It is a pity not to be able to know the mass of the arm to correctly interface the cartridge; are you able to know this?
@best-groove Since it was top of the line SONY tonearm along with PUA-9, you can look at the Sony cartridges specs for compliance. The arm was optimal for them, but it is also flexible, because there is an optional subweight to mount lightweight or even superheavy cartridges.
But again, since the
XL-88 and
XL-88D cartridges made for use with this arm, i want to remind that dynamic compliance of XL-88 and 88D is 20cu @ 100Hz, we have to convert it to 10Hz for correct measurements, the compliance will be 34cu ! This is relatively high compliance and for SONY PUA-7 it is fine. For lower compliance and heavier cartridges we can add sony subweight. We can also use different (heavy) headshell. I think the arm is perfect for wide range of cartridges from low to mid-high compliance.
The arm is so precisely made and it's a pure pleasure to use compared to many arms i've tried.
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More about Sony PUA-7
here:
The tone arm was born from the experience of PS-X9 development under the thought of resonance free.
Long span vertical bearings, precision radial bearings, etc. reduce fulcrum of fulcrum while maintaining high sensitivity.
Unnecessary resonance is reduced by the shell plug of the chucking mechanism.
Parallel wiring of litz wire reduces transmission failure due to inter-line capacitance fluctuation.
The high rigidity aluminum alloy pipe is adopted, and the bending rigidity 8 times that of the conventional one is obtained.
The inside four scan cellar by a special cam is carried.
A carbon clad shell SH-165 is included.
The output code comes with a litz wire using output plug with a gold-plated plug.
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Universal tone arm SONY PUA-7 specs:
Effective length: 235 mm
Overhang: 14 mm
Full length: 330 mm
Height adjustment range: ± 3 mm
Needle pressure adjustment range: 0 to 2.5 g
Cartridge weight range used (including shell weight):
*11.0 g to 19.5 g
*19.0 g to 27.5 g (when using sub weight)
Attached shell weight: 10.5 g (SH-165)