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arm mass/ cartridge compliance mismatch

Can someone explain the relationship of mass required to compliance or other relevant factors- both from the engineering point of view and with regard to sound?

MC manufacturers specify a range of arm masses that are compatible with a particular cartridge. What is the result of using an arm which exceeds the mass recommendations of the manufacturer? For example, if the arm mass is specified as ideally between 6-10g range, and one uses 12-14g mass arm what will the resulting effects be?
eguth
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seandtaylor99
1,262 posts
 
http://www.theanalogdept.com/cartridge___arm_matching.htm
eguth OP
10 posts
 
Many thanks for your informative help. And I shall look into the Allsop Orbitrac- it sounds very interesting.

Can you hazard a guess whether a van den Hul FROG (recommended arm mass 6-10g- compliance 35u) would work in an Audio Kuzma STOGI arm (modified by removing the finger lift)? The STOGI is specified as having an effective mass of 13.5g, but that is with the finger lift- so call it 13G.

Eguth
gregm
3,395 posts
 
That figure of 35 x10-6/dyne is too high. It may be STATIC compliance (at 0Hz) rather than dynamic (measured usually at 100Hz). Dynamic compliance is usually b/ween 10-40% of static.

Whatever the case may be, VdHul's recommend'n for a 6-10gr arms seems to indicate average compliance AND that yr proposed set-up consisting of Stogi+Frog is MOST likely to resonate outside the acceptable range.

ANYWAY, the formula to calculate resonant frequency (RF)is,
RF= 1000/2pi x sqrt (total mass x cu).
Cheers
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