LP eccentricity, spindle hole center,The fix??????


Hi all,

I'm one of those audiophiles, 67 years of age, that wonders about the effect of the accuracy of the center hole. Some of the LPs I put on the TT have play due to a center hole that's punched out of round, too large or what ever.

I'm playing a record on a Denon 308 direct drive table using a system devised by a LJT Mfg in Canada to reduce eccentricity and help flatten warped records using a peripheral ring clamp in conjunction with a 1420 gram spindle clamp. The trio comes along with a cnc machined polycarbonate centering disc that straddles the record after the clamp ring is set registering on the outside diameter of the record. I can feel play regarding the center hole as I implement the OD centering device. I'll measure it tomorrow, just a few thousandths. The music sounds fine to my ears but I wonder what the relationship is to the record grooves, the outside diameter, and the center hole.

A while back a TT was made that had an extra arm that MEASURED THE ECCENTRICITY of the record and re centered the disc for play, it sells for big bucks if you can find one.

FINALLY, Your thoughts on the question?

regards, Ken Fritz
kftool

Showing 3 responses by kftool

Dertonarm,

The center spindle was not omitted. The spindle dia. on the
Denon is .284 inches; the smallest diameter generally found on LPs. If i find a record with a larger hole I notice the back and forth motion of the arm. I then put the polycarbonate centering device back on the clamp ring and diddle it back and forth which re locates the LP on the smaller spindle. Putting the arm back on tells me if it's centered properly, or at least as best as my eye can tell. I believe most, if not all tables have a spindle dia of .284 inches, at least my two Sota tables have that same dia.

Ken
Has2be,

Whenever you think you're the craziest person on the planet, someone trumps you.

Thanks for the reply, Ken
Hi Raul,

It's been a while since we crossed threads. I have a feeling that by now you have a few more tone arms and cartridges; Ain't it great! I'll send 50 bucks to kick it off if I can get a Happy meal coupon with my tax free donation.

regards, and" Enjoy the music." A friend once said that to me.

ken