<!doctype html public "-//W3C//DTD W3 HTML//EN"> <html><head><style type="text/css"></style><title>Re: Lighter or Heavier ?</title></head><body> <div>At 12:41 AM +0200 14/7/02, Stéphane Collin wrote:</div> <div><br></div> <blockquote type="cite" cite>After all, go to Steinway Hamburg, and try 10 model B's.  Not 2 will have the same sound.</blockquote> <div><br></div> <div>Thanks to their CC sound board construction, and that no two technicians will voice a piano the same.</div> <div><br></div> <blockquote type="cite" cite>Not 2 the same touch feel.  Though, they are made following the same (computer controlled) uppermost demanding specifications.</blockquote> <div><br></div> <div>I find myself having difficulty accepting this second sentence. If they were built to exactly the same specification they would 'feel' the same. I have rebuilt many Hamburg Steinways, and measured their hammer/key ratios. Therefore, I do not believe that they are built as accurately as you describe. Just measure a few Hamburg action hammer/key ratios to confirm this for yourself.</div> <div><br></div> <div>A part-image of an action, with an accompanying formula for calculating the hammer/key ratio can be found on our website at;</div> <div><br></div> <div>http://overspianos.com.au/anrt.html</div> <div><br></div> <div>I have followed some of this thread. The relationship between hammer/key ratio, hammer weight and required key leads is interesting regarding overall system inertia. Although the inertia effect of excessive key leads is well understood, a heavier hammer will have a similar effect to an excessive quantity of key lead. The practice of using many key weights to offset a poor combination of heavier hammers with a higher than appropriate hammer/key ratio, will make a poor situation worse.</div> <div><br></div> <div>Heavier hammers, just like adding more key leads, will result in extra action system inertia. Although the weight of a heavier hammer might seem moderate when compared to the use of an extra key lead, the effect of each extra gram of hammer weight must be multiplied by hammer/key ratio. A one gram heavier hammer will increase the down weight by 5.5 grams if the hammer/key ratio is 5.5:1. The inertia effect from hammer weight can be similar to that of adding key leads. To the pianist, the feeling of inertia will be the same, no matter what the cause.</div> <div><br></div> <div>Over the years, we have learned almost to predict the hammer/key ratio range of an action by the overall weight of the keyboard and action, when pulling it out of the piano for repair. There is a preponderance of high ratio/heavy hammered instruments out there, with disastrous quantities of lead, inserted in a vain attempt to make them playable.</div> <div><br></div> <div>Dale, I saw your post this morning when you wrote the following:</div> <div><br></div> <div>At 4:28 PM -0400 13/7/02, Erwinspiano@AOL.COM wrote:</div> <blockquote type="cite" cite><font face="Times New Roman" color="#0000FF"> I'm working with a 1920 Baldwin 5 ft. 8 inch grand that proves the point. Keys are full of lead in the bass with 4 leads still at note 40. Horribly heavy static touch weight ,70-80 grams</font></blockquote> <blockquote type="cite" cite><font face="Times New Roman" color="#0000FF">     I moved the capstans 3/8 of an inch to try to overcome the key leverage and match the only  choice of shank and wippen for this odd beast available and I still had to shoot for low hammer /strike weights. Note 4 needed no more than  8 grams ,note 16- 7.5 grams note 40-6.5 grms ,you get the idea.  Even at this I'll only be able to remove 1 or possibly 2 leads in the bass. (7-8 per key)<br>     The true fix would be new keys and leverages to match the parts available which wasn't an option in this case. I tried.</font></blockquote> <blockquote type="cite" cite><font face="Times New Roman" color="#0000FF">   It will work but I've never moved capstans that far. Wow!</font></blockquote> <div><br></div> <div>Some of the grand pianos from that era typically had hammer/key ratios as high as 8.0:1 with light hammers. I'd be very interested to know what the measured hammer/key ratio is for the Baldwin you describe. even after you moved the capstan 3/8". The fact that you still needed many key leads with such light hammers to achieve an acceptable down weight, would lead me to suspect that the ratio remains relatively high. If you still have the piano in your workshop, I'd be interested in the figures.</div> <div><br></div> <div>Regards,</div> <div>Ron O.</div> <x-sigsep><pre>-- </pre></x-sigsep> <div>_______________________<br> <br> OVERS PIANOS - SYDNEY<br> Grand Piano Manufacturers<br> <br> Web: http://overspianos.com.au<br> mailto:info@overspianos.com.au<br> _______________________</div> </body> </html>