---------------------- multipart/alternative attachment The terms high and low tension scales are most inappropriate. High where, low where? >. . Brinsmead is worth a lot of examination and applied a great deal >of attention to his string scales as well as to every other aspect >of his pianos, which are among the very best. Well this is indeed a surprise. Are you just taking John Brinsmead's word for the quality of their instruments, or it is something that you have noticed. >The 6'9" Kirkman of 1860 has as near as possible equal tension (ca. >155 lbs) from A85 down to the end of the long bridge. Have you actually measured the scale of the 6'9" Kirkman right down to the break, and entered the data into a spreadsheet - graphing the results? If you haven't, send the scale lengths and diameters to me and I'll convert the resultant scale graphs into jpegs so the whole list can see it. >Most of the other pianos I've looked at have been German and here I >detect two "long bridge schools", those (eg. Bechstein, Steinway) >who have the bridge follow a parabola (as though to achieve equal >tension) and those (eg. Bl=FCthner) who by putting a bulge in the >bridge before the tenor to give your "high to obscenely high" >tensions in this region. Do you mean by "long bridge schools" that they have too many notes on the long bridge? None of the makers you mention have ever designed scales lengths on the long bridge with a uniform percentage of breaking strain on the long bridge (I presume you are discussing pianos in the 6'0' to 7'0" sizes here). While they may have more or less followed a log style trend down from C88 to somewhere around G35, they mostly compromise lengths adjacent to the plate struts (just to make the bridge easier to make - without a care for tuning stability. From G35 down the tension is progressively reduced until the lowest note on the long bridge is reached. Basically, they have fallen for the common trap of placing the break in the wrong place for the given length of the piano (read Ron N's post on this a couple of days ago). I suspect that too often folks are putting forward scaling theories which have been based upon incomplete measurement of scales. It seems that good scaling is being attributed to certain pianos which don't measure up on the spreadsheet. >As to the tailing off of tension at the other end of the long >bridge, this, to some degree, is almost universal on both grands and >uprights Since poor scale design is similarly almost universal. >I admit I have never found a scale that I'd want to imitate in a new >piano and I wouldn't expect to Keep looking John, if you look far enough one day it will happen. >. . even though much bass string design in the past was left to the >string-maker, who in England would be given a weight to work to -- >if a maker's set weighed seven pounds and the price of copper went >up, the astute owner would tell the string-maker to knock half a >pound off the weight of his sets so that he could maintain his >margin! What an appalling situation. So the the astute owner tells the string maker to compromise the product to build it to a price. Is this why the UK is such a force in piano manufacture at this time? > The string-maker at the same time would be working blind At is appears, so too is the manufacturer >Any scale of mine is likely to end up with a total of about 18 tons. What about the contemporary idea of looking for certain goals in percentage of breaking strain, impedance and inharmonicity. All being considered together, to arrive at a design which will have whatever tension it requires to achieve the desired afforementioned characterisitics? Ron O -- ______________________________ Website: http://www.overspianos.com.au Email: mailto:ron@overspianos.com.au ______________________________ ---------------------- multipart/alternative attachment An HTML attachment was scrubbed... URL: https://www.moypiano.com/ptg/pianotech.php/attachments/9e/27/c4/4b/attachment.htm ---------------------- multipart/alternative attachment--
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