Pianotech

Back to discussions
Expand all | Collapse all

String lengths?

  • 1.  String lengths?

    Registered Piano Technician
    Posted 10-14-2019 04:04
    Does anyone have a set of tenor-treble string lengths for any piano (Steinway M preferred)?

    Is there a resource for this?

    ------------------------------
    Blaine Hebert
    Duarte CA
    626-795-5170
    ------------------------------


  • 2.  RE: String lengths?

    Registered Piano Technician
    Posted 10-15-2019 00:50
    I tuned a  Kawai grand today and was able to get a set of string lengths for the Cs.  This was adequate for now.

    ------------------------------
    Blaine Hebert
    Duarte CA
    626-795-5170
    ------------------------------

    Original Message


  • 3.  RE: String lengths?

    Posted 10-16-2019 07:04

    1936 Stnwy M

    Speaking lengths in mm


    27 1009
    28 1001
    29 990
    30 979
    31 965
    32 948
    33 922
    34 900
    35 847
    36 798
    37 756
    38 715
    39 678
    40 640
    41 607
    42 572
    43 542
    44 511
    45 482
    46 456
    47 432
    48 412
    49 392
    50 374
    51 355
    52 340
    53 327
    54 312
    55 290
    56 274
    57 259
    58 245
    59 232
    60 219
    61 208
    62 196
    63 186
    64 176
    65 164
    66 156
    67 149
    68 142
    69 135
    70 129

    71 123
    72 114
    73 109
    74 102
    75 95
    76 90
    77 85
    78 80
    79 75
    80 71
    81 68
    82 64
    83 61
    84 58
    85 56
    86 54
    87 52
    88 50


    ------------------------------
    Philip Stewart, RPT
    NJ Piano Service
    609-774-7571
    www.njpianoservice.com
    njpianoservice@gmail.com
    ------------------------------

    Original Message


  • 4.  RE: String lengths?

    Posted 10-16-2019 07:20
    Good luck on C8 being 50 mm!

    ------------------------------
    Regards,

    Jon Page
    mailto:jonpage@pianocapecod.com
    http://www.pianocapecod.com
    ------------------------------

    Original Message


  • 5.  RE: String lengths?

    Posted 10-16-2019 07:37
    Scaling of instruments is an intrigue. The bottom note on an organ keyboard, C, represents a pipe of 8ft. So middle C, note 52 is 2ft and Treble C, note 64 is 1 ft. 

    Sound travels at about 1 ft per millisecond. I note from the string length quoted that the string for note 52 which is a shade above 1000 Hz is just over 1 ft.

    Is there an advantage to be had or audible aural difference when the string length is arranged to be that of the wavelength of the frequency in air?

    Best wishes

    David P



    --
    - - - - - - - - - - - - - - - - - - - - - - - -
    David Pinnegar, B.Sc., A.R.C.S.
    - - - - - - - - - - - - - - - - - - - - - - - -
    +44 1342 850594



    Original Message


  • 6.  RE: String lengths?

    Registered Piano Technician
    Posted 10-16-2019 13:55
    I only needed numbers to plug into an experimental spreadsheet.
    I am not redesigning a piano.

    ------------------------------
    Blaine Hebert
    Duarte CA
    626-795-5170
    ------------------------------

    Original Message


  • 7.  RE: String lengths?

    Registered Piano Technician
    Posted 10-16-2019 19:34
    My conversion shows 50 mm to be about 1.968498 in (approximately). This seems to be what I find most C 88s to be about or close to.

    2 inches is 50.8 mm.


    ------------------------------
    Blaine Hebert
    Duarte CA
    626-795-5170
    ------------------------------

    Original Message


  • 8.  RE: String lengths?

    Registered Piano Technician
    Posted 10-17-2019 01:49
    I've never been able to accurately measure much beyond a tenth of a millimeter. 

    The speaking length of C-88 in early pianos varies from around 47.5 to 51 mm. in later pianos it will be somewhat longer. There is no standard. Some of this variation is by intent, some by manufacturing variability. 

    ddf

    --
    Delwin D Fandrich
    Fandrich Piano Company, Inc.
    Piano Design and Manufacturing Consulting Services -- Worldwide
    6939 Foothill Ct SW -- Olympia, WA 98512 -- USA
    Phone 360.515.0119 -- Mobile 360.388.6525



    Original Message


  • 9.  RE: String lengths?

    Registered Piano Technician
    Posted 10-17-2019 02:01
    I have a 6" metal ruler that I put a bevel on the bottom edge (not quite sharp) to better access the capo bar contact area.  After the low tenor strut I don't bother with anything but eyeballing on the agrafffes, but then I  am not designing pianos.

    Long aluminum calipers are now cheap and readily available at Harbor Freight.

    ------------------------------
    Blaine Hebert
    Duarte CA
    626-795-5170
    ------------------------------

    Original Message


  • 10.  RE: String lengths?

    Registered Piano Technician
    Posted 10-17-2019 01:42
    What's the problem with 50mm at C88?

    ------------------------------
    David Love RPT
    www.davidlovepianos.com
    davidlovepianos@comcast.net
    415 407 8320
    ------------------------------

    Original Message


  • 11.  RE: String lengths?

    Registered Piano Technician
    Posted 10-17-2019 01:56
    Perhaps this begs the question: What is the perfect  string length (and diameter for that matter) for C 88?

    But then this gets into the question of what is the ideal string scale.

    The Kawai I just measured uses #14 on the top.  Steinway usually uses 13.​

    My philosophy is to see what the most successful (but not the most hyped) design is.  Steinway is considered great for a reason (plus some hype).  Yamaha has the time and money to do the research.  The Europeans have the experience.  I have them all as customers, but I aint the one choosing the pianos.

    Hmmm... I think I might just poll my teachers and musician customers.

    ------------------------------
    Blaine Hebert
    Duarte CA
    626-795-5170
    ------------------------------

    Original Message


  • 12.  RE: String lengths?

    Registered Piano Technician
    Posted 10-18-2019 03:01

    There is no perfect. Scale tensions vary depending on the designer's tonal idea. Average string tension (plain wire) ranges from somewhere around 145 lbs to probably 190 lbs, or thereabouts. The tension level influences timbre, power, impedance and affects both soundboard design and hammer choice. 

    The scale design, which includes both speaking length and string diameter, will be based on the tension targets of the designer. 

    Steinway pianos are relatively low tension pianos. The smaller pianos typically fall in the area of ~155 lbs). Concert Ds are much higher. The Steinway B has a rather non uniform scale design: as low as 123lbs in the low tenor climbing to around 165-170 lbs in the mid to high tenor and low treble before dropping back down to around 145-150lbs at C88

    Yamaha pianos (last I checked as they do change their scales periodically) are somewhat higher at around 175lbs. 

    Pianos like Bechstein, Boesendorfer and most concert pianos are higher still. 

    All other things being equal longer speaking lengths produce higher tensions as do thicker strings. However a specific tension target achieved by string length versus string diameter will yield a somewhat different tonal effect including inharmonicity. 

    Many of the early designers considered 160 lbs to be the ideal. Most pianos, however do not have uniform string tensions through the scale. Many drop off somewhat both in the very high treble and low tenor. Whether that's always by design or varied executions is unclear but both design and execution contributes to variability. Most manufacturers will not share their scale designs.  The most  uniform scale tensions are produced when speaking lengths in each section follow logarithmic progressions. 



    ------------------------------
    David Love RPT
    www.davidlovepianos.com
    davidlovepianos@comcast.net
    415 407 8320
    ------------------------------

    Original Message


  • 13.  RE: String lengths?

    Registered Piano Technician
    Posted 10-18-2019 07:59
    Kawai 14 = Steinway 13, I think, Blaine.

    Bob Anderson, RPT
    Tucson


    Original Message


  • 14.  RE: String lengths?

    Member
    Posted 10-18-2019 08:30
    Now I know why the scale designer also known as the scale was considered the most valuable asset in the factory. It is amazing that some excellent pianos where built without computers or the aid of fancy machines and so much was worked out using math and hand measurements but then again certain principles and rules of physics where discovered/learned/followed to make it all work. In the case of Chickering & Sons they had an in factory lab where they ran experiments. Jonas Chickering was self taught but fortunately his son Charles Frank worked with him and the skills where passed along.

    ------------------------------
    James Kelly
    Pawleys Island SC
    843-325-4357
    ------------------------------

    Original Message


  • 15.  RE: String lengths?

    Registered Piano Technician
    Posted 10-19-2019 21:37
    I measured C88 on a S&S style S at 64 mm after breaking it twice trying to tune it. Certainly NOT what the scale designer had in mind.

    ------------------------------
    Greg Graham, RPT
    Brodheadsville, PA
    ------------------------------

    Original Message


  • 16.  RE: String lengths?

    Registered Piano Technician
    Posted 10-19-2019 21:50
    I had the same experience. Out of frustration and bewilderment, I called New York. I was told some had escaped the factory with the wrong dimension. I tuned several notes in that section flat out of necessity. I guess nobody is completely free from mistakes.

    Paul McCloud
    San Diego

    "Once upon a time, I thought I was wrong. But I was mistaken.."


    Original Message


  • 17.  RE: String lengths?

    Registered Piano Technician
    Posted 10-20-2019 00:04
    Your's was not an isolated experience.

    ddf

    --
    Delwin D Fandrich
    Fandrich Piano Company, Inc.
    Piano Design and Manufacturing Consulting Services -- Worldwide
    6939 Foothill Ct SW -- Olympia, WA 98512 -- USA
    Phone 360.515.0119 -- Mobile 360.388.6525



    Original Message


  • 18.  RE: String lengths?

    Registered Piano Technician
    Posted 10-20-2019 01:39
    On 3 different Steinway D's, all within one year, I broke 3 C# 7's. I decided that there might be a weakness in the scale at that point, and I stopped trying to get stability with overly firm blows.

    ------------------------------
    Susan Kline
    Philomath, Oregon
    ------------------------------

    Original Message