Battery voicing as discussed by Andre Oorbeek (sp?) is needling in the area below 3:00/9:00 (around the staple) for the purpose of regaining power (thus the term "battery") that was lost due to excessive needling or from a hammer that lacks power in the first place. It doesn't always work. You don't use that tecnique to mitigate attack.
The main purpose of needling in the upper part of the hammer is to get the hammer to absorb more energy so that less is delivered to the string and balance the impedance characteristics of the soundboard with the energy delivered by the hammer.
To do that effectively picture the hammer as a too tightly coiled spring between the strike point and the molding. Your mission, should you decide to accept it, is to get the spring to open up. You will need to needle in the area from 9/3 on either side toward the crown to do that. The amount, depth and location will depend on where the hammer as s spring is too tight and how effective lower or higher shoulder needling is at getting the spring like quality of the hammer to open up. Some hammers will respond well some not so well. The less responsive the hammer is the more toward the crown you will need to needle and the more needling will be required. There are directional techniques (where the needles enter and point) for different parts of the hammer.
Usually Abel hammers will need to be worked closer to the strike point than others because they are not as responsive as some other hammers (another discussion) when it comes to opening up that tightly coiled spring. Generally speaking the needle direction is a radial pattern (think spokes of a wheel) with caution being exercised as you approach the strike point. Depth of penetration needs not be more than 8-10 mms anywhere (3/4" is way excessive unless you like breaking off needles) and often less in the upper area of the hammer or, of course, on smaller hammers such as you find in the treble
If you're in California on the 27th of November (4th Tuesday) come to the Santa Clara chapter meeting where I'm giving s 90 minute presentation on the subject (I just gave the same discussion to the SF chapter) or contact me privately if you need clarification. It's not rocket science or mysterious when you conceptualize it properly. It's just experience,feel and working methodically with defined purpose.
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David Love RPT
www.davidlovepianos.comdavidlovepianos@comcast.net415 407 8320
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Original Message:
Sent: 10-05-2018 11:23
From: Laura Wright
Subject: Voicing Abel Special Pressing hammers
Just a follow-up question: When it comes to deep needling, how deep is "deep"?
Thanks to all who have responded!
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Laura Wright, RPT
Ivory Keys Piano Service
Durango CO
Original Message:
Sent: 09-22-2018 07:53
From: Paul Williams
Subject: Voicing Abel Special Pressing hammers
Andre Ooorebek also discusses this in his book. Yes deep needling around the 3 and 9 O'Clock areas.
Original Message------
Battery voicing is deep needling in the low shoulders, the areas around 9:00 and 3:00 o'clock. This gives the hammer better potential for absorbing the shock at the top when the strike point hits the string; if the low shoulders have too much tension the tone will be harsh. Kawai's high-speed videos of a hammer striking the string really demonstrate the importance having a good foundation near the bottom-for a split second the top flattens and the upper shoulders bulge out, leaving the low shoulders to absorb the force. (Don Mannino sometimes shows these videos during his convention presentations, and they provide a lot of insight into hammer function.)
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Kent Burnside, RPT
Franklin TN
615.430.0653
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