The problem is that when the pedal is raised, so all the dampers are on the strings, the single-string basses resonate equally if I play a chord in the middle octave. When I release the chord, the single-string basses can be heard resonating for a few seconds, making a racket. It is them because by blocking them with my hands, the resonance stops. But shouldn't they not resonate since the dampers are in perfect contact? They are new dampers, I don't know if that helps, and they have 3 tufts! Thanksssss. Alessandro
You haven't told us if it is an upright or a grand. In any case, if the felt is new, it is "simply" a matter of regulating them. On an upright piano, the bass dampers are quite troublesome because they easily lose their "centering" relative to the strings every time the action is removed. Try looking inside and see if each damper is well positioned or if it has shifted laterally. If that is the case, you just need to reposition them on the strings (they are flexible). Otherwise, you need to call a technician to regulate them. Another hypothesis: check the regulation of the sustain pedal.
The regulation of the dampers is a "tedious" job that must be done with precision. Resonance can be caused by various misalignments. One must also check the release of each one individually and of the pedal (all dampers together). I assume it is an upright. It is the regulation that gives me more and more to do, but, as Francesco says, a minimal inaccuracy can cause a significant sound problem.
I am responding after a long time and I apologize for it. Thank you all so much. Yes, it is an upright piano; apart from the 3-string keys which dampen very well, the single-string ones do not and make a racket. I will follow your advice by trying to understand if it depends on a misalignment or a lack of adhesion. The latter doesn't seem likely to me, but perhaps it is minimal and I need to run some tests. Thanks again, I was losing hope. I understand that a technician would be ideal, but I cannot afford one at the moment. I will keep you updated in case the problem is resolved. See you soon.
in these cases it is advisable to change the bass felts, which MUST be aligned during gluing onto the instrument. It is not advisable to move the alignments too much... even a slight inaccuracy is enough to create resonance even in the treble. (the harmonics go into resonance)
P.S. The felts must be of the original width (generally 9mm or 8mm). Moving the old dampers now with the intention of centering the deformed felts could create a distance problem between them (generally it is minimal and they could get stuck during the lift. Watch out!)
