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Tail Piece Adjustments.... continued.( to maximize string power and focus.)
...Now let us discuss how we might adjust the tailpiece frequency to the ideal 198 HZ. tap tone frequency.
...The goal is to make the tap tones for the waist of the bass bar at each string position match the back plate and bridge tap tone of 198 HZ
...Before we begin this stage, it is best to already have evened out the fingerboard tap tones so they are the same along the length under each string and that the nut matches the fingerboard at each string position too ( all at 176 HZ, same at top plate).
...Now if we a fitting a new tailpiece, the first thing we want to do is select one that is close to our goal tap frequency ( 198 HZ).
...For example, say that the tap tone of the tailpiece waist behind the E string is 'low' compared to our goal frequency of 198 HZ:
  In this case, the tap tone for the E string can be raised by sanding or scraping the section of the tailpiece behind the E string as shown on the photo below in dark red color:
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...Scrape or sand this dark red area evenly to raise the tap-tone of the E string on the tailpiece until it reaches 198 HZ.
..If tap tone is too high, scrape along the blue guide line until it reaches 198 HZ.
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...Adjust the tail piece for each string position until they all sound in unision and at 198 HZ.
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. Tap along the line for each string as shown at left, listening for any high toned areas.
...If you find a higher toned area, then either turn the tailpiece over and scrape directly under the too high area until it is even or just scrape the top surface of the tailpiece until even in tap tone all along the imaginary line for each string down the length of the tailpiece.
...When the tap tones all along each string line (as shown in red) are even in tone, then go on to the next step.
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Step One:
Step Two:
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...Tap down across the 'waist area' on the tailpiece, directly behind the string in question and compare this tap tone to the back plate (at 198 HZ) or to the wood tap reference tool you might have already made.
...Now we want to adjust until this is 198 HZ uniformally across this 'waist' area. When accomplished, our instrument will produce its maximum power.
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Step Three: If the tailpiece tap tone is too low:
Step Four: If the tailpiece tap tone is too high for a particular string:
...Now let us say that the tailpiece tap tone at the waist behind the string in question is higher sounding than 198 HZ:
...In order to lower the tailpiece tap tone for that specific string, scrape the area of the top of the tailpiece that corresponds with that string to lower the tap tone of the tailpiece for that string to unison with the fingerboard tap. Scrape the area shown in dark red until the tap (blue arrow) is at 198 HZ.
...When adjusting the tailpiece while still on an instrument, you must protect the varnish from possible damage. What I tend to use is several layers of manila folder paper slid under the tailpiece and taped in postion. If our scraper slips, we just contact the protective layer and the varnish is protected.
...Remove a small amount of wood from the top surface of the tailpiece at a time and continually check the tap tone unitl 198 HZ is reached for each string position.
(c) 2017 by David Langsather
..To review: to raise the tap tone of one string on the tail piece: scrape wood from the top surface of the tailpiece directly behind that string position and behind the waist (toward the end pin)
...Below is shown the area to scrape to raise the 'D' string connection to the tailpiece: {Blue arrow shows where to tap the tailpiece.}
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...Another way to lower one side of the tailpiece tap tones is to scrape wood from the area shown below to lower the tap tones of the strings on that same side of the tailpiece
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Lowers the tap tone of both the 'A' and 'E' string position on the string bar.
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..Wood scraped from the side surface here, which lowers the tap tone of the strings on that side of the tail piece....
Note: Please refer to the article on "rub tone" technique to pick out a tailpiece with 'rub tones' matching the rest of the instrument. (including on the string bar of the tailpiece.) See idex topic selection on home page.
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To adjust (lower) the tap tone for D string of the tailpiece.
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...Another way to raise the tap tones of one side of the tailpiece is to scrape wood from the out side edge of the tailpiece as shown below to raise the tap tones of the strings on that same side of the tailpiece:
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Raises the tap tone of both the 'G' and 'D' string position on the tail piece at waist area.
..Wood scraped from the side here, raises the tap tone of the strings on that side of the tail piece at the waist behind those strings....
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(revised 8/2017)
Page AA_33
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...The string bar of the tailpiece (in the photo white in color) is tuned separately and to a frequency of 242 HZ. This will sound in harmony with the tailpiece proper but two steps up on the Wood Tone scale: 176 HZ, 198, 213, 242, 289 HZ... This ensures quick instrument response.