I would be hesitant to use the ball pean technique in Kent's situation - maybe very lightly. A couple reasons:
First, it would tend to negate any una corda work that had been done (assuming it had been done)
Second, in the middle of fall semester is not a good time to experiment on the prime concert instrument in a busy hall. One wants to act with a lot of caution, "evolving" the instrument bit by bit.
Perhaps more to the point, while I wouldn't say never, I would tend not to use this kind of technique on lacquered hammers. That has to do with my own philosophy and procedures around the use of lacquer. I like to use the minimum material possible to get the desired effect, and to use the minimum manipulation of the hammers following application. My mental image is that I have felt that is not so dense, with a lot of space (relatively, compared to hard pressed) between individual fibers. What I am doing is stiffening those fibers enough to give the needed brilliance of attack, and power for forceful playing. This stiffness substitutes for the additional density in hard press.
Inserting needles into such a lacquered felt has a more focused effect than on hard pressed, because of the extra air space. The needles break down the lacquer structure in the fibers right around the needle, but don't have much effect farther out. With hard pressed, fibers are pushing on fibers more, so the effect is broadcast to a wider area. As I see it (and in the way I operate - with very controlled, focused insertion of needles) a lacquered hammer should be voiced by creating a kind of honeycomb structure, with stiff fibers that haven't been affected by needles, and more pliant ones that haven't. Done with finesse, you end up with a tone that "sparkles" without being brittle and harsh. But it is the fact that there is this mix of stiffness that creates this effect.
Hammering is at odds with my image: it would tend to break down the lacquer induced stiffness everywhere the hammer hit, creating a single degree of "lack of stiffness" down to some degree of depth. There would still be stiffness below for power, but the attack sound would probably lose the "sparkle" I am after (and that I graduate using tiny needles).
Admittedly, this is a theoretical objection: I haven't tried it on lacquered hammers. And I guess I am simply happy with the results I get with lacquer, so reluctant to try another technique that is at odds with my mental model, lacking experimental instruments I am dissatisfied with (all my practice room grands have hard pressed hammers at this point).
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A 2 oz ball pean hammer can be used to work and massage the surface without damaging the fibers or diminishing power. Support the tails and work over the strike area of the hammer with the pean end. This can sometimes have a great or even miraculous effect on juiced or hot pressed hammers that are particularly hard at the surface." -------------------------------------------
Fred Sturm
University of New Mexico
fssturm@unm.edu "The true sign of intelligence is not knowledge, but imagination." - Einstein
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