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Galibier Turntables:
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Rega VTA Adjuster - $75
Application Notes
This adjuster fits the legacy implmentations - both RB-250's and RB-300's and not Rega's newer
designs (including, we believe the newere RB-250 and RB-300). Inquire if you have doubts.
If you have any doubts about your implementation, we suggest contacting us and going so far
as to drill a prototype out of scrap wood to test your measurements with your cartridge. We'd
hate to see you ruin a one-piece plinth/armboard by rushing this project. We can also discuss
reducing the thickness of your arm mounting area to gain VTA adjustment range.
Installation Notes
Study your Rega arm. You'll note that the arm stub is approximately 1.25" long.
The range of VTA adjustment available to you is the amount of left over thread after your
arm has been mounted. This is the post length minus all of the pieces which it passes through:
1) the VTA nut height addition = .080"
2) the thickness of your armboard (.500 to ???)
3) the bottom fixing nut = .250"
Assume the typical turntable with an armboard thickness of .750". These
numbers add up to 1.080" which means that the total +/- (peak to peak) VTA range available
to you is only .170" (1.250 - 1.080 = .170). Not very much room for error!
This is the reason that the Rega armboards we provide for our Galibier turntables are .440"
thick (armboards we provide for other pivoted arms are .875" thick).
An armboard thickness of .440 increases the available VTA adjustment range to .460" (peak to peak)
over that which would be available with a nominal .750" thick arm mounting area.
With careful planning, this will easily cover the broad range of cartridges we've measured. We've
observed the median height of most cartridges to be 16.9mm with a very small variance. This dimension
is the measured distance from the cartridge's mounting surface to the stylus. Should you later purchase
a cartridge which drastically varies from industry norms, you can use shims under the headshell or the
VTA nut to compensate for the height difference. If you're measuring your cartridge, be mindful of
keeping a steel ruler well clear of your cartridge. Failure to exercise caution could have catastrophic
effects on the life of your cantilever. Some cartridge magnets are very powerful!
Armboard Mounting Plane Height
There are numerous ways to think of arm mounting height. We'll reference this dimension as the drop
from platter surface to the plane at which the arm is mounted.
With our .440" thick armboards, the arm mounting surface should be 1.400"
below the platter surface.
As noted above, the thicker the arm mounting area, the less VTA adjustment range is available to you.
In order to maintain an equal upward/downward adjustment range as your armboard thickness increases
beyond .440", you'll need to raise the mounting plane by half of the thickness differential.
So ... if you have a .750" thick armboard, the mounting surface must be .155" higher
than the above example with a .500 thick arm board (.750 minus .440, divided by 2). This means that
the armboard should be raised so that it's now only 1.245" below the platter surface
(1.400 minus .155 = 1.245).
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Digital Scale
Turntable Shelf
Mint Protractor
Rega VTA Adaptor
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