Steven, >Thanks to all for the suggestions. In the end it was duplex noise. I've been following this thread, expecting it to be duplex noise. If the C7 is thirty years old I think it will be a C7B. If it hasn't been re-strung it will be due for it. But it likely will have a dead board in the first capo string section. Furthermore, the scale lengths at F21 are far too short in this piano (no 7 foot piano with a plain wire F21 can work), so it would benefit from a tenor bridge if and when it is rebuilt. The C7F was a major scaling improvement, with a 23 note bass which resulted in G#23, the first note on the long bridge, having a percentage of break at around 36% (the same as the 183cm F21 first long bridge note on the S&S model D). The note F21 on the C7B had a percentage of break in the low twenties. It was gutless on that note and refused to stay in tune if the weather dared change. Just turning on the air conditioning in the room was enough to completely stuff the tuning. All the C7 pianos before the C7F broke at E20/F21 and were a scaling mess, whereas the C7F is quite a respectable instrument compared to many other offerings in the 7 foot class. >Once muted everything was fine. Well sort of. The muting will tend to kill the duplex noise, but it will also be damping all energy which bleeds across the capo to the duplex segment. This will result in less sustain for those notes which have damped duplex segments. > I thought it was in relation to my filing and voicing but I now >realize that we had just moved this piano from a proffessors small >office to an auditorium. I believe the acoustics are what helped >pronounce the noise which was probably already present in the small >room but was not as audible? I will know for sure when we move it >back after the recital Sunday. Indeed. Its likely that the professor's room be will less lively at around 3.5K, relative to the auditorium, which will allow you to hear the duplex noise more easily in the auditorium. >It is interesting that the proffesor did not hear the noise until I >pointed it out to him while explaining the "funny" mute job in the >non speaking length of the strings. The prof's ears might have done a bit more work than yours, and he very likely has considerably more roll off. Older ears, in general, are less likely to hear duplex noise. Ron O. -- OVERS PIANOS - SYDNEY Grand Piano Manufacturers _______________________ Web http://overspianos.com.au mailto:ron at overspianos.com.au _______________________
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