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The Arm/Cartridge Matching Myth

When I began my journey in high-end audio 36 years ago….no-one ever wrote about arm and cartridge matching nor tonearm resonant frequency…?
Over the last 10 years or so…this topic has become not only ubiquitous, but has mutated beyond its definition, to THE guiding principle of matching cartridge to tonearm….❓❗️😵
The Resonant Frequency can be calculated using a complex formula relating Tonearm Effective Mass to the cartridge’s Compliance….or it can be simply measured using a Test record of various frequency sweeps.
The RECOMMENDED Resonant Frequency of any tonearm/cartridge combination is between 8-12Hz.
But WHY is this the recommended frequency and WHAT does it really mean…?

The raison d’etre of this Resonant Frequency…is to avoid WARPED records inducing ‘resonance’ into the tonearm…..
Say what…❓😵
WARPED records….❓❗️
Yes…..ONLY warped records❗️😎
But doesn’t it have any meaning for NORMAL records…❓
None whatsoever…..😊👍
Let me explain….🎼

A badly warped record induces the tonearm to rise and fall rapidly on the ‘sprung’ cantilever of the cartridge.
Depending on the severity and frequency of this warping…..a subsonic frequency between 2-5Hz is induced so if your tonearm/cartridge Resonant Frequency dips into this frequency range….it will begin resonating and thus miss-track and/or induce hum through your system.🎤
Keeping the lower limits of your tonearm/cartridge Resonant Frequency to 8Hz simply insures against this possibility.🎶

So what about the 12Hz upper limit…❓
This simply insures against the possibility of any ultra low-level frequency information which MAY be on the record, also inducing this same miss-tracking or hum. For instance if your tonearm/cartridge Resonant Frequency was 18Hz and you had an organ record or one containing synthesised bass going down to 16Hz…..your tonearm may miss-track or you MAY develop a hum❓😢

So how many badly WARPED record do you possess…❓
I have three out of a thousand or so……and have NEVER experienced miss-tracking or hum even on these three…❗️😍

Yet these days….everyone (without exception it seems)…even tonearm and cartridge designers….happily follow the dictum of this Arm/Cartridge MATCH as if it affected sound quality…..❓
This Resonant Frequency has ZERO affect on the sound quality of a particular tonearm/cartridge combination and I have proved it hundreds of times with a dozen different arms and over 40 cartridges.

The best match for ANY cartridge ever made….is simply the very best tonearm you can afford…whatever its Effective Mass…😘
128x128halcro

Showing 9 responses by lewm

lewm
12,455 posts
 
Chakster, OF COURSE, there are extreme values for compliance and effective mass that might knock the Fr out of the generally accepted range of 8 to 12 Hz. My point is that the equation shows there is a lot of room for variation, and my other point is that we often don’t have correct data for our particular sample of cartridge or tonearm. These facts suggest room for experiments.
lewm
12,455 posts
 
But 99.9% of "suspended" turntables are fatally flawed in their design, on one way or another.  This is my opinion based on listening and looking. The ideas are good; the execution is questionable. Now, if you're talking about Minus K or Herzan platforms, that is another story. 
lewm
12,455 posts
 
Interesting.
Rules were made to be broken, especially in audio.
lewm
12,455 posts
 
The problem with your conclusion based on your observations is that you can have no idea what the actual compliance of your Shure cartridge is at this point in time. By now, it may be a low compliance cartridge which is actually a fairly good match for the FR 66S. I have very successfully mated an Acutex cartridge with my FR 64S, and the combination works beautifully, but the Acutex is 40 years old at this point and probably no longer exhibits its original super high compliance. So all I can say is it works, but I think that is weak evidence for throwing out the customs related to tonearm matching. On the other hand, I am all for trying things out in my own system before disavowing them.
lewm
12,455 posts
 
I would only place upper and lower limits on Halcro's proposition; it would not be a great idea to use a very high mass tonearm with a very high compliance cartridge, simply because of the resulting flexing of a very compliant cantilever which might cause physical damage, never mind resonance. Let say, an ADC XLM with an FR66S.
lewm
12,455 posts
 
I just want to be careful to point out that I am not even necessarily advocating breaking any rules (although I do it myself).  I am pointing out that what may SEEM to be in violation of the Fr rule (range of 8 to 12Hz) may not in fact be a violation, for one's own particular pairing of tonearm and cartridge.
lewm
12,455 posts
 
One of the reasons why there can be wide latitude for tonearm effective mass, if the target is a resonant frequency (Fr) of between 8 and 12Hz, is the very nature of the equation used to calculate Fr, which reflects the physical laws that govern Fr:  For example, I took the seemingly extreme examples offered up by Chakster a few posts up from this one, the idea of using a tonearm with 13g effective mass vs one of 30g effective mass, with a very low compliance cartridge like the Denon DL103, which he estimates to have a compliance of 8 at 10Hz.  If you assume about 10g for the mass of the cartridge and plug those data into the equation, the tonearm with 30g effective mass yields Fr = 9.06Hz.  For the tonearm with 13g effective mass, Fr = ~12Hz. Both of these results fall into the category of "acceptable".  Thus, to me it is no wonder that Halcro experiences no profound problems with apparent mismatching of cartridges to tonearms, especially since I think Halcro likes to use the Yamamoto Carbon Fiber headshell (as do I), which weighs only 10g.  If he's using a Yamamoto on his FR64S and FR66S, that would reduce the factory-stated effective mass of both of those tonearms by a considerable fraction, since the OEM FR headshells are very heavy.  If you couple these facts with the additional hypothesis that (1) individual cartridges, even brand new, probably vary in compliance from one sample to another by a fair amount, and (2) "vintage" cartridges probably have lost some springi-ness to their suspension, then nothing is really predictably verboten.  The vinylista is free to try anything.  I don't know why that makes anyone angry.
lewm
12,455 posts
 
Some calculate the effective mass of the tonearm/cartridge system backwards, starting with the compliance of the cartridge and the observed resonant frequency, using a test LP. But that depends upon the accuracy of the manufacturer of the cartridge in stating compliance. Also, Mark Kelly has developed a rather simple method to estimate effective mass; the problem is that I have forgotten it. However, search the archives on the Vinyl Asylum or try Vinyl Engine.
lewm
12,455 posts
 
My dear mother was an opera singer. When I was a medium size child, she had a very close friend who was a refugee from Nazi Germany and an opera singer as well, Wagnerian type, maybe a mezzo soprano. The two of them would often sing operatic duets whilst my mom played the piano in our living room. Our 50s vintage home had very large "thermopane" (double glass) bay windows. Believe me, those windows audibly rattled when the two of them got into it during a crescendo. I was always frightened that the windows would shatter at any moment. They probably did not shatter only because there were two panes with an air space in between them.

Harold, I don't think VTF has anything to do with tonearm effective mass. The effective mass does not change with changing VTF. I've got to side with Halcro on the FR66S; that is one high mass tonearm for sure.
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