Fidelity Research FR-64 vs. FR-54

dc, Raul owns or owned a DP75; there’s not much he hasn’t played with at one time or another. I own a DP80 which I’ve mounted in a slate plinth with a Triplanar tonearm. So far as I have been able to determine, DP75 = DP80. This is a wonderful combination that I never use, unfortunately, because my other four turntables take precedence. It’s ridiculously good, compared to what else you can buy for similar market value. When it was in regular use, I did prefer it to a Technics SP10 Mk2, also in a slate plinth that was nearly identical to the one housing the DP80, in terms of dimensions and mass (65 lbs).

After my last post, I started thinking more about the "lack of damping" of the FR64S/66S. It occurs to me that the pivot bearing does incorporate some sort of damping action; the lubricant captured in its bearing gets viscous after prolonged periods of disuse, which suggests to me that even when warm it has a damping action. Also, we seem to be assuming that the stainless steel arm tube is completely empty save for the wiring. I don’t know that it doesn’t incorporate any sort of "stuffing" that might also contribute to damping. These two points, if valid, would take some of the air out of Raul’s and J Carr’s criticisms. This is not to say that their dislike of the tonearm is not also valid. I only suggest that we are making an assumption about cause and effect. We don’t know that the objectionable qualities those two report are necessarily due to "lack of damping". We and they only assume that connection.

Also, we seem to be assuming that the stainless steel arm tube is completely empty save for the wiring. I don’t know that it doesn’t incorporate any sort of "stuffing" that might also contribute to damping.

Hi Lewm,
Here is an article by Thomas Schick on rewiring a FR64 (not sure whether it was the FR64S)
http://thomas-schick.com/en/blog/fr-64
The second photo shows there was some black material clinging onto the internal wire harness, but I can’t tell whether it was just a piece of tape, or something like a shrink wrap. Either way, I don’t think it can be called damping, at least not for the armtube.

Lewm, Micheal Percy Audio sells some damping material called "EAR TAD Damping Foils" that 3M makes that is supposed to be the "cat's meow" for under damped tonearms, according to the dudes over at DIYAudio.  It's relatively cheap, but the trick is figuring out how much is enough.  You apparently don't want to wrap your whole arm with this stuff, but a little bit at the worst nodal spots is said to eliminate any ringing.  I'd guess halfway down the arm would be a good place to start, but I've never tried it.  I wonder if any other audiogon fans have ?

I'm not a customer for anything to damp my FR64S, as I have no reason to believe it's a problem in my system.  (See any or all of my earlier posts here.) I am using a Dynavector headshell on my FR64S and an Acutex LPM320 cartridge, which is a light weight MI type.  This tonearm/cartridge combo is arguably the most neutral of three other tonearm/cartridge combinations currently set up to work on 4 different turntables, in my two audio systems.  If I was having a problem with resonant colorations, I would simply get rid of the FR64S, instead of putting a bandaid on it. (Actually, I would first try the FR64S with a very low compliance MC, which is theoretically a better match than the FR64S with Acutex.)  The problem I certainly expected to have was to do with the mismatch of cartridge compliance (the Acutex cu = 42!) and tonearm effective mass.

Thekong, I have seen those photos by Thomas Schick.  I was thinking about them when I composed my last post, trying to recall whether his photos revealed any stuffing in the FR64S.  It's hard to know whether he removed some inert material before making his photos, so to clarify the situation with the wiring.  One could ask him, I guess.