I mentioned in passing the other day the question of that section of the string between the hitchpin and the brass duplex bridge and suggested it was significant without having anything particular in mind. I now have a case, which I find interesting. I posted an illustration also of the two upright agraffes that serve as the bridges of the monochord I was using. In a later message I had set up a trichord in a similar fashion... \\----xxxxxxxx----[\]___________[/]-----------O`------------------------// From left to right, the strings pass from the wrestpin over a soft bearing to the first upright agraffe. Between this and the second agraffe we have the 60 mm speaking length. The wires then pass over the movable duplex bridge to the hitchpins, which are parallel to the bridges. The distance from /] to O is also 60 mm and the distance from O to // is 120 mm. The trichord is tuned to top A. I strike the note somewhere to the right of [\] (or anywhere) and obtain a good clean ringing sound with good sustain. I now hold my thumb between [/] and O to mute the back length of back duplex. The sound now produced is very similar and hardly distinguishable from the first. I now mute the string to both sides of O so that only the speaking length can sound. Again, there is barely any detectable difference. Now for the interesting bit. I mute only the section running up to the hitchpin //, ie the section that has twice the length of the speaking length. The effect is calamitous. Striking the string now produces the sort of tone you would get from a thick mug or flower-pot with no ring or sustain either in the speaking length or in the duplex length. If I move O to a different position, the note is revived and the muting of the right hand length does not have the above effect. This is a very rough and ready experiment and I not interested in any small differences in tone due to the 'duplex' length but only in the severe deadening effect of muting the 120 mm length. The arrangement would be unlikely to occur in a real piano, but there may be other combinations that would have a similar effect. Any ideas? JD
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