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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
pryso
1,939 posts
 
Zavato,

"a small piston device that attached to the headshell and made contact with the LP- who made that?"

I remember those and believe they were sold by Discwasher.

Now everyone can sleep tonight. ;^)
almarg's avatar
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almarg
9,670 posts
 
10-13-14: In_shore
*******🎓*******
+1.

Notwithstanding the very minor quibble that I believe the reference to "1/3 octave" should have said "a little less than 2/3 octave," I'll nominate Kirkus' post for best of the month, perhaps even best of the year.

Thanks, Kirk. Good to see you posting again.

Best,
-- Al
bifwynne
2,206 posts
 
Ditto ... Kirk.

I own a "hot-rodded" VPI Classic. If you read some of my earlier posts from a few years ago, I had a devil of a time matching a cartridge to the VPI JMW uni-pivot arm. Many of the troublesome carties had compliance factors in the 20s.

And no surprise, the effective mass of the JMW arm is high'ish and the best cartridge matches were in the mid to low'ish compliance range. I tried to achieve a theoretical resonance (as computed off the vinyl engine website) in the 8 to 12 Hz sweet spot.

My current cartridge is a Lyra Kleos which I recall has a compliance factor of 12. There is no woofer pumping or bass ringing. IMO, it's a very good match.
rodman99999
6,160 posts
 
@Pryso- Something like this? ( http://www.freepatentsonline.com/4151998.pdf ) ( http://www.ebay.com/itm/DiscTraker-Tone-Arm-Cartridge-Damper-RARE-with-all-parts-and-instructions-/191373090757?pt=LH_DefaultDomain_0&hash=item2c8eb99fc5 )
timeltel
830 posts
 
Regards, Zavato/Pryso: Disctracker, I believe.

From 35/40 years back, lots of informative data:
http://www.bostonaudiosociety.org/pdf/bass/BASS-03-04-7501b.pdf

If you're interested in credentials, Google Lee Phoenix.

Starting on pg. 9, the practical Peter Prichard; "We really don't know quite what we're doing in this industry":
http://www.bostonaudiosociety.org/pdf/bass/BASS-04-08-7605b.pdf

Sources of resonance excitation: "The vibration input to the pickup (both signal and warp) is represented by the constant current generator exciting the circuit. The motion of the stylus assembly is modeled by the current in the CR branch, which shows that the circuit is a high-pass filter, with a resonant peak at the corner frequency."
http://shure.custhelp.com/app/answers/detail/a_id/4072#PhonoArmDamping

Thanks, Henry, for another thought provoking thread.

Peace,
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