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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…😘
halcro
rodman99999
6,206 posts
 
@Zavato- You said that, even though you don't need one now; you still want a Disctracker. The one on eBay is still available.
halcro's avatar
halcro OP
2,664 posts
 
Hi Ralph,
Henry, Its more than being about warped records, if you read inbetween the lines of Kirkus's post above- if the effective mass is incorrect, you can actually have the stylus jump out of the groove of a perfectly flat, concentric LP.

An excellent example is a Grado on a Graham 2.2- does the well-known 'Grado dance' shortly before exiting stage left (IOW, jumps out of the groove).

The other issue is you won't be able to get the cartridge to track complex material correctly. So its a big deal and not just about warp.
I'm sorry I didn't get that from Kirkus' Post....❓👀
Apart from the possibility of Structure-Borne Feedback exciting the exact arm/cartridge Resonant Frequency.....the only other ways I know of, are by warped or off-centre records..❓👀
If you have other science-based evidence...or if Kirkus could support your claims...I'd be interested...😲❓
In any case...over hundreds of combinations of arm/cartridge interactions....I've never experienced what you claim....😃
Fairly good odds in my book...😍
halcro's avatar
halcro OP
2,664 posts
 
Thanks Al,
I knew that you would be able to explain this so that even a dummy (me) would get it....😬❓
And I got it.....😜❗️

Regards
Henry
halcro's avatar
halcro OP
2,664 posts
 
I would just like to emphasise Kirkus' point about 'calculated' Resonant Frequency...and 'measured' Resonant Frequency because they are rarely (if ever) the same...⁉️😫
Many arm manufacturers provide a dubious figure for their arm's Effective Mass whilst a large number provide no figures whatsoever....😷
The cartridge manufacturers simply provide a 'design target' for their compliance figures which can vary significantly from unit to unit....and also possibly changes over time...❓😱
The Fidelity Research FR-66s tonearm is renowned as one of the highest mass arms at 38 Gm Effective Mass...😲
I have measured the Resonant Frequency with a dozen high-compliance MM cartridges using the Shure V15 Type 5 Audio Obstacle Course test disc and have not recorded a figure lower than 8Hz or higher than 13Hz...👍
So either the Test Record is wrong❓.....or the recommended range is easily achieved in 'practice' as opposed to in 'theory'....❓👀
knownothing
1,690 posts
 
Just taking a shot in the (very) dark here, but isn't it likely that in practice it is the amplitude of the resulting resonances in the tone arm/cartridge/room/speaker system that are at least as critical as the resonant frequency itself? Such that the frequency range for various cartridge/arm combinations does not vary by that much, but the intensity of the response at the primary and harmonic frequencies can vary by a lot between various arm/cartridge combinations? The result being that theoretical and measured resonant frequencies look roughly the same for many combinations and nearly all within the "accepted" range. But in practice these resonant frequencies are actually excited by and interact with record grooves, room construction and sound fields from speakers such that the AMPLITUDE of the resonances of different cartridge and arm combinations in different listening environments can vary over a wide range, sometimes becoming problematic.

I don't even know enough about physics to get into real trouble, but the above is my very dumb way to try to summarize some elements of the discussion so far so that I can understand it. And it demonstrates to me why a better designed tone arm is highly desirable and can command a higher price, and perhaps why Halcro sees the whole problem as a myth. This coming from a bottom feeder who has only owned 7 turntables in five decades of listening, all cheap, used and/or free, and probably fewer cartidges over my listening life than Halcro has in his current collection, but I have run into this problem in a serious way at least twice.

kn
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