Who needs a MM cartridge type when we have MC?


Dear friends: who really needs an MM type phono cartridge?, well I will try to share/explain with you what are my experiences about and I hope too that many of you could enrich the topic/subject with your own experiences.

For some years ( in this forum ) and time to time I posted that the MM type cartridge quality sound is better than we know or that we think and like four months ago I start a thread about: http://forum.audiogon.com/cgi-bin/fr.pl?eanlg&1173550723&openusid&zzRauliruegas&4&5#Rauliruegas where we analyse some MM type cartridges.

Well, in the last 10-12 months I buy something like 30+ different MM type phono cartridges ( you can read in my virtual system which ones. ) and I’m still doing it. The purpose of this fact ( “ buy it “ ) is for one way to confirm or not if really those MM type cartridges are good for us ( music lovers ) and at the same time learn about MM vs MC cartridges, as a fact I learn many things other than MM/MC cartridge subject.

If we take a look to the Agon analog members at least 90% of them use ( only ) MC phono cartridges, if we take a look to the “ professional reviewers “ ( TAS, Stereophile, Positive Feedback, Enjoy the Music, etc, etc, ) 95% ( at least ) of them use only MC cartridges ( well I know that for example: REG and NG of TAS and RJR of Stereophile use only MM type cartridges!!!!!!!! ) , if we take a look to the phono cartridge manufacturers more than 90% of them build/design for MC cartridges and if you speak with audio dealers almost all will tell you that the MC cartridges is the way to go.

So, who are wrong/right, the few ( like me ) that speak that the MM type is a very good alternative or the “ whole “ cartridge industry that think and support the MC cartridge only valid alternative?

IMHO I think that both groups are not totally wrong/right and that the subject is not who is wrong/right but that the subject is : KNOW-HOW or NON KNOW-HOW about.

Many years ago when I was introduced to the “ high end “ the cartridges were almost MM type ones: Shure, Stanton, Pickering, Empire, etc, etc. In those time I remember that one dealer told me that if I really want to be nearest to the music I have to buy the Empire 4000 D ( they say for 4-channel reproduction as well. ) and this was truly my first encounter with a “ high end cartridge “, I buy the 4000D I for 70.00 dls ( I can’t pay 150.00 for the D III. ), btw the specs of these Empire cartridges were impressive even today, look: frequency response: 5-50,000Hz, channel separation: 35db, tracking force range: 0.25grs to 1.25grs!!!!!!!!, just impressive, but there are some cartridges which frequency response goes to 100,000Hz!!!!!!!!!!

I start to learn about and I follow to buying other MM type cartridges ( in those times I never imagine nothing about MC cartridges: I don’t imagine of its existence!!!. ) like AKG, Micro Acoustics, ADC, B&O, Audio Technica, Sonus, etc, etc.

Years latter the same dealer told me about the MC marvelous cartridges and he introduce me to the Denon-103 following with the 103-D and the Fulton High performance, so I start to buy and hear MC cartridges. I start to read audio magazines about either cartridge type: MM and Mc ones.

I have to make changes in my audio system ( because of the low output of the MC cartridges and because I was learning how to improve the performance of my audio system ) and I follow what the reviewers/audio dealers “ speak “ about, I was un-experienced !!!!!!!, I was learning ( well I’m yet. ).

I can tell you many good/bad histories about but I don’t want that the thread was/is boring for you, so please let me tell you what I learn and where I’m standing today about:

over the years I invested thousands of dollars on several top “ high end “ MC cartridges, from the Sumiko Celebration passing for Lyras, Koetsu, Van denHul, to Allaerts ones ( just name it and I can tell that I own or owned. ), what I already invest on MC cartridges represent almost 70-80% price of my audio system.

Suddenly I stop buying MC cartridges and decide to start again with some of the MM type cartridges that I already own and what I heard motivate me to start the search for more of those “ hidden jewels “ that are ( here and now ) the MM phono cartridges and learn why are so good and how to obtain its best quality sound reproduction ( as a fact I learn many things other than MM cartridge about. ).

I don’t start this “ finding “ like a contest between MC and MM type cartridges.
The MC cartridges are as good as we already know and this is not the subject here, the subject is about MM type quality performance and how achieve the best with those cartridges.

First than all I try to identify and understand the most important characteristics ( and what they “ means “. ) of the MM type cartridges ( something that in part I already have it because our phonolinepreamp design needs. ) and its differences with the MC ones.

Well, first than all is that are high output cartridges, very high compliance ones ( 50cu is not rare. ), low or very low tracking force ones, likes 47kOhms and up, susceptible to some capacitance changes, user stylus replacement, sometimes we can use a different replacement stylus making an improvement with out the necessity to buy the next top model in the cartridge line , low and very low weight cartridges, almost all of them are build of plastic material with aluminum cantilever and with eliptical or “ old “ line contact stylus ( shibata ) ( here we don’t find: Jade/Coral/Titanium/etc, bodies or sophisticated build material cantilevers and sophisticated stylus shape. ), very very… what I say? Extremely low prices from 40.00 to 300.00 dls!!!!!!!!!!!!!!!!!!, well one of my cartridges I buy it for 8.99 dls ( one month ago ): WOW!!!!!!, so any one of you can/could have/buy ten to twenty MM cartridges for the price of one of the MC cartridge you own today and the good notice is that is a chance that those 10-20 MM type cartridges even the quality performance of your MC cartridge or beat it.

Other characteristics is that the builders show how proud they were/are on its MM type cartridges design, almost all those cartridges comes with a first rate box, comes with charts/diagrams of its frequency response and cartridge channel separation ( where they tell us which test recording use it, with which VTF, at which temperature, etc, etc. ), comes with a very wide explanation of the why’s and how’s of its design and the usual explanation to mount the cartridge along with a very wide list of specifications ( that were the envy of any of today MC ones where sometimes we really don’t know nothing about. ), comes with a set of screws/nuts, comes with a stylus brush and even with stylus cleaning fluid!!!!!!!!!, my GOD. Well, there are cartridges like the Supex SM 100MK2 that comes with two different stylus!!!! One with spherical and one with elliptical/shibata shape and dear friends all those in the same low low price!!!!!!!!!!!

Almost all the cartridges I own you can find it through Ebay and Agon and through cartridge dealers and don’t worry if you loose/broke the stylus cartridge or you find the cartridge but with out stylus, you always can/could find the stylus replacement, no problem about there are some stylus and cartridge sources.

When I’m talking about MM type cartridges I’m refer to different types: moving magnet, moving iron, moving flux, electret, variable reluctance, induced magnet, etc, etc. ( here is not the place to explain the differences on all those MM type cartridges. Maybe on other future thread. ).

I made all my very long ( time consuming ) cartridge tests using four different TT’s: Acoustic Signature Analog One MK2, Micro Seiki RX-5000, Luxman PD 310 and Technics SP-10 MK2, I use only removable headshell S and J shape tonearms with 15mm on overhang, I use different material build/ shape design /weight headshells. I test each cartridge in at least three different tonearms and some times in 3-4 different headshells till I find the “ right “ match where the cartridge perform the best, no I’m not saying that I already finish or that I already find the “ perfect “ match: cartridge/headshell/tonearm but I think I’m near that ideal target.

Through my testing experience I learn/ confirm that trying to find the right tonearm/headshell for any cartridge is well worth the effort and more important that be changing the TT. When I switch from a TT to another different one the changes on the quality cartridge performance were/are minimal in comparison to a change in the tonearm/headshell, this fact was consistent with any of those cartridges including MC ones.

So after the Phonolinepreamplifier IMHO the tonearm/headshell match for any cartridge is the more important subject, it is so important and complex that in the same tonearm ( with the same headshell wires ) but with different headshell ( even when the headshell weight were the same ) shape or build material headshell the quality cartridge performance can/could be way different.

All those experiences told me that chances are that the cartridge that you own ( MC or MM ) is not performing at its best because chances are that the tonearm you own is not the best match for that cartridge!!!!!!, so imagine what do you can/could hear when your cartridge is or will be on the right tonearm???!!!!!!!!, IMHO there are ( till today ) no single ( any type at any price ) perfect universal tonearm. IMHO there is no “ the best tonearm “, what exist or could exist is a “ best tonearm match for “ that “ cartridge “, but that’s all. Of course that are “ lucky “ tonearms that are very good match for more than one cartridge but don’t for every single cartridge.

I posted several times that I’m not a tonearm collector, that I own all those tonearms to have alternatives for my cartridges and with removable headshells my 15 tonearms are really like 100+ tonearms : a very wide options/alternatives for almost any cartridge!!!!!!

You can find several of these MM type cartridges new brand or NOS like: Ortofon, Nagaoka, Audio Technica, Astatic, B&O, Rega, Empire, Sonus Reson,Goldring,Clearaudio, Grado, Shelter, Garrot, etc. and all of them second hand in very good operational condition. As a fact I buy two and even three cartridges of the same model in some of the cartridges ( so right now I have some samples that I think I don’t use any more. ) to prevent that one of them arrive in non operational condition but I’m glad to say that all them arrive in very fine conditions. I buy one or two of the cartridges with no stylus or with the stylus out of work but I don’t have any trouble because I could find the stylus replacement on different sources and in some case the original new replacement.

All these buy/find cartridges was very time consuming and we have to have a lot of patience and a little lucky to obtain what we are looking for but I can asure you that is worth of it.

Ok, I think it is time to share my performance cartridge findings:

first we have to have a Phonolinepreamplifier with a very good MM phono stage ( at least at the same level that the MC stage. ). I’m lucky because my Phonolinepreamplifier has two independent phono stages, one for the MM and one for MC: both were designed for the specifics needs of each cartridge type, MM or MC that have different needs.

we need a decent TT and decent tonearm.

we have to load the MM cartridges not at 47K but at 100K ( at least 75K not less. ).

I find that using 47K ( a standard manufacture recommendation ) prevent to obtain the best quality performance, 100K make the difference. I try this with all those MM type cartridges and in all of them I achieve the best performance with 100K load impedance.

I find too that using the manufacturer capacitance advise not always is for the better, till “ the end of the day “ I find that between 100-150pf ( total capacitance including cable capacitance. ) all the cartridges performs at its best.

I start to change the load impedance on MM cartridges like a synonymous that what many of us made with MC cartridges where we try with different load impedance values, latter I read on the Empire 4000 DIII that the precise load impedance must be 100kOhms and in a white paper of some Grace F9 tests the used impedance value was 100kOhms, the same that I read on other operational MM cartridge manual and my ears tell/told me that 100kOhms is “ the value “.

Before I go on I want to remember you that several of those MM type cartridges ( almost all ) were build more than 30+ years ago!!!!!!!! and today performs at the same top quality level than today MC/MM top quality cartridges!!!!!, any brand at any price and in some ways beat it.

I use 4-5 recordings that I know very well and that give me the right answers to know that any cartridge is performing at its best or near it. Many times what I heard through those recordings were fine: everything were on target however the music don’t come “ alive “ don’t “ tell me “ nothing, I was not feeling the emotion that the music can communicate. In those cartridge cases I have to try it in other tonearm and/or with a different headshell till the “ feelings comes “ and only when this was achieved I then was satisfied.

All the tests were made with a volume level ( SPL ) where the recording “ shines “ and comes alive like in a live event. Sometimes changing the volume level by 1-1.5 db fixed everything.

Of course that the people that in a regular manner attend to hear/heard live music it will be more easy to know when something is right or wrong.

Well, Raul go on!!: one characteristic on the MM cartridges set-up was that almost all them likes to ride with a positive ( little/small ) VTA only the Grace Ruby and F9E and Sonus Gold Blue likes a negative VTA , on the other hand with the Nagaoka MP 50 Super and the Ortofon’s I use a flat VTA.

Regarding the VTF I use the manufacturer advise and sometimes 0.1+grs.
Of course that I made fine tuning through moderate changes in the Azymuth and for anti-skate I use between half/third VTF value.

I use different material build headshells: aluminum, composite aluminum, magnesium, composite magnesium, ceramic, wood and non magnetic stainless steel, these cartridges comes from Audio Technica, Denon, SAEC, Technics, Fidelity Research, Belldream, Grace, Nagaoka, Koetsu, Dynavector and Audiocraft.
All of them but the wood made ( the wood does not likes to any cartridge. ) very good job . It is here where a cartridge could seems good or very good depending of the headshell where is mounted and the tonearm.
Example, I have hard time with some of those cartridge like the Audio Technica AT 20SS where its performance was on the bright sound that sometimes was harsh till I find that the ceramic headshell was/is the right match now this cartridge perform beautiful, something similar happen with the Nagaoka ( Jeweltone in Japan ), Shelter , Grace, Garrot , AKG and B&O but when were mounted in the right headshell/tonearm all them performs great.

Other things that you have to know: I use two different cooper headshell wires, both very neutral and with similar “ sound “ and I use three different phono cables, all three very neutral too with some differences on the sound performance but nothing that “ makes the difference “ on the quality sound of any of my cartridges, either MM or MC, btw I know extremely well those phono cables: Analysis Plus, Harmonic Technologies and Kimber Kable ( all three the silver models. ), finally and don’t less important is that those phono cables were wired in balanced way to take advantage of my Phonolinepreamp fully balanced design.

What do you note the first time you put your MM cartridge on the record?, well a total absence of noise/hum or the like that you have through your MC cartridges ( and that is not a cartridge problem but a Phonolinepreamp problem due to the low output of the MC cartridges. ), a dead silent black ( beautiful ) soundstage where appear the MUSIC performance, this experience alone is worth it.

The second and maybe the most important MM cartridge characteristic is that you hear/heard the MUSIC flow/run extremely “ easy “ with no distracting sound distortions/artifacts ( I can’t explain exactly this very important subject but it is wonderful ) even you can hear/heard “ sounds/notes “ that you never before heard it and you even don’t know exist on the recording: what a experience!!!!!!!!!!!

IMHO I think that the MUSIC run so easily through a MM cartridge due ( between other facts ) to its very high compliance characteristic on almost any MM cartridge.

This very high compliance permit ( between other things like be less sensitive to out-center hole records. ) to these cartridges stay always in contact with the groove and never loose that groove contact not even on the grooves that were recorded at very high velocity, something that a low/medium cartridge compliance can’t achieve, due to this low/medium compliance characteristic the MC cartridges loose ( time to time and depending of the recorded velocity ) groove contact ( minute extremely minute loose contact, but exist. ) and the quality sound performance suffer about and we can hear it, the same pass with the MC cartridges when are playing the inner grooves on a record instead the very high compliance MM cartridges because has better tracking drive perform better than the MC ones at inner record grooves and here too we can hear it.

Btw, some Agoners ask very worried ( on more than one Agon thread ) that its cartridge can’t track ( clean ) the cannons on the 1812 Telarc recording and usually the answers that different people posted were something like this: “””” don’t worry about other than that Telarc recording no other commercial recording comes recorded at that so high velocity, if you don’t have trouble with other of your LP’s then stay calm. “””””

Well, this standard answer have some “ sense “ but the people ( like me ) that already has/have the experience to hear/heard a MM or MC ( like the Ortofon MC 2000 or the Denon DS1, high compliance Mc cartridges. ) cartridge that pass easily the 1812 Telarc test can tell us that those cartridges make a huge difference in the quality sound reproduction of any “ normal “ recording, so it is more important that what we think to have a better cartridge tracking groove drive!!!!

There are many facts around the MM cartridge subject but till we try it in the right set-up it will be ( for some people ) difficult to understand “ those beauties “. Something that I admire on the MM cartridges is how ( almost all of them ) they handle the frequency extremes: the low bass with the right pitch/heft/tight/vivid with no colorations of the kind “ organic !!” that many non know-how people speak about, the highs neutral/open/transparent/airy believable like the live music, these frequency extremes handle make that the MUSIC flow in our minds to wake up our feelings/emotions that at “ the end of the day “ is all what a music lover is looking for.
These not means that these cartridges don’t shine on the midrange because they do too and they have very good soundstage but here is more system/room dependent.

Well we have a very good alternative on the ( very low price ) MM type cartridges to achieve that music target and I’m not saying that you change your MC cartridge for a MM one: NO, what I’m trying to tell you is that it is worth to have ( as many you can buy/find ) the MM type cartridges along your MC ones

I want to tell you that I can live happy with any of those MM cartridges and I’m not saying with this that all of them perform at the same quality level NO!! what I’m saying is that all of them are very good performers, all of them approach you nearest to the music.

If you ask me which one is the best I can tell you that this will be a very hard “ call “ an almost impossible to decide, I think that I can make a difference between the very good ones and the stellar ones where IMHO the next cartridges belongs to this group:

Audio Technica ATML 170 and 180 OCC, Grado The Amber Tribute, Grace Ruby, Garrot P77, Nagaoka MP-50 Super, B&O MMC2 and MMC20CL, AKG P8ES SuperNova, Reson Reca ,Astatic MF-100 and Stanton LZS 981.

There are other ones that are really near this group: ADC Astrion, Supex MF-100 MK2, Micro Acoustics MA630/830, Empire 750 LTD and 600LAC, Sonus Dimension 5, Astatic MF-200 and 300 and the Acutex 320III.

The other ones are very good too but less refined ones.
I try too ( owned or borrowed for a friend ) the Shure IV and VMR, Music maker 2-3 and Clearaudio Virtuoso/Maestro, from these I could recommended only the Clearaudios the Shure’s and Music Maker are almost mediocre ones performers.
I forgot I try to the B&O Soundsmith versions, well this cartridges are good but are different from the original B&O ( that I prefer. ) due that the Sounsmith ones use ruby cantilevers instead the original B&O sapphire ones that for what I tested sounds more natural and less hi-fi like the ruby ones.

What I learn other that the importance on the quality sound reproduction through MM type cartridges?, well that unfortunately the advance in the design looking for a better quality cartridge performers advance almost nothing either on MM and MC cartridges.

Yes, today we have different/advanced body cartridge materials, different cantilever build materials, different stylus shape/profile, different, different,,,,different, but the quality sound reproduction is almost the same with cartridges build 30+ years ago and this is a fact. The same occur with TT’s and tonearms. Is sad to speak in this way but it is what we have today. Please, I’m not saying that some cartridges designs don’t grow up because they did it, example: Koetsu they today Koetsu’s are better performers that the old ones but against other cartridges the Koetsu ones don’t advance and many old and today cartridges MM/MC beat them easily.

Where I think the audio industry grow-up for the better are in electronic audio items ( like the Phonolinepreamps ), speakers and room treatment, but this is only my HO.

I know that there are many things that I forgot and many other things that we have to think about but what you can read here is IMHO a good point to start.

Regards and enjoy the music.
Raul.
Ag insider logo xs@2xrauliruegas
Dear Lewm: Till today I'm still " married " with 100K and I don't tryed ( yet ) a higher one, Dgarretson can help you here because he has a impedance load selector for as higher as 250K and I assume he already tryed higher than 100K loads.

In my set up these are the added load capacitance values that I use with some cartridges:

AT ML-180 OCC: 50pf. , Micro Acoustics MA-630: 400pf, Technics 205CMK4: 350pf, Sonus Dimension 5: 350pf, Signet TK10MLII: 150pf, Nagatron 9600: 100pf, Excel ES70XE4: 450pf, Micro Seiki LF-7: 150pf, ADC 25: 450pf and Empire 750LTD: 300pf.

My advise is that if you can leave capacitance alone and independent on the impedance selector.

Those cartridge capacitance loads were " found out " after several tests with several capacitance values, I don't found out a " rule " for this subject ( other that the process I follow to do it. ) where everything were made through my ears " measure tool ".

I'm using the cartridge capacitive load as a critical and very important way for a cartridge " final fine tunning ", said " final " means that we have to take care in deep on these capacitance load changes: not so easy as it " sounds " but when you made the " right " capacitance load cartridge set up you know immediately that that load is " right " against other values. IMHO we need a " process " that can works for each one of us. Till today mine always works and tell me what's happening and what's not happening.

IMHO the cartridge capacitance load subject not only is critical ( maybe more than load impedance ) but makes a paramount difference if the audio system has the resolution for you be aware of those differences.

Good that you are taking care on the whole cartridge load capacitance/impedance subject, good luck.

Regards and enjoy the music,
Raul.
Dear Lewm: Obviously that the " right " impedance/capacitance cartridge set up depend mainly on how good is the overall cartridge/tonearm set up, this tonearm/cartridge set up is the main step ( critical one. ) for you can achieve the best of " that " cartridge performance. The other important subject is with which tonearm/headshell the cartridge is mated.

Regrads and enjoy the music,
Raul.
Regards, Raul: It was a dark and stormy night-.

N120HE: Nude Hyperelliptical .0002 x .0015", alu. telescoped shank cantilever.
N140HE: Nude HE .0002 x .0015 microwall/Be cantilever.
Tracking, 1.00gm optimal, 1.25 max. Add .5gm if stabilizer brush is down.
Shure didn't do Shibata, they called it "HE" instead.

The 140 stylus was found eighteen or so months ago, the cartridge about a year ago. The 120 stylus several months later. Distracted by the Acutex then an exploration of the Signet carts, the ML140HE rested in a headshell until your mention several weeks ago.

It was a dark/stormy night, so out came the 140, with the N120 stylus still mounted. Hey, this sounds much better than I remembered. Two sides later the N140 stylus was installed.

Rivets sizzling in the cymbols, check. Tambourine, the percussive impact and initial clatter of the zils, check.
Violin, strings have that woody resonance, the rasp of the bow, check. Woodwinds reedy, flutes overblown, check. Brass, electronica, keyboards yep, they're all there and well behaved, no pushing/shoving/confusion/crowding, check.

Bass? Resolved and defined, initial attack to the point of atmospheric concussion, then lingering with the note as it modifies/moderates, convincingly aggressive without distraction. And tonality, neutral without loosing immediacy, voice is natural, did I mention the quality of the bass?

It was a dark and stormy night but as you promised a review of the cartridge, I thought to, rather than take the wind from your sails to just trim the rigging in advance.

The only question I have about the Shure is will you choose to report or find it meritorious of a "formal" review.

On the application of capacitance you wrote: "I'm using the cartridge capacitive load as a critical and very important way for a cartridge " final fine tunning ", said " final " means that we have to take care in deep on these capacitance load changes: not so easy as it " sounds " but when you made the " right " capacitance load cartridge set up you know immediately that that load is " right " against other values." Totally agree. Some might say the same for varying resistance.

Peace,
Thanks, Timeltel, Raul, and everyone for your interesting responses. I must say I am surprised at the (high-ish) amount of capacitance Timeltel has found to be optimal with various different cartridges. Also, as regards the inherent capacitance at the input, we must also consider Miller capacitance. Here or elsewhere I was recently reminded that Miller is equal to the sum of the plate to grid and grid to cathode C multiplied by the gain, for a common cathode tube input and probably also for a standard analogous transistor input, that can add a fair amount to the 75pF we allocate for cables. So I have to ask Timeltel whether he uses tube or solid state phono and what brand. (Pentode or cascode input shields the grid from Miller effect, so there we do not have much input capacitance due to Miller.) What type of load C sounds best: polystyrene or silver mica? The latter seem to be popular these days for use in RIAA equalization. I only wish I had room for two rotary switches, one for load R and one for load C. Won't fit.
Regards, Lew(m): Scientist! Anyway and again, but since it's you: 100% SS, I happen to prefer neutrality to "romantic". Overly analytical or bloated don't turn my crank either. YMMV.

Phono stage is FET followed by RIAA eq. to within 0.02dB, arrayed in a cascade-connected three stage direct coupled complementary SEPP design. THD is -0.03%. Short circuited, hum and noise is 87dB. I hope this is O.K. with you?

Lew, my element of surprise is in the other direction, in that from the nature of your post the apperance is that you consider typical working cap. to be less than 200pF?

Reco. cap. for the Azden YM-P50VL, 100-300 pF. ADC XLM-11 is 275 pF, the AKG p8E, 400. Empire 200Z: 300. Ortofon VMS20: 400. And, of course, the Shure V15-111, 400-500, as are many other Shure Cartridges. These are mfg. figures, documented and available with a minimum of research.

Cruise through the listed recommendations given in VE's cartridge databank for cartridges with output in the 1.5 - 3.5mV range. When given, capacitance loading will be anywhere from 100 - 500 pF. For those above 3.5mV output, it's much the same. In the higher output group, the general tendency is for AT associated cartridges at a recommended 100 - 200 pF, Ortofon and Shures from 300 to 500.

Stanton and Pickering apparently decided on a compromise, settling on a nearly universal 275 pF a typical capacitance for consumer grade decks in the '70's. This is why many had soldered-in connectors (and p-mount tonearms), it detered the average homeowner/listener from making uninformed modifications.

If you find reason to vary from well established loadings be my guest. I'd not presume to critique from a "remote listening" to your system and you have no one to suit but yourself. If, on the other hand, it should give you something to consider then I'm pleased to have shared the information.

Peace,
Regards, Lew(m), and an addendum. There was something about your post that kept nipping at my attention. I finally realized it was your reference to the Miller effect, which would indeed explain why you might find a lower shunted capacitance preferable to mfr. (or typical) applications. Such considerations are just one more factor to take into account when communicating, sometimes it seems if one asks a question of two audiophiles, expect three answers.

I'm confident that after the prerequisite agonizations and sufficient propitiation to the deities of the electron, you'll resolve this to your satisfaction.

Peace,
Dear Timeltel,
What's up? First of all, I made no statement about a preference of tubes vs solid state. As I am sure you know, ss gain devices have Miller capacitance too. I was only discussing Miller capacitance. I happen to own an Ayre p5Xe as well as an Atma-sphere MP1, and I like them both. In fact I also modified the input stage of the phono section of my MP1 to a hybrid cascode, with an MAT02 bipolar transistor on the bottom and an ECC99 vacuum tube on top, to get more gain and less noise vs the all-tube stock circuit. The amount of phono gain I have now is staggering. Even the lowest output Ortofon MC does not strain the system. Unfortunately, there is TOO much gain for most MMs, even when I cut back the gain by a little trick inside the dual-differential cascode topology. Thus I am using the Ayre for MM/MI cartridges. I am still trying to figure out where it was that I may have dissed transistors. I don't love them per se, but I don't dismiss or disrespect them either. By the way, the selector switch I am going to install is for a third (all-tube) phono stage I just bought, because it is kind of a legendary piece, out of production for 10 years. I am going to see if it can be made to outperform the Ayre with MM/MI cartridges.

As to my expression of surprise at the amount of added capacitance you suggested, it was only that - surprise. I in no way meant to indicate disagreement, because I have no opinion on this subject. Even if I did, opinion does not count where there are facts available. You are correct in pointing out that I did not do my homework by consulting tables apparently available on VE. That is because I did not know such tables were available. Had I done so, I probably would not have been surprised to read your recommended load parameters. Meantime, thanks for the factual input in your previous post. I take your guidance in this matter seriously. But there is no need to get into a tete a tete on tubes vs transistors.
Dear Lewm, indeed. It's not tube vs transitors. Both can deliver top results. One can design a solid state preamp to sound romantic and "tubey" (ever heard an original Kaneda ss ? More romantic sound than you will ever hear from any tube based design). And there are triode and pentode preamps out there delivering ultra clear and super low distortion ( and only 2nd harmonic if at all) sound.
It is always about good design vs bad design.
Designing audio components is not a religion and it is not about a "camp".
Cheers,
D.
Dear Dertonarm, If your argument is valid why should
anyone, except the masogist, buy a tube anything?

Regards,
Dertonearm, I completely agree with every word you wrote. I also think that verbal arguments on the subject of tubes v transistors are about as worthwhile as arguing about one's religion vs another's. That's why I never intended to "go there". I am not sure I understand Timeltel's last sentence, but I hope he gets the point. Enough said. Apologies all around.

Now I have to go back and see what Nicola wrote.
Nandric, You are reviving the argument. Bad. I will give you one surprisingly pragmatic reason why I generally prefer tube equipment: I know enough about it to build and repair it myself. I will leave out the other reasons while also insisting that I have shown in practice (Parasound amp and Ayre phono stage) that I am not at all close-minded when it comes to solid state. If it's good, it's good.

Timeltel, I guess there may be another term (i.e., other than "Miller") to describe the natural input capacitance of a solid state device, but it does exist. And I think it's even of a magnitude not terribly different from that of a vacuum tube used in a gain stage. That's all I was talking about above.
Dear Lew, I am realy sorry; I thought that the argument was
about the sound. Regarding pragmatics one can also mention:
no need for a heating system and also add some aesthetical
argument like the beauty of the tubes glow.

Regards,
Dear Lewm: I forgot that I loaded the great Azden P50VL with added 250pf.

Btw, I writed " great " because today the " emotions " surrounded me ( again ) in the last two days that I decided to try it again, all I can say is: WHAT A PHENOMENAL PERFORMER, yes with capital letters.

I did not heard the Azden for at least 12 months ( when was the month's cartridge. ) now and its great quality performance along that my SLFL goes really lower through that time now this cartridge is showing me things that I was unaware the Azden could do it. This IMHO is a cartridge that honored MUSIC and honored any " best " audio system out there.

Now, I'm not sure which cartridge I will make a " formal " review because I have other cadidates ( including the Shure M140HE ) but I'm taken by this Azden.
Halcro, pity that your sample is out of work/specs because IMHO this could be the " top dog " in your cartridge arsenal.

Lewm, I think that if you can't have two independent selectors for impedance and capacitance then ( after a test between 47k and 100k in that tube phono stage. ) your choice could be a fixed impedance ( either: 47k or 100k. ) with all the capacitance value options you decide.

Regards and enjoy the music,
Raul.
Hey, Lew: Most sincere apologies if anything written offered offense, your post was (obviously) wholly in the information seeking mode. My "last sentence" was just a reflection that without being able to become personally acquainted with your outfit, there was no way in which I could give meaningful input.

The figures relating to "recommended" capacitance only a matter for reflection. Hell, I fiddle with cap./res. to my own satisfaction, I'm entirely convinced there's so much going on in mechanical influences relating to harmonics that adhereing with exactitude to the Nth pF can be counterproductive, shutting off one's ears to spite one's own pFace, so to speak.

No argument here with tubes/SS either. "No one to please but yourself". To paraphrase a much more knowledgable recent contributor, character is flexible in either arena. It would be either chauvenisticaly unmannerly or a demonstration of ignorance to suggest otherwise. I'll confess to an abundance of breaches of both.

Most sincerely, Peace.
Timeltel, I think you are channeling the great Ricky Nelson who famously sang,
"Ya can't please ev'ry-one
so ya... got to pleeze your-self."

Nandric will recognize Ricky Nelson's lament in relation to Kant's categorical imperative.

Raul, Could be I misjudged the Azden due to lack of capacitance. I will re-visit it with my "new" old pre-amp. But I am still quite happy with Acutex and Stanton.
Dear Lewm: Like you I'm im´ressed by the Acutex but this does not means that the Azden is a winner too.

For what I remember you always had some kind of " problems " with your Azden, I mean not a real problem but things not goes fine with the Azden in your system. Anyway, like you say a re-visit is in order and maybe this time you will have a better " luck " with.

Regards and enjoy the music,
Raul.
Yeah, the Azden was never quite happy with me. I was about to sell it, in fact. My long term goal is to whittle down this "collection" of MM/MI cartridges to 3 or 4 that really float my boat the most.
Lew(m): Good ol' Rick. "You see, you can't please everyone, so you got to please yourself". I think you've got this out of context. When this was written Nelson was somewhat bitter regarding the reception given his new work when presented in concert at Madison Square Garden. The audience in attendance had expected his teen idol hits, Nelson was booed because he didn't accede. The song "Garden Party" was his response, it was intended as a condemnation of his audience's failure to progress with his artistic maturation. This went over the heads of most, millions bought the very record that castigated them for their own anachronisms.

"If you gotta' play at garden parties, I wish you a'lot of luck, but if memories were all I sang, I'd rather drive a truck".

Catagorical imperative: "Act only according to that maxim whereby you can, at the same time, will that it should become a universal law." Totalitarianism is just not my cup o' tea. I also seem to be somewhat allergic to universalities or absolutes as universal claims can never be verified. Absolute imperatives are a different concern. Otherwise, Kant is not currently fashionable.

The rougish Voltaire is my man: "I disapprove of what you say, but I will defend to the death your right to say it". Hence, in extrapolation and in support of the archaic notion that a rational (important qualifier) man has the right to surround himself with articles of his own choosing and according to his own taste, I'll repeat: YMMV.

Thanks for providing an opportunity to improve the quality of discourse.

Peace.
Timeltel,

Does your interpretation of the categorical imperative (vis, Totalitarianism) hold and, if so, how does that sit with its role in Kant's critique of the Wolffians?

I would imagine that that form of political atemporal rationalism is rather anti-Kant! Not sure.
Timeltel,

Sorry to place my own uncertainties here but I feel that a statement such as: "universal claims can 'never' be verified" would form a starting point for the exploration that Kant develops across the three Critiques and associated writings.

Just thought I might follow out of context for a final time to share my uncertainties here.
Dear Timeltel, I am not sure what you mean by 'universal claims' but to my mind those are not different from the so called 'universal quantification' in the logic of quantification. Even Tarskis theory of truth is in terms
of satisfaction conditions.
BTW Kant was an ordinary sitezen so not realy in the position to prescribe anything to anyone. Ie all kinds of
prescriptions were Kings prerogitive while his autority was
firmly grounded by appointment by the Allmighty.
But I agree reg. Voltaire.
Addendum, Those satisfaction conditions may need some
illustration. If, say, Dertonarm is the only German with
the sence for humour then you are not allowed to 'claim'
the universal statement 'all Germans lack the sence for
humour' as true. Ie the condition 'all' is not satisfied.
Exactly the same method is used by Sir Karl (Popper) in order to explain his theory of refutation. At some phylosopher congress he first pronunced the universal statemet 'all swans are white' and then pulled a single
black swan from his hat wich he brought from Australia for
the occasion. The phylosopher are very suspicious in particular against each other so the most of them wanted to
check and see with their own eye if this swan was not painted black. Even some from Australia.
The Dertonarm case may seem somhow enbarrassing for the Dutch but they invented their own 'deviant logic' called
intuitionist logic. Invented by Brouwer obvously because he
had something against Kant and Frege (both of them Germans).

Regards,
Dear Lewm: I can see your point. I have 10+ cartridges that " float my boat " and counting.

Lewm, as your system quality performance improve and your ASLFL goes down as more cartridges you will find " float your boat ".
Maybe your first " move " could be to achieve that quality performance level before you put on sale any of the cartridges you own.

Regards and enjoy the music,
Raul.
Regards, all and thanks for your comments. Pleased to see movement in the thread as Lew's reference to Ricky Nelson has resulted in the verse running constantly through my mind.

Dgob: As I remember, Kant was a believer in moral duty. The refered to "maxim" implies external compulsion whereas absolute imperatives are internal, such as food, water, music. "This is what I want and to gain my objective, I must perform these acts". The presupposition is that all rational humans should be able to conclude the same moral laws. The difficulty with the application of categorical imperatives relates to the circumstance that there are those who would presume to ignore Kant's position that human beings are not to be used as a means to an ends. Kant makes a distinction between duty and inclination, there are those who, historically, seek to assert their "will" on others and impose "universal law" regardless of the consideration of contradictory moral dilemas. Rousseau takes a different tact, that of the social contract and "volunte' generale", which meets it's own demise in excessive application resulting in a "popular totalarianism". From "Discourse On Inequality": "From how many crimes, wars, and murders, from how many horrors and misfortunes might not any one have saved mankind, by pulling up the stakes, or filling up the ditch,----the fruits of the earth belong to us all---." I prefer Aristotle's company. Unfortunately the sage is also not currently in vouge.

Most esteemed Nikola: Regarding universalities, I can only say that in my humble and limited existence, I've yet to encounter a recognized example. Permit my refuge in another of Voltaire's observations: "Doubt is not a pleasant condition, but certainty is absurd". I have a cat named Schrödinger.

A matter of curiosity provoked by communication with another. Most headshells are provided with a rubber o-ring where the shell joins the collet, some recommend it's removal. Would doing so result in a "universal" improvment, or is it a situational condition?

Peace,
Dear Timeltel, The 'moral duty' seems to be time dependant.
'Your' Aristoteles wrote an editorial about the question
'how should we treat our slaves'. If you read not some but the most statements of Kant about woman you will not believe your own eyes. So much for his moral. Regarding
the logic of quantification I don't believe you got this
right. It is not about 'certainty' but about condidions
and those are usuly preceded with the hypothetical 'if'.
This small expression is usualy overlooked so I got a reprimand from Lew in connection with the tubes. My quess
precluded with 'if' was that they may be not practical.
And then I was so glad to pass the first control...

Regards,
Timeltel,

"There are those who would presume to ignore Kant's position".

Without a doubt true and Kant would maintain that these presumptions hold no sway as universal - his Groundwork clearly set against such presumptions.
Dear Timeltel: That headshell O-ring can give you some kind of " damping " when you need it.
It works?, this is something that only you can tell when you try it in your system because sometimes can works and sometimes don't/did not.

Other than " damping " you could use it to make minute/tiny changes on overhang even you can use more than one O-ring in the same headshell.

Regards and enjoy the music,
Raul.
Amidst all the philosophy, Timeltel does a nice segue into headshell 'O' rings?
I know Fidelity Research supplies none with their headshells and tonearms and even go to lengths to advise users of other headshells with FR arms to remove the 'O' rings.
I have just received a Yamamoto HS-1AS African Wood headshell which surprisingly also does not include an 'O' ring?
I have my views based on science and engineering principles but I am willing to believe that some will have experiences with tonearms and cartridges that appear to benefit from the 'O' ring?
Perhaps a new thread is warranted to discuss our experiences with various headshells........not limited to 'O' rings alone?
As MC is mentioned at the same time as MM in the subject of this ubiquitous thread, I think it is fair enough to compare some of the great MC cartridges to those newly discovered wonders of the vintage MM era?
It certainly could give some 'reference' to those who have not heard (or cannot hear) the vintage and somewhat scarce MM cartridges that some of us have been fortunate enough to acquire?

Let me begin with the legendary Fidelity Research FR-7f LOMC cartridge first designed by Ikeda San as the FR-7 in 1978.
FR-7f
I was fortunate enough to recently acquire one of these rare and expensive cartridges albeit without a usable stylus.
With the help of Dertonarm and his man in Tokyo who originally worked with Ikeda San, I have a brand new spherical stylus.

Now over the last 12 years I've had about 9 or 10 of the best LOMC cartridges including the Koetsu Urishi, Lyra Helikon and Titan i, Clearaudio Insider Gold and Dynavector XV1s.
I found the ZYX Universe to be the most satisfying and 'realistic' of all those I heard in my system but compared to all the 'new' MM cartridges I've acquired in the last 9 months, the majority of these LOMCs seemed to have a serious deficiency in handling complex orchestral fortissimi and poorly recorded electronic overloads, whereby a peculiar 'distortion' on such passages often rendered them unlistenable or at least painful?
The FR-7f is the first LOMC I've heard in my system to suffer none of those affects and in many ways is far more akin to the very best MMs in that respect.
After allowing nearly 30 hours of listening time for the new stylus to 'break-in', the sound of the FR-7f in the FR-66s tonearm on the Raven AC-3 is as neutral and 'realistic' in my system, as the infamous Technics EPC100Mk3 MM cartridge in my Grace 940G on my 'nude' Victor TT-81.
As such, it may be called a 'reference' and for the life of me, I can find little to criticize in any of its performance.
But just as the Technics can be admired for ITS reference-standard performance..........I don't really LOVE the EPC100Mk3?
And so I can't really LOVE the FR-7f.
Admire?........absolutely.
But you really need a cartridge that 'MOVES' you as well IMO. One that makes you forget you're listening to a collection of electronics and simply reaches within to a place where reality is suspended and emotion takes hold.
And for me, that is in the realm of the Empires 1000ZE/X and D4000/III, the FR-5 and FR-6SE, the AT-155LC and the Signets TK-3, TK5 and TK-7.
That's at least 8 MM cartridges that I put ahead of the finest LOMC I have ever heard?
YMMV
Halcro,

Please feed back on the performance of the Yamamoto once you've fully familiarised yourself with it. I have always avoided wooden headshells (and equipment in general) due to fears about potential natural and climate induced anomalies.
Regards, Nandric: "Certianty": There are those who contend that in order to adequately describe events one must take into consideration the context of the social conditions at the time of the occurance. This seems to be a matter of convenience rather than consistency. Another free-thinker, Thomas Jefferson, also experienced the confusions of contradictory moral dilemas.

Dgob: "Ay, there's the rub". Thank you for your generous restraint. The consequences of "cherry picking" the thoughts of great men can be used to justify such as the Commitee of Public Safety, Robespierre and a certain Austrian painter. Having committed the same offence, I hope to not suffer their (or Hamlet's) fate at the hands of yourself and Nandric the Terrible. The question was put forth by another, I've still not been able to determine the extent of Kant's influence on Ricky Nelson and the author of that post isn't elaborating. To do so would probably require considerable effort for little purpose. None the less, of the two quotations offered, the implications of one I find frightening, the other absurd. Your responses and positions have been immaculate and precisely to the point. Please consider anything I've written as intentionally controversal. Bad dog!

Raul, regards: I've tried both ways (with/without o-ring), you've described it perfectly. I see (Halcro) Henry has opened a thread on the subject of headshells, this should be informative.

While still on the subject of headshells, I have a vauge rememberence of an article from the mid '70's, a comparison of straight vs. "J" or "S" shaped arms. I wish I could retrieve it but (IIRC) the conclusion was that although there might be a negative consequence from the added connection with a detachable headshell, the curved tonearms were offered after research showed such a shape resulted in lowered distortion across the recording. Would you or any other mathmatically gifted person have any information/opinion about this?

From the few stolden glimpses of your tonearm, it appears to be a thing of beauty.

Peace,
Will do Dgob,
But probably best to do it on the new thread Removable Headshells 101?
Dear Halcro: IMHO it is worth that you try some way to bring your Azden to work. It is a facinating performer and I'm sure you will include it in the cartridges you MOVE.

I'm testing it in the G-940 with Grace headshell and I'm doing not in direct-connection fashion but using the adaptor pin connectors.

I would like that other Azden P50LV owners could test again this cartridge and share " new " experiences about ( if any. ) because with my cartridge sample everything improved over the first time I tested, that if I remember was with the same tonearm.

Regards and enjoy the music,
Raul.
Dear Raul,
If I could resurrect the Azden from the crumpled mess left by my steel-capped hunting boots, it would be more miraculous than the resurrection of Lazarus? :-))
Dear Dgarretson/Lewm: Do you already have the time to test again the AT 20SS and the Azden one?, thank you in advance for share your experiences.

Btw, I'm testing the 20SS ( again ) loaded with 350pf, very promising.

Regards and enjoy the music,
Raul.
Dear Timeltel: What a hell!. From the very first time you mentioned the headshell O-ring I start to testing some cartridges with and with out that rubber O-ring and at least with the ones I did it the veredict is: leave the O-ring in place where belongs, with the headshell as an important and critical link with the tonearm.

I think Iwill follow making tests on the subject a see what experiences could achieve.

Regards and enjoy the music,
Raul.
Regards, Raul: Thank you for the follow-up. Your previous "depends" statement still stands but in my experience (ancient rig/ears etc.) response without the o-ring seems to gain a glassy quality. Psychoacoustic? I really don't think so. Headshell dependent? Perhaps Henry would be so obliging as to comment on differences when tried both ways with his Yama. wooden shell.

Perhaps Will Rogers' observation applies: "There are three kinds of men. The one who learns by reading, the few who learn by observation. The rest of them have to pee on the electric fence for themselves". In this instance it may be best to suggest the experiment. Removing the o-ring, that is.

Peace,
Dear Timeltel: Not only glassy but less natural overall presentation but you only be aware when compare it because if not then with out O-ring things " can be fine ".

Now, that's what I experienced through: AT 20SS, Micro Acoutics MA-630, Azden P50VL, Empire 750LTD and ADC 25. I can't be sure if that is true with other cartridges. Things are that time ago I decided to go " naked " and only a few weeks ago I return to the O-ring.

Headshell dependent?, I can't be sure either but all those cartridges I named are mounted in different headshells so ?!?!???

We need to test each time and decide about.

Regards and enjoy the music,
Raul.
Why don't you try replacing the headshell gasket with a thin sheet of lead, or a short piece of wire solder (not of the lead-free type) formed into a ring of suitable dimensions. Likewise worthwhile is a short piece of copper wire (not of the tough-pitch type, and preferably soft-annealed). In fact, audiophiles in Japan during the late 70s ~ early 80s could buy replacement gaskets which (AFAIR) were a three-layer laminate of lead-copper-lead.

Another weak point to address with universal headshells is the electrical contact between headshell and tonearm. Since these contacts are non-wiping, oxides and contamination can and will build up on the contact surfaces. Periodically lightly buffing the contact points on both the headshell and inside the tonearm (Supex used to sell a tool specifically for the purpose) will give the sound more vividness, dynamic contrast and resolution.

You don't want to buff the contacts of your vintage tonearm/headshell too hard, however, since the vast majority are plated with gold (at best), rather than harder and more durable materials like rhodium or platinum.

IME, however, degraded contact quality affects cartridges with high output voltages less than cartridges with low output voltages (the same can be said about multiple contacts in series, like those in universal headshell tonearms).

hth, jonathan carr
replacement gaskets which (AFAIR) were a three-layer laminate of lead-copper-lead.
Oh how I wish these were still available?
The problem with rubber gaskets is that rubber, of course, allows movement....or as Raul calls it....."damping"????
But 'movement' is the last thing one wants in the cartridge/arm/table interface as this means 'lost information'. Where else in the cartridge/tonearm/table coupling would anyone expect to see rubber?
The only way to minimise this 'movement' with the rubber, is to tighten the locking collar with enough torque to compress the rubber almost entirely.
The lead gasket would allow this compression without the 'movement' inherent in the rubber?
Normally my answer to those who like the rubber gasket would be the same as Raul's in other situations......"You probably like the colourations and distortions produced by this 'damping', but it doesn't make it right?"
However I respect Raul and the Professor too much to make light of their preferences so I will indeed conduct listening comparisons with and without the gasket as Timeltel suggests :-)
Dear Halcro: Mines are only " first " impressions and things could change over time to listening.

Yes, you have to tight the locking collar with " fierce ".

Btw, with the 20SS ( the others too but at differnt level. ) the O-ring makes the sound with more definition, everything is more clear ( not transparent ). It seems to me that with out O-ring " minute " distoretions there are higher and we can detect at frequency extremes where in the higher ones we could think that with out O-ring the sound is brigther and with more openess.

As I said we have " to play " more time around to be sure.

Regards and enjoy the music,
Raul.
Regards, Henry: Consider mechanically induced harmonics. These can be constructive or destructive. Raul's identification of a damping factor has the right "ring" to it, without the needed equipment for lab testing I think he's on to something. Boundary resonances are an influence not to be dismissed, cartridge isolation devices might also be productive in addressing this in a case by case manner. I've played with a few "home brew" applications to good effect in several instances. Years ago, Grado offered an aluminum plate with three raised dimples, essentially "tip-toes" for your cartridge. This was in the late '70's, there were many positive comments about it, and some negatives from the "purist" faction. Coloration, they said. The most sensible was to the effect that it did make a discernable difference, "use it if you like it".

Jcarr: always a treat to read your comments. An aquaintence of mine, a watchmaker by trade, recommends a pencil eraser for removing contaminates from soft metals. I'm sure you're already aware of this. The next time I visit my friend, I'll ask for a length of small dia. silver solder for a headshell join, thanks for the insight.

Peace,
Dear Jcarr: SAEC headshells comes with a non-rubber O-ring, instead the SAECs have a thin metal made O-ring that are fited to the headshell through a tiny screw.

It works?, well I never readed through the SAEC tonearms manuals I own nothing on the whys ( advantages or whatever. ) of that metal O-ring instead rubber one: yes it works but I can't say if better than with out it or than a rubber one, I will try to give me time to make some tests about.

Jonathan, your " thin sheet of lead " advise is the first time I " heard " about other than the SAEC metal one.
I would like that you could share with us your first hand experiences on the subject, it is really interesting.

In the other side you are just right, we have to take care ( deep care ) on those headshell and tonearms little " points " of contact where the cartridge signal must pass: as you point out these connections must be always in pristine condition.
I want to add that the cartridge own pin connectors must be always in pristine condition too so time to time it is good to make a clean " self " service alond the headshell own pin connectors and the headshell lead wires connectors at both extremes.

In many ways and IMHO this kind of clean task always pay high rewards.

Regards and enjoy the music,
Raul.
Dear friends: I forgot: the other headshell I owned with a non-rubber O-ring was the Victor LH-1000 that's a beautiful dark grey ( shiny top plate. ) 18grs ceramic one that comes with a metal O-ring this time rounded O-ring and not flat one like the SAECs one.

Btw, the " crazy " Japanese people are willing to pay over 1K for this vintage headshell, crazy!!!!

Regards and enjoy the music,
Raul.
Regards, Halcro (& Raul): Henry, you may find this interesting: "boundary resonance --- is of the same nature as a resonance in a system without damping: an increase is observed in the amplitudes of the characteristics of the wave --- unlike the conventional form of a resonance with finite amplitudes". Journal of Applied Mathematics and Mechanics, Volume 55, Issue 6, 1991.

Peace,
Dear Timeltel/all: As more listening time I take with this rubber O-ring inn as more makes sense that this " coupling " O-ring main target is to damp connection between two metal surfaces ( headshell and tonearm wand ) avoiding " boundary resonances " that at the end IMHO means : lower distortions.

Regards and enjoy the music,
Raul.
But here's the thing, Raul: The o-ring is made of a material that is dissimilar from the apposing metal surfaces. When the vibrational energy put into the headshell reaches the boundary between two dissimilar materials, a large fraction of it is reflected backwards, in this case back into the headshell. That might not be a good thing. This is why J Carr's suggestion of a metallic washer or ring seems better to me than rubber, altho the issue could be mitigated in the case of the headshell/tonearm interface, because there IS the underlying firm link between the two that constitutes also a partial metal to metal contact, which would permit some drainage of energy to the tonearm. As in all audio things, it's a trade-off, I think.
Regards, Raul: The most effective means of reducing boundary resonances were determined to be fibered materials arranged in non-parallel biases.

Perhaps OT but relevent to the subject of resonance, for an isolation platform I find merit in laminated bamboo supported by sorbothane pucks. The material fits the above description and is extremely rigid while remaining relatively acoustically inert. Most cabinetry shops will be able to provide and cut to size, constrained layer or mass loaded/spiked designs might also be given some consideration.

Anyway, back to MM carts. I'm finding much to appreciate with the Shure ML 140HE, might you find time to comment?

Peace,
Timeltel, But for whatever reason there are lots of audiophiles who despise the "sound" of sorbothane used as a footer or as a gasket. The usual indictment is "muddy". I have no opinion but have stayed away from sorbo for that reason. I have some very old big squooshy sorbothane feet that I have never used, in fact.