longitudinal mode?

[Andrew and Rebeca Anderson]

All strings of the unison excited the same short buzz about an octave 
+.  Had me chasing around a while for something but I couldn't 
isolate a sympathetic resonance.  I didn't think of lifting because 
all three were making the sound.  I could try it.  I did lift and 
level these strings last year.  The piano is on full climate-control 
with a cover most of the time and there has been very little 
variation in pitch.  I noticed it today with the lid off.  It was 
right next to the snares but the sound sure seemed to come from 
within the piano.  I'll have to check again when the orchestra 
instruments are distributed back to their classrooms/owners.

Andrew Anderson

At 03:36 PM 9/30/2007, you wrote:

>>Tuned a D this afternoon to prep for this afternoon's concert.  A#6 
>>had a short buzz a harmonic above the note.  I could not find an 
>>offending duplex (front/back) to mute.  Would this be a 
>>longitudinal mode?  Got any ideas to chase this one down?
>>Andrew Anderson
>
>Hi Andrew,
>I'd think not. The longitudinal would be way up there in pitch, and 
>I'm not sure they're even audible that high in the scale. Did you 
>isolate unison strings to see if only one made the noise? I'd try 
>repositioning the strings a tad, and lifting and leveling that unison.
>Ron N