One of the highlights of West-Pac was the class given by head Fazioli tech Claudio Valent, focusing on voicing. I thought it would be nice to document the Fazioli procedure here as a resource.
Perhaps the most striking feature of the Fazioli voicing process is its consistency and precision, achieved in part by drawing lines along the sides of all the hammers, to define areas of the shoulder. As a starting point, lines are drawn on the sides of hammers at the end of each section. First, a line is drawn down the center of the molding and extended to the tip of the crown. Then a line is drawn perpendicular to that line, extending out to shoulders on each side of the hammer, establishing "3 o'clock and 9 o'clock" positions. The placement of this line is 3 mm below the tip of the molding, or, where underfelt is present, 3 mm below the top of the underfelt. (If someone understands this differently, please horn in. That is what I gathered, and my question to try to clarify was brushed off). And finally, lines are drawn bisecting both the right angles, extending to the shoulders at a "1:30" and "10:30" position. (I am not sure what they do in the top couple octaves - seems like it would either be an extension of lines from lower in the piano, or a somewhat different scheme. But it didn't come up).
Using the ends of each of these lines as a reference, a straightedge is laid along the hammer shoulders, and lines are drawn at the center of the crown, and at each of the positions I mentioned: 9;00, 10:30, 1:30 and 3:00. An additional line is drawn on either side of the 12:00 center line, 3 mm from that line graduating down to 2 mm in the high treble.
All voicing is done using #5 needles. Initial pre-voicing is done using a 3 needle tool with 10 mm long needles, inserted fully in a pressing manner (not jabbed). Five strokes are inserted on either side of the hammer in the areas between 9:00 and 10:30, 1:30 and 3:00. Insertion is according to the Renner pattern, aiming at a spot midway between the molding and the felt surface, down toward the staple area of the hammer. IOW, the insertions are at varying angles, all aiming toward the same spot. And the insertion points are spaced as evenly as possible within the defined area.
Three subsequent needle insertions are done with different lengths of needles, in different, overlapping areas. First, 8 mm needles are inserted in the same area as the 10 mm needles (9:00 to 10:30) but at a different angle, this time entering the felt at a right angle to its surface (headed straight in). Something like 7 - 10 insertions each side, evenly spaced. The second insertion uses 6 mm needles, and begins overlapping what was just done, maybe from 10:00 up to 11:00, again inserted at a right angle to the surface. Finally, 4 mm needles are used, again overlapping the 6 mm needles a bit, and going up to the top line.
For the first two insertions (10 mm and 8 mm), a somewhat wider spaced voicing tool is used, wider than most standard tools, and the needle insertions are in line with one another. For the 6mm and 4 mm insertions, a narrower spaced tool (the most common spacing I think) is used, with insertions staggered from side to side, forming a diagonal grid.
Following needle insertions, the hammers are filed through four grits, 120, 240, 400, 800 (I think). Leveling and mating as usual. Then listen and refine voicing with further needling as needed. Watching him on the screen, it looked like he went all the way up to the middle of the crown in some cases, angling out a bit. And then some shallow chopstick work on the crown itself.
Playing the piano to listen, he played three volume levels, more or less FFF, mf and PP. The louder were for deeper needling, the PP for chopstick.
Alignment of hammers and una corda position is somewhat unusual: the corner of each hammer is chamfered (filed), and the una corda position set so that on a soft blow the corner does not make the third string sound, but on a hard blow it does.
More could be added, and perhaps someone else who was there will care to chime in.
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Fred Sturm
University of New Mexico
fssturm@unm.edu "The true sign of intelligence is not knowledge, but imagination." - Einstein
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