29/32 3.90625//14.0//149.35//48.649//25.41
74 (A#6): ****4 1/8 4.125//14.0//148.38//48.331//22.93
73 (A6): ***4 5/16 4.3125//14.0//144.48//47.062//21.55
72 (G#6): 4 17/32 4.53125//14.5//150.85//58.468//21.07
71 (G6): *4 25/32 4.78125//14.5//149.63//46.040//19.07
70 (F#6): *5 1/32 5.03125//14.5//147.61//45.481//17.46
69 (F6): **5 9/32 5.28125//14.5//144.90//44.584//16.14
68 (E6): *****5 7/8 5.875//14.0//150.49//49.019//11.15 back-up/break
67 (D#6): **6 3/16 6.1875//14.0//148.71//48.441//10.17
66 (D7): *******6 1/2 6.5//14.0//146.21//47.625//9.37
65 (C#6): *6 13/16 6.8125//14.0//143.08//46.607//8.72
64 (C5): *****7 1/8 7.125//14.5//148.01//45.543//8.68
63 (B5): ***7 7/16 7.4375//14.5//143.69//44.211//8.21
62 (A#5): 7 27/32 7.84375//15.0//151.00//44.000//7.75 (estimate)
61 (A5): **8 7/32 8.21875//15.0//147.00//43.000//7.00 (estimate)
60 (G#5): 8 21/32 8.65625//15.0//145.00//42.500//6.50 (estimate)
59 (G5): *****9 1/8 9.125//15.0//144.38//42.094//6.09
58 (F#5): 9 21/32 9.65625//15.5//152.00//42.400//5.78 (estimate)
57 (F5): **10 3/16 10.1875//15.5//151.12//41.861//5.23
56 (E5): ****10 7/8 10.875//15.5//153.41//42.497//4.52
55 (D#5): 11 1/32 11.53125//15.5//153.00//42.50004.00 (estimate)
54 (D5): *****12 1/4 12.25//15.5//154.50//42.798//3.54
53 (C#5): ********13 13.0//15.5//155.02//42.941//3.13
52 (C4): *13 11/16 13.6875//15.5//153.097//42.409//2.86
51 (B4): ******14 1/2 14.5//15.5//153.068//42.401//2.55
50 (A#4): *15 5/16 15.3125//15.5//152.079/42.127//2.30
49 (A4): *16 7/32 16.21875//15.5//152.00//42.000//2.05 (estimate)
48 (G#4): 17 9/16 17.5625//15.5//158.783/43.984//1.67
47 (G4): **18 5/16 18.3125//15.5//153.80//42.604//1.59
46 (F#4): ****19 1/4 19.25//15.5//151.41//41.941//1.46
45 (F4): ****20 1/8 20.125//15.5//147.43//40.840//1.37
44 (E4): **21 1/16 21.0625//16.0//143.50//39.800//1.29 (estimate)
43 (D#4): ***22 1/8 22.125//16.0//149.40/39.315//1.25
42 (D4): ****23 1/8 23.125//16.0//145.40/38.263//1.18
41 (C#4):24 13/32 24.40625//16.0//144.50/38.000//1.06 (estimate)
40 (C4): *25 23/32 25.71875//16.5//150.00//37.500//1.03 (estimate)
39 (B3): **27 1/32 27.03125//16.5//148.50//37.000//0.93 (estimate)
38 (A#3): **28 7/16 28.4375//17.0//146.00//36.500//0.86
37 (A3): *****29 7/8 29.875//17.0//151.316//36.114//0.84
36 (G#3): **31 5/16 31.3125//17.0//148.00//35.300//0.77 (estimate)
35 (G3): ******32 3/4 32.75//17.0//144.33//34.446//0.73
34 (F#3): **34 3/16 34.1875//17.5//147.00//33.200//0.72 (estimate)
33 (F3): ***35 9/32 35.28125//17.5//140.00//31.500//0.71 (estimate)
32 (E3):36 1/8 36.125 (tied off)//19.0//150.95//29.950//0.85
31 (D#3): *36 29/32 36.90625//19.5//147.00//33.150//0.91 bichord
30 (D3): *******37 1/4 37.25//20.5//145.78//30.435//1.08 bichord
29 (C#3): *****37 3/8 37.375//21.0//136.50//27.083//1.25 bichord
28 (C2): **37 11/32 37.34375//21.0//121.00//24.000//1.41 bichord
27 (B2):37 5/16 37.3125(tied off)//22.0//117.25//21.575//1.72 (estimate) bichord

I have this record on file and can send it to you as an attached, MS Word document if you wish by e-mailing me at Billbrpt@aol.com. I will post some first time stringing tips for you tomorrow.

My best regards and wishes for success in this project,

I started by looking at a scale around 140 lb., but saw that there would be a problem with the lowest plain string. So I went with a linear increase from 125 lb. up to about 150 lb. at the top. I was not willing to share a hitchpin between two different gauges of wire, and took an average when necessary. The result actually goes from about 108 lb. to about 160 lb.

So it is a little lower tension than Bill's, and it is not terribly different from other scales, except that the area where the gauges stay constant are higher than is traditional. There are not any sizes skipped, other than half sizes in the tenor, which is traditional. It uses the existing hitchpins as it was designed. So it is a reasonable scale, which will not throw someone else who works on it.

I noticed also that the area where there are many of the same size wire in a row was higher than usual too. This usually occurs in the #17 wire size area. I have done the sharing of two wire sizes on one hitch pin a few times. I found it was possible to put two strings together and create a single tie-off with them, for example. In one instance of an older Baldwin grand, I hid the splice between two strings beneath the string braid. I didn't find these kinds of tricks necessary in this case, however.

The conversion or the lowest tenor strings to wound bichords is commonly done these days. Sometimes, a rebuilder fills in the center tuning pin hole and finishes over it. The wire sizes need to be marked on the piano one way or the other such as a neatly written number on the plate by the tuning pins or on the bridge itself. I used to use number decals that I bought at an art store. I don't really see the minor alterations I suggested as being a problem for anyone. If a string should break and it needs to be replaced but the wire gages are plainly marked, there should be no question about what goes where. While plain wire bichords in the low tenor may surprise someone who has never seen such an alteration before, even a visually impaired person can easily detect which wire goes to a pin and that there are only two strings, not three.

Some scales do skip wire sizes but they are usually whole sizes past #18. In this case, some of the higher half sizes worked out better. I noted that BDB used only one #18 but also that the original also skipped that size.

-12 Unisons of sz. 17 1/2
-5 Unisons of sz. 17
-3 Unisons of sz. 19

I would not insist upon, just recommend the bichords and the sizes I suggested. For the lowest 3 notes, the original design of 3 #19 would not be very good. However, I would say that what BDB suggested:

Roughly speaking:

1 - 21
2 - 20
2 - 19

...would also be quite reasonable and could also use 3 string unisons without skipping any holes or hitch pins. But these 3 lowest notes would be quite loud and brassy sounding, so very aggressive hammer voicing would be called for, especially for the very lowest note. Another alternative could be to make only that lowest note a bichord, skipping the last hitch pin (but using #21 wire, not #22). These lowest strings would still have extremely low tension however and would have more trouble staying in tune but not as much and as extremely so as the original design, just in between what I suggested and the original.

I'll take back the comment I made about making a composite. I think substituting BDB's idea for the lowest 5 notes as I mentioned above is a perfectly reasonable idea. I just think it's important to consider all the benefits and consequences. While I don't see a problem with the conversions/alterations I suggest, BDB seems to think there is that possibility. So, in the end, Ryan the final decision will be up to you but whatever decision you make, there is always the possibility of changing it. None of what was proposed by either of us will lead to a point of no return.

One final comment I would have about the original design: the large number of 17 and 17.5 wires are in the usual area that they occur except that the sizes are curiously reversed (unless Ryan mistakenly listed them that way). This would in this case however, be very poor design indeed. The tension would go from extremely low to very high and then back to low again, so would the volume and so would the inharmonicity except in the lowest strings where it would remain about as high or higher than in my design. I don't know what any of the figures would be for note 27 (B2) with #19 wire because that is considered so unreasonable as to be off the chart! No calculated ETD program could deal with it very well at all.

I doubt Ryan measured the original wires correctly. It is not easy to do even if you are skilled with the use of a micrometer. Sometimes you have to look more for changes, than accurate measurement, and base it on your knowledge of past scaling practices. The numbers Ryan gave were so at odds with those practices that I never considered that they were accurate.

I have also considered that it is possible he has not measured the lengths as accurately as I might like. I am more certain that the scale design was not particularly good. If I were to consider changing hitchpins, I would probably use overwound strings on the lowest 5 notes. But this piano is probably not worth the effort.

I also suspect that the lowest notes will not be ideal. But I bet they would be better than they were originally. It is probable that the lowest strings were thinner than either Bill or I suggested, which would mean that they would have very low tension. (If the piano has agraffes, make sure the holes in them are big enough! You may need to ream them.) So whatever you do is likely to be an improvement.

I reingineered the strings of an old 1895 Sohmer Grand (original strings) using the Travis book. Took me all day but I think it was worth it. A few observations: Most of the original string gagues were beyond their flexibility for the note they were supposed to produce at that length given the necessary tension required, therefore the wrong strings (possibly due to A435 original calculations versus A440); My range ended up being much greater, starting with 11 at the top instead of 12, and 22 at the bottom instead of 20; I also added several half steps in string sizes that were not originally there; Note that when old strings stretch they are actually thinner in the middle of the string than toward the ends - so measuring near the far ends are closer to the original size; I found a cheap electronic tape measure online for about $14 that had decimal places for measuring; I think next time I will use the excel spreadsheet, but cross reference it against the Travis scale to make sure they are within flexibility range; The Travis book does not work on the bass strings so make sure you send the last string length and diameter to the base string company so they can make a smooth transition between the bass strings and the treble; Some pianos have a crooked bridge, I assume to make some compensation, but the tension must vary in an odd way, as I have seen several later Sohmer pianos (1930-1940) with cracks in the sound board near the crook.

Wire strength has improved over the years. Unless there is some real anomaly with the scale design, there should be no problem staying within the proportional limit of the strings. Besides, there is nothing that you can do about it, short of redesigning the bridge. It changes with the wire gauge: If you decrease the wire gauge, you decrease the tension and the proportional limit. The only place it would be a problem is with the bass strings, and that is up to the bass string designer.

I just ran some scenerio comparisons for the 1906 Crown upright originally engineered at A435 with the "Calculating Technician" spreadsheet by Dave Roberts (converted to excel by Douglas K. Rhodes, RPT).

They state that the three critical factors are, in priority, Volume; Breaking point; and Inharmonicity.

What I found was that in the string range #27 to 88, when the original string dimension range #18 down to #12 wire was tuned up from A435 to A440, that the volume decreased by almost 50% -- primarily in the #27 to #37 keys, as they transition to the bass section.

When I expanded the wire diameter range going from #22 down to #12 the pattern of volume replicated the original chart, but with the only difference being the pitch, as I converted to A440.

I tried to post the three charts on this BBS (original strings at A435, original strings at A440, and new broader string range at A440) but could not figure out how to do it.

If anyone is interested I can send it to you in a word document, just e-mail me.

Volume range on the first chart (original strings, A435) is from about 260 to 120.

Volume range on the second chart (original strings, A440) is from about 150 to 120.

Volume range on the third chart (expanding new strings from original #18-#13 up to #22-#12 at A440) is again from about 260 to 120 like the original chart.

Keeping the string range the same, the volume gap increased between the bass section as volume decreased -- the change narrowed the volume difference between the bass section and treble making it a smoother transition.

Tension, breaking point, and inharmonicity all remained within parameters on all three charts.

I did find someone who is winding the new bass strings in Canada in Iron instead of copper, like the original. He double-winds and says the bass will be "booming." He had to order the iron wire from England. The first ten strings are copper-wound. Starting at #18 in the treble section, together with a timid single-wound copper bass section may be appropriate, but I am taking painstaking measures on this piano, which is in some ways somewhere between an exact restoration, and a renovation to modern. "Same sound but modern key." I want Debussy to send shivers up your spine, and lift you up to the top of a spire of a cathedral!