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 6 responses by timeltel

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,
Regards, all:

Tone arm resonance can not be eliminated. It is then best positioned  where it will least likely be excited by vibrations within the mechanical system. Cantilevers and tonearms resonate at specific frequencies, damping or dumping these resonances into the system's mass are both means of addressing this phenomena but do not eliminate it in entirety. 

Apologies Henry; Parrots are in short supply but there is this:  https://www.gcaudio.com/tips-tricks/tonearm-cartridge-compatability/

"At resonance (more on this, see Kogen et al, below), the arm/cartridge combination produces a dramatic rise in output. An increase of 3 to 6dB or more is common. This tremendous boost can cause severe problems if it occurs in the region of recorded music (above 20Hz), or in the area where record warps and rumble are problematic (below 5Hz). A cartridge/arm whose resonance occurs in the region above 20Hz can be influenced by music on the record. At this frequency a significant jump in output (resulting in a "bloated" or "tubby" sound) will be experienced. In extreme cases, the stylus may actually jump out of the groove. Similarly, a cartridge/arm combination that exhibits a resonance below the desired range will exaggerate the effects of record warps, or rumble produced by the turntable."

Galen Carol cites Ortofon as a source.

==================================

Kogen et al. : Trackability 1973
"Audio" magazine, Aug. 1973. pg. 16, (excerpt, pg.19):

"The two major factors that affect the resonance frequency exhibied are determined primarily by the interaction are the mass of the tonearm and the dynamic compliance of the stylus and the efective compliance of the stylus. Increasing the mass of the tonearm-phono cartridge combination lowers the resonance frequency and tend to raise the amplitude near the resonance frequency, the motion of the stylus relative to the tonearm wil be many times that of the exciting signal. This will then significantly reduce the ability of the pickup to accurately track the grove modulation." 


"American Radio History" site. Plenty of adds for (now) vintage equipment on the way to pg.19 for those who have "been there, done that" and sufficient graphs to meet the requirements of the most demanding. 

https://www.americanradiohistory.com/Archive-Audio/70s/Audio-1973-08.pdf


Peace, 

Regards, gentlemen:

Halcro (Henry) is remarkably experienced in audio. I've trusted his impressions and continue to do so. Allow me to elaborate.

In a paper presented to the AES by Shure technician C. A. Anderson:
"resonance exists because the arm and pickup assembly behaves like an effective mass that is coupled to the record groove by means of a stylus assembly with its own mass, compliance, and mechanical resistance". Seems pretty clear, yes?

Let's take it further then:
 Ideally, frequencies BELOW the natural resonance produced by warps, eccentric groves or surface imperfections will not disturb the signal because the tonearm and cartridge move as a unit. Ideally. This occurs when compliance and mass allow the tonearm and cartridge to remain centered above the groove. Precisely what I expect of my tonearm(s).

What might our experienced listener hear ***in his system***? :  
Resonances can be considered as being constructive or destructive. When a recorded signal matches the natural resonance of our tonearm/cartridge, it's commonly accepted that the recorded signal can be enhanced by 6 to 20 dBl. Excessive excursion of the cantilever is the source, current is proportionate to stimulus and  response is the sum of mechanical and electrical properties. View either the cantilever or tonearm  as a rod, tube or beam, either will none-the-less tend to resonate at certain frequencies. At resonant frequencies the stylus tends to "scrub" in the groove. In the instance of a gross compliance/mass mismatch the entire tonearm can be seem moving laterally, sometimes leaving the groove entirely. Wow, flutter and warbling might be observed. In the instance of destructive resonances a diminution or exaggeration of signal at specific frequencies might be anticipated. Under certain system related conditions constructive resonance may (or may not) be heard as beneficial. In fewer words, "if it sounds good, it is good".

How this relates to an accurate transcripion of the media is another matter and a discussion I'll not be drawn into. None-the-less and regardless how "good" it sounds (Henry my friend), any argument that spring/mass relationships are not a consideration might be re-examined.

Looking forward to your comments &


Peace,
Regards, Halcro:

No need to respond ("Dover and the Professor will have to wait...."), it seems you already did, subsequent to Kirkus’ entry, 10-11-2014:

Halcro wrote:
"Many thanks for your thoughtful Post (as usual).....and it has made me realise how wrong I am about the importance (or lack thereof) of the Arm/Cartridge Resonance…..😲❗️
I’m really kicking myself now because I’ve done a great deal of thought and study on the subject of Structure-Borne Feedback as it relates to Audio and yet…..because I fortunately don’t suffer from it myself…..I completely ignored its possible relationship to the Arm/Cartridge Resonance..."

Two days later Fleib wrote:
"Generalizations, half truths, and oversimplification lead to erroneous conclusions even if they work. Rules are made to be broken and it’s results that matter.---
"How is it that Halcro can track almost anything with a resonant frequency below the recommended range, magic? It’s because his set-up isn’t easily excited by acoustic/mechanical impulses and he probably doesn’t play severely warped records."

Atmasphere points out "The adage that rules are made to be broken is in itself a generalization."

Offered was a thread in which the exchange of evidence and experience were deliberated in a thoughtful manner. Falling back on conventional "wisdom" is easily done, those who dare to examine certain of those conventions are not always celebrated. Mea culpa.

In this thread tunnel vision is recently in evidence, for perspective the entire thread needs to be reviewed. The title of this thread is on its own a generalization. It questions audiophile convention and stirs controversy. Although I don’t agree with all comments (ahem) I’ve been driven to actually think and for that I’m somewhat resentful.

Keep up the good work.


Peace,

Regards & pardon me, down memory lane. Uberwaltz is to blame:

BW TA & Denon 103---
First foray into "high end" audio was an Infinity BW, al. arm wand. Later models had a CF arm, damping trough optional.

For setup the user’s manual for the BW pictured a Denon 103, as did contemporary adds. Mine sat in a drawer for two years until I was finally able to afford a SP-25 TT. Hosted a Shure M95E for a while.

Son is currently running the rig with an AT 15XE on the BW. Era appropriate Kyocera integrated into rebuilt Large Advents. Sounds pretty good.


Peace,