To get back to the original complaint of "plate ringing" in the Baldwin piano, I presume the issue is with the SD10. The re-design of the Baldwin piano was to achieve more accurate downbearing, (the acu just hitchpin), and more sustain and resonance,partially achieved by exact termination of the speaking length, (the termination bars mounted under the Capo bar). The portion of string from the termination bar to the tuning pin was left "open" (not muted with felt). Don Mannino was on the right track with his suggestion that the "ringing" was coming from the open string section. Unfortunately, on the early models, there were some errant harmonics emitting from the strings in front of the termination. These could sound like they were coming from anyplace in the piano, but could be silenced by muting the offending string with felt on that open portion between the termination bar and the tuning pin. I found, most often, that the harmonics were coming from the first one or two strings after the treble break. They could be found by playing the note and muting the front portion with your finger til the offending note was found, then muted with felt. No need to mute the whole section, which would then defeat the purpose of the design. This problem was later corrected by a minor change in the design of the termination bars. In one of the posted comments, a person said that the hitch pins were mounted in the plate at 90 degrees. Not true. They were mounted with one degree of lean to the rear so that when the piano wire was at pitch, the tension would bring them to 90 degrees. Respectfully submitted, P McCutcheon, former technician to the design engineer of the SD and SF10 pianos at Baldwin.
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