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

Showing 50 responses by lewm

Fleib, You may have been privy to my arguments with Raul re loading the Stanton 980LZS. I stated that my 980 did not open up and sound right at any load R lower than 1000 ohms. In fact, I use 1000 ohms with no added capacitance, and it still may need higher R or added C to optimize. Raul stated that he loaded the LZS at 100R, and others agreed with him. His opinion was, as usual, that I or my system, or both, were at fault, if I could not agree with his finding. In my system, the LZS sounds bloated and muddy at 100R. At 47K, it sounds not much different from 1000R, but I've tried nothing in between. What did you have in mind in making your statement?

Acman, Please expand on your statement. Are you saying that the male vs female connections of a B&O MMC1 are contrary to those of a standard P-mount?
If anyone still cares.... My re-tipped Grace Ruby at first sounded at least "good", with obviously more treble detail or a more pronounced treble compared to my other Grace Ruby, which is still using its OEM stylus assembly. So I expected it to get "really good" after break in. However, after about 20-30 hours, it was sounding "brittle", not to say irritating. There was a disconnect between mid-treble which was a tad edgy and lower frequencies, which sounded mechanical, to me. The OEM Ruby and the Acutex LPM320 clearly trounce the modified Ruby in that system. Well, really the modified Ruby sounds defective. (I know these descriptive terms can connote different things to different people; please use a grain of salt when interpreting.) I certainly do NOT mean to cast a slur on the work at SS, which receives so much praise from so many. In fairness to them, I need to discuss the situation with Peter L.

Yes, I played with VTF and VTA; nothing I did made much difference for better or worse.
The steering wheel alone of that 1946 Alfa is to die for. Thanks.
I have seen video of The Guild on TV at "Restoration Garage". They were restoring a particular car, not this one. The owner seemed like an interesting guy. Mine is a 1959 Giulietta Spider Veloce.
I dunno. Vintage Alfa's are more expensive in northern Europe than they are here in the USA. Some Dutch persons must like them.
p.178. I will look it up. My friend Dave Pogue still uses his, so far as I know. I don't mean to infer that the TL4S is a giant killer; it's just good enough to have caused me to question my core beliefs re MC vs MM, before I found this thread on Audiogon.
Re Storyboy's Complaint.
There are about a dozen guys who have been posting here for several years each. By now, I feel we form a "club" of sorts, where we can sit around in this ethereal meeting room and swap stories, ideas, opinions, even if the content strays from the dead seriousness with which the thread was founded. Thus I don't really care what Storyboy or anyone else thinks of the "status" of this thread, whether it is enlightening or not, dead or alive, boring or "pathetic". If one does not like it, one can either stay away entirely or offer up something new for discussion or information that is deemed to be "not pathetic". That said, Storyboy is welcome to hang out if he so desires.
Fleib, Please re-read my philosophical post. I say precisely what you say, Storyboy has a perfect right to hang out here as does anyone else. My point was that if he or anyone else finds the thread to be "pathetic", that person has the option of not hanging out here. After all, he was including your posts in his generalization. I am not sure that Storyboy equates off-topic posts with pathos, but I guess I am guilty of more off-topic posts than anyone else. So I will be the one to stay away until I have something of interest to contribute regarding MM cartridges. Meantime, I would love to find an Ortofon MC2000; if anyone….

By the way, Timel, my very first sports car was a 1967 Alfa Romeo Duetto Spider that I bought used while in med school. I drove it for 6 years in New York City, parking it only on the street in all weather and never in a garage. It was completely and utterly reliable every one of those days until I sold it.
Mapman, Magnets that are more powerful per unit of mass are always nice, but the upshot is usually more output, not necessarily better sound. Or in the case of MC cartridges, you can maintain a useable output whilst reducing the number of turns in the coil and thereby lowering the internal resistance and already very low inductance.
Fleib, You wrote, "Have you ever tried it with the sub arm not horizontal?" Yes, of course, that's what happens if you raise or lower the tower at the rear, which is easily done with the DV505 and one reason why I like the tonearm. I've tried it both ways, rear end up and rear end down. As mentioned, this did not do much to ameliorate the problem. The DV505 does have VTA "on the fly" (though I would never adjust it during play). The question is how to interpret the manual as regards the possibility that optimal VTA setting might result in a nonparallel relationship between the horizontal and vertical parts of the tonearm. Since the vertically pivoting part is so short from stylus to pivot, a very tiny change in arm height at the rear adjuster has a major effect on VTA. No, I have not swapped Ruby bodies and Ruby styli. Interesting idea. Do you have a math-based reason to believe that the OCL will sound better with some load resistance other than 100K, when the standard elliptical Ruby stylus does sound excellent at that R?
The issue with the OCL-modified Ruby is not so simple as to label it only "bright", a character that can indeed be tamed by adjusting VTA, in most cases. I would say there is more to it than that; but now it has been so long since I listened to it that I have to start over in my assessment. But most assuredly you are right that it is reasonable to play with all possible parameters of load and SRA.
Dover, Good point. The warning may simply relate to the possibility that the VTF will change if the vertical and horizontal parts of the arm are not plane parallel. That's no big deal to fix. In any case, I did ignore the warning and have tried changing VTA, which obviously requires one to violate the "rule" they put forth.
Audie, I always tried to remain calm when in a discussion with Raul, but you would have to admit, or you should admit, that it was Raul himself who was often the provocateur. To disagree with him is to admit that you must have an inferior system. To be using tube gear is to be someone who likes distortion. This is not to say that I do not find him interesting, informative, and even amusing at times. I would welcome his reappearance.
Nikola, Since you are a semanticist at heart, I know you will appreciate the fact that a "canon" (sic) is "a general law, rule, principle, or criterion by which something is judged" Whereas, a cannon will blow that stuff out of the water.
On the subject of VTF in particular and cartridges in general, you guys might want to read the summary of a talk given by Mitchell Cotter to the Boston Audio Society in 1977, when men were men.
Here.

You need to scroll down until you find the summary of his presentation. Cotter says for every cartridge there is one and only one "correct" VTF, the one that sets the VTA correctly. (I don't think SRA had entered into the lingo as of 1977.) He also says some interesting things about MC vs MM. For example, MCs are inherently more resistant to stylus drag, in the respect that stylus drag tends to pull the whole stylus/cantilever assembly forward from the cartridge body. As of 1977, most MCs were far superior to most MMs in resisting distortions caused by this effect, but there were some exceptions among MMs. And Cotter seems to have preferred MC cartridges to MM ones, but 1977 was still early in the battle.
Viva Raul! Did any of you guys receive a seasonal greeting from Raul via email? I did. Good to know he's OK. Happy New Year to all.
Dear Nandric, I think Acman has a point. He was not making jokes about Raul. To your point about the money Raul spent on cartridges. No one ever in history has done more to increase the cost of good vintage cartridges than Raul. When Raul amassed his collection, before starting this thread mostly, none of us were competing with him to buy them. So, whatever he paid, he got them much cheaper than did any of us who followed in his footsteps. Thus he actually increased the value of his own investment via this thread and our sheep-like behavior. This is all well and good, and no reason to be angry at Raul.

Further in defense of Raul, who can deny that Western Europeans (counting the American Caucasian establishment as immigrants from W Europe) committed many atrocities against African peoples over the last 3 centuries? As for Hispanics, there is some irony. Hispanics (if you include the Portuguese) have been on both ends of the spectrum, giving and receiving abuse. One can only hope for progress. If Raul is out of control mentally or emotionally, then he only has my sympathy. I would be sorry to hear that.
I liked the Ambrose Bierce metaphor, too. How many people know who he was and why he is important? Not many. But Ambrose Bierce disappeared into Mexico. Surely Raul has not disappeared into the USA.

Bierce would have skewered all of us for spending so much time and argument talking about phono cartridges.
Yep. I sent Peter a Grace Ruby with absolutely no cantilever at all, so in "re-tipping" he replaced suspension, cantilever, stylus.
Fleib, et al.
Some of these posts raise a question that has always lurked in the back of my mind: Do "specs" on a phono cartridge tell us anything about how one cartridge sounds compared to another? For many reasons, I have always assumed the answer is "no". The specs can tell us what voltage output to expect, roughly, and how to load the cartridge, but otherwise I never even think about comparing the published frequency response, channel separation, and distortion figures, to choose one cartridge vs another. The foremost reason for that is related to what Fleib pointed out; no two cartridges sound exactly alike, even if they are the same brand and model.
Dear Nandric, Is it possible for you to weigh your heaviest Orsonic and let me/us know the result? I would be curious to know how it compares to my two AV101s. Let us know whether you weight with vs without the detachable yoke to which the cartridge is fastened. Thx.

Dear Fleib, i did concede that cartridge specs, most notably inductance and internal resistance are valuable for knowing how to load the cartridge properly, particularly as regards high inductance MMs. (I guess I did not say that last part in my earlier post.) But for pure sound quality (whatever that is), I never have paid much attention to stated frequency response, distortion, and channel separation specs (back in the day when such data were supplied with each cartridge). Whereas, Raul seemed to place a higher importance on such numbers.
Dover (and possibly others), is the MFG61 unusual in that it has a low compliance? Otherwise I have to wonder whether your impressions of its sound are "colored" by the fact that it is mismatched with the FR64S. I know Raul convinced many that the "rule" about matching compliance and effective mass is made to be broken, but I have to think there are some limits to the heresy he championed. Since all these judgements are subjective, it is nigh impossible to know where the limits apply, however.
Could be wrong, but I did not think eff mass of FR64S was quite THAT high (35gm). I assumed it was in the 20-30gm range. Some of those data on VE are suspect, at best. Of course, one variable is the choice of headshell. I think the FR headshells can be quite heavy. So, maybe with the heaviest FR headshell, the eff mass of the FR64S could exceed 30gm. And if so, one can only imagine what is the eff mass of the FR66S, which some here have used with MMs. (I own an FR64S, but like Dover, I use it with a light-ish headshell. Only so far with a Koetsu.)
I've been using an Acutex LPM320STRIII (heretofore to be known only as "LPM320") for quite some time now on my Lenco with Dynavector DV505 tonearm. The Acutex alternates with a still original Grace Ruby. At first, the Grace had the edge, but lately, after putting many more hours on the LPM320, which was NOS when I first mounted it, it has really blossomed. It now competes with the Ruby, but that I think is in part due to the fact that the Ruby is heading for a new stylus. (I also have that other Grace Ruby with the new SS OCL stylus that sounds BAD; I need to send it back to SS.) Has anyone tried the rocket-ship mount on the Acutex LPM series? Raul declared it was a downgrade from the P-mount, but I have to try it some day, just because it's so cool looking. I've got an M320 too, just sitting.

My 980LZS, also purchased "used", seems to be deteriorating a bit, but I've got an NOS 981LZS to replace it. The old-timer 980 got whupped by an Ortofon MC2000 (ex one of our colleagues here) riding in my L07D. What a quaint old collector type I have become!
Well, there are numerous tube preamps with insufficient gain for MC (the ones that require or suggest using a SUT with an MC). Any of these might be more or less suited for MM when used without a SUT (meaning that they might be especially good sounding with MM, or not). I just wonder whether anyone has made such an observation. On the solid state side, there are the Graham Slee phono preamps that do appear well suited for use with MMs, have some adjustability, and don't cost an arm and a leg. There are probably many others that I don't know about. Raul, thank you for the added info in the longer of your two posts above. I knew the B&Os were MI, but I did not know about any of the others you listed. I am also curious about the upper level MIs made now brand new by Soundsmith. Altho you have commented on their B&O-like efforts, I think Soundsmith would claim that these are not the products by which they would want to be judged.

In terms of moving mass, MM types and MI types lie on both sides of MC types (MM much higher, MI much lower), so it does not seem likely that moving mass per se has anything to do with why you guys are finding so much delight in these old products. Perhaps it is just the robust voltage output, which makes life so much easier for the phono preamp, that is the root cause.

I intend to give these cartridges a try, as soon as I can find one to buy. And I am in the market for a reasonably priced MM- or MI-only preamp. I have to say that I go back a long time in this hobby, to the days of MM cartridge dominance. I owned my share of Shure V15s (Type II, I think), Stantons, Deccas (SC4E, London, the one with the conical stylus that HP used to adore), and ADCs (XLM, to be specific). If my sonic memory serves, the best of them all was the Grado TLZ, whereas I really did not like any of the other Grados. (The TLZ was much faster than any of them.) I also have fond memories of the ADC and good moments with various Deccas, but I really never did like the Shures very much and felt they could not compare to most of the rest. I always had a vague feeling that something was lost with the advent of MC cartridges, now you guys are making me think I might have been right.
Dgob, I don't think any real world LP can reproduce a 15Hz signal, more like 30Hz is the lower limit, excepting specially made LPs that may exist.

Regarding the Nagaoka MP50. Both the MP50 (not the Super version espoused by Raul) and the MP500 can still be purchased new. One source is William Thakker on eBay. (Goatweiss asked about this.) If you look at the specs of the MP50 vs the MP500 they are completely identical in every aspect. Only the color scheme of the two cartridges differentiates one from the other. Yet, the MP500 costs $150 more than the MP50. Perhaps this is due to differences in construction of the body to dampen resonances, etc. Or perhaps there is no difference except $. Anyway, that's just my observation.

In the past several weeks I have been able to pick up a B&O MMC20CL and MMC1 (NOS), and an AKG PSE8. Plus I have my old Grado TLZ, which I used to like quite a lot and which Win Tinnon thinks is a winner too. I will be comparing them in about a month after I get my MM amplification up and running. I will restrain myself from buying a Nagaoka unless or until I find faults with what I have got.
Dear Raul,
Please stop making me spend money. I will soon be living on bread and water, but I will have a lot of turntables (5), tonearms (>5), and cartridges (probably about 9 total of all types right now). I actually have recently sold 3 turntables, so I am feeling righteous with "only" 5.

I realize that since I have thus far auditioned only the Grado and the Ortofon M20FL among my non-MC cartridges, I have yet to listen to a true MM type. The Grado calls itself an "induced magnet" type and the Orto is a Moving Iron type. I also have two B&Os, which are both MI. I guess the Andante P76 and the AT20SS are both MM. The Nagaoka MP50 is calling me.....
I have to say that I so enjoy the Ortofon M20FL Super that I still have not auditioned any of the other MM/MI cartridges I collected before starting to listen to them. This includes an NOS B&O MMC1. Of course, I did start with the Grado TLZ, The Orto is superior in most ways, but my Grado is more than 20 years old and could be suffering from stiff suspension (actually, a blessing at my age). Further, I mentioned previously that I discovered that I had been auditioning the Grado with its stylus assembly slightly askew in the cartridge body, so the Grado may be capable of more than I know, because it is sitting there unused. I guess I am obliged to continue the process, even though I could happily stop where I am with the Ortofon. I confess I bought a second one from Thakker. Meantime, where is the Andante P76 in all this? Has it faded from its once lofty position?

Raul, I have an AKG P8ES with a sagging cantilever. Do you think vdH could repair that while preserving the special qualities of the S? How did you/do you like your uber version of the AKG? (Can't recall the model name.) You told us you got one but I don't recall reading that you had listened to it.
Dear Henry, Who knows? RFI is a strange phenomenon. As long as you are rid of it, that is the important thing. I have a feeling that the Copperhead tonearm is really the best product out of Continuum, or at least it's the only one I have any hope of ever owning.

Dear Raul, I was just "pulling your leg". I know you would not post an opinion if you did not feel you had done the work that backs it up. I do think you changed your tune radically as regards the M20FL, OR you were just being polite in the first instance, to go along with the accolades that I and others gave it. But your opinion is your opinion. I will have to find out for myself in my system what I like best. In fact, it would be great if the B&O MMC1 or the Andante P76 (two on your list that I own) were to be superior to the M20FL Super, since I like the latter cartridge so much already.
Dave, I paid $500 for my NOS B&O MMC1 several months ago. I am glad to know that my investment now makes sense.

Re the MP50 vs M20FL comparison, I have no basis for confirming or disputing your conclusion, but if we scroll back up the thread a bit, I think someone else posted a contrary conclusion not too long ago. How about P77i vs MP50? If I have another $500 to blow away, which one would you suggest and why?
Dear Raul, I guess my last question to you did sound like I was agitated. I just wanted to be absolutely clear on what it is that you are according such rave reviews, here and elsewhere on the internet. I foolishly sat still while others gobbled up those NOS Technics cartridges, but at least now I can have some hope that if I find a good used one, it can be revived to the level of yours by vdH service. But I also have so much other vinylphile work ahead of me that I should be able to wait for the ECP P100C, in whatever form. I have yet to "taste" the Andante P76, the AT20SS, the AKG P8ES, and the B&O MMC1 and MM20CL., for examples. And I am about to set up my Kenwood L07D turntable, now that it has been completely serviced, tweaked in a few ways, and calibrated. Everything moves slower for me than for you, because I have so many other obligations and distractions. I have you to thank for this adventure. This is the essence of a "hobby".

Dear Timeltel, I never even thought of doing the trigonometry to actually calculate how many degrees of VTA I am using. Very clever, yet obvious. It's a bit more difficult for me, because I am using the Dynavector DV505, where the vertically pivoted arm is so short, and the horizontal part of the arm is always level. I was just guessing at the angle by eye, as I said.
Funflyer. Thanks for your input. I agree with you that the thread has become a little too focused on minutiae, and perhaps I am a major culprit in that trend. Please know that I am totally aware of it. To some degree, I went ahead with my posts to keep the thread alive, because Raul seemed to go off on a tangent in his preoccupation with the Technics EPC100C, for which he started an entirely new thread, in fact. This is Raul's perfect right, but the rest of us were deprived of his weekly or monthly "discoveries", which were previously the life's blood of the thread. In fact, thanks to Raul, we have a huge backlog of cartridges to talk about in greater detail, not just the Azden P50VL. I wonder what happened to the AT20SS, the Astatic, the Grado Tribute, the B&Os, the AKG P8ES, etc? How do they compare to the Empire/Azden/Ortofon cartridges of more recent interest? The thread could go on forever with that much fodder. So if my recent posts were of little to no general interest, I apologize. But don't go away. Stay with us.
I personally am still wrestling with the question of whether the best of these MM/MI cartridges are indeed competitive with the best of the MCs. Too bad that it is very expensive to buy exotic MCs with which to make comparisons.
Dear Raul,
Here it is:

http://www.vinylengine.com/twisting-your-cartridge-headshell.shtml

I think instead of using the term "tracing distortion" as Seb does, the better term is "tracing error", because we don't know that these angles translate into distortion in any linear way.
Addendum on Acutex. I did a web search this morning. I am getting the impression that there must be two genera of Acutex's, one of which is P-mount and the other of which uses the standard 1/2-inch mount. The styli depicted here, at BluzBroz, look as though they would fit my 1/2-inch type cartridge body.
http://www.adelcom.net/AcutexStylus1.htm

The M312STR stylus assembly I bought at Turntableneedles (shown at the URL below) is in retrospect intended for use only on the P-mount versions of these cartridges.
http://www.turntableneedles.com/Acutex-M312-Stylus_p_3845.html

Can anyone confirm that my hypothesis is correct? I would appreciate it.
Where are the early B&O cartridges in all of this? I refer to the MMC1, MMC2, MMC20CL? I own two of these 3 and have not even taken them out of the box yet. Has anyone been listening to any of them? There are just not enough hours available to me to do these things justice.

Raul, thanks for your response re the AT20SS.
Hey, DU. I can safely say that I seem to have lost the bug to buy ever more vintage cartridges, now that I own nearly 10 that I have not heard at all, not to mention the 4 or 5 that I have been listening to. The unheard cartridges include a few Acutex's, Empire 1000ZE/X and D4000/III, AT20SS, AKE P8ES and P8Evandenhul, B&O MMC1 and MC20CL, Pickering XSV3000, and Stanton 881 MkII. Not a bad lineup and one that makes me feel as if I have eaten a full 7 course dinner already. Meantime, I have a broken monoblock amplifier that so far has resisted all my thoughts on what could be wrong with it. And I cannot entrust it to anyone else, since I built it from an Atma-sphere kit about 10 years ago and have since modified it so many times that Ralph would barely recognize it. Thus my system has been out of commission for nearly 6 weeks. (I don't get too much time to work on the amp.) Plus severe illness in my family puts it all way on the back burner.
Timeltel, Thanks for that interesting reference. If memory serves, MC cartridges with very low internal resistance (e.g., <10 ohms) typically also have a very low inductance, in the micro-Henry range (as you might expect given the low number of turns on the coil), as opposed to the mH values given in that thread for MM cartridges. Thus it is not surprising that the optimal loading of the two types of cartridge is also about 1000X different and proportional to inductance.
Dear Raul,
I know I am beating a dead horse, but it is one thing to list the cartridges you think are worth auditioning and another thing to cite the eBay auctions. Anyway, I don't really care very much, because my own appetite for vintage MM and MI cartridges is completely sated. I will never wear out all the cartridges I now own, some of them thanks to you. I was just feeling empathetic with the plight of Nandric and some others who are trying now, in some cases with limited funds, to acquire some of the cartridges that have become scarce and expensive, largely because of this thread. Carry on, as I know you will.

To all, A while ago I brought up the question of B&O cartridges. These are all MI types. Raul spoke highly of several of them, including the MMC1, MMC2, and MMC20CL, very early in this thread, maybe in his original long post. However, there has been no mention of any of them in more than a year. I am wondering whether anyone else has acquired a listening experience with any of these, in comparison to some of the others that have recently been under discussion. Back in the day, I thought they were "hi-fi-ish" sounding, but that was in the B&O straight-line tonearm and typically in a B&O showroom using their gear downstream.
Raul, You are a piece of work. Thank you for raising the value of my NOS B&O MMC1. I probably should not use it at all, because that would lower the value. I think I paid $600 for mine; that was the most money I spent on any of these MM/MI examples. My reason for bringing it up was simply to generate discussion; thanks for the discussion. I was getting a little bored with the Signet stylus discussion that came before. Also, since I have many cartridges here that I have not heard yet, your and any one else's opinions help me to decide what to listen to next. I don't like fiddling with cartridge installation, so it is my inclination to listen to what is installed in the system on any given evening, and I only get one or two hours a day to listen to music. All of these are reasons why I asked about the B&Os.

By the way, I posted before you did on the need for a special adapter for the B&O, so if anyone is considering buying the one on eBay, they should take into account the extra $50 that SoundSmith will charge for a custom adapter. Peter Lederman does not much like making them, either, so you may have to wait.
I don't pretend to have a lot of technical expertise about how cartridges work, except on a basic level. But here is a quote from M Fremer, from his review of a SoundSmith cartridge:

"Moving-iron designs such as the SMMC1, or the Grados, use stationary coils and magnets and a small piece of "moving iron." In the original B&O design, what moves is a cross-shaped piece of ultra-low-mass, high-purity iron attached to a soft elastomer damper stabilized in a plastic frame. The iron also incorporates a minuscule tube into which the cantilever is inserted. Each arm of the iron cross is associated with a fixed-coil/magnet structure and as the cantilever moves, it varies the distances between the four arms of the iron cross and the four fixed-coil/magnets, thus inducing tiny voltages within the coils. The advantages of this arrangement include ultra-low moving mass, even compared to an MC design; relatively high output (because the stationary magnet/coil structure can be made large); high suspension compliance; and low vertical tracking force (VTF)."

Note the comment about moving mass relative to an MC cartridge. I am sure DT made an innocent error (I do it all the time), and indeed for all I know it is possible that for some MCs and some MIs, he is correct; a given MC cartridge could have a lower moving mass than a given MI cartridge. But it does stand to reason that because the cantilever of an MI cartridge need not be burdened with either a coil of wire or a magnet, the moving mass would on average be lower than for either of the two other types..
Dear Raul,
Depends on how you define "LO", does it not? LO for an MM could be anywhere from around 1.0 mV at 5cm/sec down to 0.15 mV. That's a ~10-fold range. So if we have a reasonable output of say 0.6mV, that's only about a 7 to 8 fold different from a typical MM at 4.0mV or so, which I hope you would call "high output". That difference in output does not require anywhere near to 40db extra gain from the preamp, more like <10 db extra should do it. (I have not stopped to make the calculation and cannot remember the log of 8.) OK, so why do it at all? My answer: wouldn't such a cartridge have lower inductance than a 4mV MM, which by the accounts of Timel and Dlaloum would be advantageous? Then if you also eliminate flimsy junctions between stylus and body, use an exotic cantilever and a state of the art stylus shape, you might really have something. Just a thought.
Assuming that the P-mount itself is of decent quality, e.g., the one that comes with the Azden or with the B&O cartridges, you can just solder the tonearm wires directly to the P mount pins, and then use the P mount in the conventional manner. Same result: the elimination of one set of connectors in the pathway. This is what I did with the Azden. But I never fell in love with that cartridge, as many of you apparently did.

And if one is really obsessive about connectors, what about those additional connectors at the rear of the typical removable headshell? If you use a Pmount with a removable headshell, you typically have connectors: (1) cartridge body to Pmount, (2)Pmount to headshell wires, (3)headshell wires to rear of headshell, (4)rear of headshell to contacts at end of the tonearm wand, not to mention (5)DIN plug if you use removable tonearm ICs, and (6) RCA jacks. It's a real wonder that any decent sound gets through all that crap.
my only question was "what is the effect of shape of a solid homogeneous piece of any material on its resonant character?" The key word is "homogeneous"; I am not talking about CLD. The material could be acrylic, bronze, brass, stainless steel, slate, Panzerholz, etc., altho the latter two are "natural" and are actually not homogeneous in terms of grain structure. So perhaps they are not to be considered. Just shape vs resonance.
Don, did you have to go and spoil my recipe? The MF100 was fading from memory slowly. I was preparing my attack carefully. But NOOOOOO; you had to throw salt on my ice cream, water in my coffee, basil on my soufflé.

Truthfully, I am stuffed. Could not digest another cartridge if my life depended on it. On the other hand, I thought I over-stepped when I purchased the Grace Ruby, did not need it, had too many already, was getting ready to re-sell it without an audition, and even at a loss. But then I fell in love... I suppose the same thing could happen all over again with the MF100/200.
Thanks, Ecir. I know how to calculate the values, and I have already decided to use an ELMA 12-pole stereo switch that I bought from M Percy and which I know will fit nicely at the rear of my MM phono stage. My question was really about what values to shoot for that will optimize the majority of these MM and MI cartridges. (Your workmanship is admirable by the way. Nice job.)

My favorites among them are the Grace Ruby and the Acutex so far (Ruby over Acutex, but maybe the loading will change that opinion). (Don't laugh; I STILL have many more cartridges to audition that have been sitting around here for a year or more; when I like something I tend to want to stick with it rather than rush to find out what else I will like.) I plan to be listening to the AKG P8E and P8E vdH, or whatever it's called; I have both. Also, the B&O MMC1 and MMC20CL(?) And I've got Stanton 881S, Pickering XVS 4500 and etc. My other established favorite, the Stanton 980LZS is running into my MC phono stage, the built-in section of an Atma-sphere MP1, loaded at 1000R. I want to buy an MC that can challenge these babies, but I don't know what that would be.

I tend to side with Raul; if the cartridge is capable of an extended frequency response, why knowingly attenuate it unless the extended response is per se a resonant peak? Can't that peak be tamed with capacitance, Timel?
Anyway, I feel licensed to start with just adding various amounts of C to 100K for R. The Grace in my system sounds wonderful with 100K load and no added C, but I am not certain how much C is being delivered by phono cable and the Miller capacitance of the input tube and etc.
Gosh thanks. I SAID that perhaps Panzerholz AND slate should not be included on my list, because they have grain structure or are not homogeneous. Bronze and brass (and stainless steel) are indeed alloys, but I think alloys DO qualify for this analysis. (Last time I cut into a piece of brass, I did not notice any obvious inhomogeneity.) Acrylic can be considered in the category of an alloy, for this purpose. OK?

Here's a way to phrase my question: "What is the difference in resonant properties between a sphere made of one pound of acrylic vs a cube made of one pound of acrylic?" I could imagine that they could be different, but I wondered whether there are established rules that describe the differences. Timel, does "Young's Modulus" address such issues? (On now to Wikipedia.)

Or would you prefer only elemental materials that appear in the Periodic Table? OK. Iron, nickel, yadayada.
Audpulse, Thanks for reminding me it was Roger Modjeski who made negative comments about some brand of boutique audiophile fuse. Like you, I am not sure whether to take his word for it or not. But on the other hand, he was not rendering an "opinion". He claimed to be reporting on a direct observation after having dissected one of the fuses.

So, Raul and Frogman, just to take the Devil's advocate position, the difference between all those tweaks that you listed and the tweak of a fuse in the AC line is that all the former ones are in the signal path, whereas a fuse in the AC line is "behind" the entire power supply with respect to the entire signal path. (Mind you, I have no opinion of the effect of fuses on the AC side; my observation is that a quality fuse in the signal path of my amplifiers does certainly make a difference.) So if you hear a difference with a silver/cryo/ceramic fuse on the AC line, tell me this: have you tried to hear a difference based on the "direction" of the fuse? As you may know, real "tweakers" claim that fuses have polarity. This idea makes zero electrical sense to me.

One possible effect of a fuse on the AC line could be via its electrical resistance to current flow. If a fuse has significant resistance, it could conceivably rob dynamics. But I have never detected DC resistance in even the cheapest fuse, when measured with my meter in open air. Nevertheless, we could posit that silver fuses have lower AC resistance than conventional ones, when operating below the current limit. It actually makes some sense. But this is easy to measure and I wonder why no one has brought this simple fact to light, if true.
Dear Raul, I've got Pickering XVS4500 and 7500. In the latter case, it may be that I have just an NOS XVS7500 stylus, which I purchased as a future replacement for the unobtainable D98S Stanton stylus in my 980LZS. You might also try your XVS4500 stylus in the LZS version of the Stanton. (I assume you have one, since you have such a strong opinion of it.) Also, have you tried the all-Pickering version of the XVS5000? One could do just fine with only Stanton and/or Pickering products of yesteryear. Great stuff.

Don or anyone, where does the XVS5000 fit in the scheme of the 4500 and 7500 cartridges? Was it a special model specifically for 4-channel LPs? I guess I can look that up somewhere.

I tend to agree with your generalization about tracking ability as a correlate of performance excellence, but then why is it that the MC has reigned supreme for so long, and remains supreme among most? Pavlovian conditioning of the buying public, perhaps?

I long ago spotted the Victor tonearms as stone cold bargains in today's market, but I've never bought one, because I don't "need" it. The quality of construction is obviously top level.
My dear Dover, The most fun about your posts when they follow mine is that I sometimes cannot figure out whether I am being insulted, or not. In any case, "euphonic hyperclarity" could be seen as an oxymoron and certainly did not attract me to the Grace 714, since I have never heard a Grace 714 in action in my or anyone else's system. (Is that now hyperclear to you?) As to the rest of what you wrote, was that sarcasm? If not, I apologize. I gather you are not a fan of the Grace 714. Cool. You may be correct in that opinion, so far as I know. Based on internet comments, some do seem to like it.
Does anyone recall some earlier Clearaudio turntable designs, where the plinth was made of solid acrylic cast in a "curly" shape, something like that of the top of a baby grand piano? They said it was to control resonance, but I was dubious, because in the first place if you use solid acrylic, it's going to resonate at the frequency of that particular mass of acrylic, no matter what the shape, or so my off the cuff thinking told me. I then searched the internet to find out how and if the shape of a solid object, independent of its mass, of homogeneous material content could affect resonance. I really never found a good treatment of that subject.

At any rate, I notice that the most recent Clearaudio turntables use layers of several different materials to effect CLD, but nothing exotic about their shape.
Dear Raul, That is very interesting, what you say about Guillermo's motivation when he purchased the Sound Labs. I still stand ready to give him some tips on important upgrades that will dramatically improve them. The first, easiest, and cost-free thing he should do is to disconnect/bypass/discard that "Brilliance" control. It is a cheap L-pad that adds a gray coloration to the sound, and since the treble transformer operates at frequencies from about 250Hz (where it is 6db down) to 20kHz and beyond, removing it is like going to the dentist to extract a nagging tooth that is aching; after you've done it, you wonder why you ever put up with it. Better to control the tonal balance by room treatment.