Screw-down reflex clamps vs. record weights


Recently we have seen more and more 'record weights' on the market. These are normally lightweight(300-400gr)and simply sit on the record. They do not appear to give priority to bonding the record to the platter.
Two outstanding record weights of this type are the Kuzma Ebony Record Weight and the HiFi Tuning VRO ('vinyl resonance optimiser') - there is a review of this(for those who read German) at www.fairaudio.de.
It appears that these clamps, rather than channelling disc resonances away through the spindle and main bearing and/or optimising contact between the record and the platter surface, seek to absorb them directly (i.e. into the clamp itself).
The Kuzma Ebony is a particularly interesting case since it has been introduced by a company that supplies screw-down reflex clamps as standard on its high-end turntables.
My question is: has anybody had any experience of these clamps - probably 'vinyl resonance tuners' is a more appropriate term - on their turntables as replacements for screw-down reflex clamps? Clearly as a way of dealing with warped or dished records they will not be of much use, but it may be that they do a better job of damping the disc.
I would be particularly interested to hear of experiences involving SME turntables (whose platters incidentally are covered with a bonded layer of 'Isodamp' damping material).
Thanks,
Peter
pgtaylor

Showing 5 responses by whart

I have been experimenting with the Stillpoints LP1 on my Kuzma XL, which is normally supplied with a heavy screw-down clamp. It definitely changes the sound in the following ways: the overall loudness of the system is lower; there is less apparent 'propulsiveness,' particularly in the upper bass; the midrange does seem more 'pacific.' I retuned my system to accomodate these changes, largely by fiddling with the crossover point and gain of the woofer on my Avantgardes, and adjusting the overall level of the system (i.e., I play it at a higher setting on the line stage). I spoke with Franc re using it in place of the factory clamp and he did recommend his ebony weight. So, in essence, there is no reason, according to the turntable manufacturer, why I have to use a screw down clamp.
I'm liking what the Stillpoint is doing. But I also changed out line stages recently, and that's made a dramatic increase in bass articulation. So, I readjusted everything again. And it sounds terrific. Right now, I'm sticking with the Stillpoints, but that isn't an across the board endorsement for you to go out and buy one.
Al- I have one like that from the 80's as well. I think, believe it or not, it was branded as a "Monster" product, but I'd have to look.
FrankC- when you said you compared it to the Kuzma XL, were you referring to the turntable? And the factory clamp for that table?
The XL mat is some kind of rubberized textile that is bonded to the top of
the platter. As far as what's best, screw-down clamp or weight, I don't
know- certainly, as I indicated above, Kuzma himself doesn't insist on a
screw down clamp for his own product (although sells the ebony weight as
an alternative).
FWIW, the Stillpoints has these little moveable plates on the bottom , facing
the record label, with some sort of resonance absorbing properties, which
are its raison d'etre.
There is a definite sonic difference between the Stillpoints and the factory
clamp- if I had to choose straight up, without adjusting the system as
described in an earlier post, I would probably choose the factory screw
down clamp. If I compensate for the sonic differences as I have by
changing the x-over and woofer gain, as well as overall system gain, and
note the exact settings for repeatability, that would probably be a fairer
'test.'
My Kuzma XL and factory clamp does use a spindle washer but I am not using it with the Stillpoints weight. I am continuing to experiment, but lost power most of last week due to the hurricane. We are now back up and running.