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.
rauliruegas
Dear Dover, I have no problem at all to admit that I was
wrong. Anyway if math. is involved I usualy skip the whole
subject matter. And I just started to like you. How about
'Fourier analysis' as a separate-separate thread?

Regards,
Well then the answer to Lewm's question is yes - shape will affect resonance.
You can mathematically model a proposed shape using fourier analysis, but the traditional method of measuring resonance is the use of accelerometers to measure the resonances induced by applying a frequency sweep to the item to be measured at multiple points. The pencil & ear test does not really do much here as I would surmise that it is checking the dampening behaviour at 1 frequency point only for the particular mass, size and shape of both the pencil and the sample material tested. The "sound" of the tap will vary with the positioning of the "tap" on an irregular structure as well. Of course if you add feet - 3 or 4 - then you have built a trampoline and the resonances induced will be quite different to no feet, or varying the location of the feet.
The more complex the shape the more nodes there will be that need to be factored into the calculations. A concave plinth will have more nodes and the maths will be more complex than a flat plinth for example.
Dear Dover,It is an old tradition to try to nail subject matters with categories or classifications. Those however are verbal and belong as such to language. The other part
is called 'reference' while the aim is to point to the so called 'reality'. We need both to discovere the truth. Well the reality is that among others our Lew is unbelievable eloquent and even more inquisitive. Why should he split his curiosity in different threads? I enjoy reading his post and prefer the same place or thread to find them. I am sure some other members will agree with me but, of course, not everyone. Those however can chose among many other threads to satisfy their 'categorical needs'.

Regards,
Hi Don, LOL the one I didn't like came from TTNeedles. The good one came from LpGear. I suspect they were from the same mfg. They looked identical. I doubt if Jico makes them exclusively for others, while they don't sell them themselves. Who knows?

If you check the bottom of the cart of the 120/440 series, against the 3400 (95, CA) series, you'll see that the cantilever angle is a little different. If you have 2 respective plugs with stylus and compare them, it's easy to see. An alum cantilever can be bent down slightly to work in the 95 plug, but beryllium and boron tend to break. Isn't the 152LP beryllium? If so, I hope you have better luck than I had. Maybe I'm just getting too old, but I broke a beryllium and a boron trying to transplant from a 120 series to a 95 plug. One of them was an irreplaceable 152MLP. Such is life.
Regards,
Mainly for Raul, My friend....I propose that you need to do ABA type of evaluation for those fuses or any other audio comparison.... along with putting some time in between like live with it for a month then go back to your original fuses or what have you... and redo your evaluation...also your music selection is bogus thats a studio recording! WTF?!

Raul my friend you seem to want to get to audio nirvana (like live music) but you have done no comparo testing as in ABA

I will say that i am sure i am much younger then you and have a better audio memory and hearing or at least we maybe on the same level but my point is... irrational quick decision making is non productive...maybe if you like to play with your audio components and get yourself off....... but IMO you will never get anywhere.....

my reasons for saying this is depending on the time of year time of day your mood etc....you need to average it out in a much longer evaluation

now i Know there is no absolutes in audio but personally if I am going to spend time and read your postings please write something worth reading...IMO your getting audio goofy on me...

and for Christ sakes get some good non molested live music for your comparisons patrica barber?! Really!!!

Lawrence
Musical Arts
Lewm - you should probably start with another thread on plinth shape.
If you are embarking on a new plinth you should really start with a comprehensive project definition listing your requirements. What are you trying to achieve, what are the deliverables.
For example the plinth requirement for a vintage idler, which has more shake rattle and roll than Elvis' hips, in my mind would be vastly different than for say a Direct Drive turntable, most of which the motors are mounted in a resonant pudding bowl. The resonances generated by each drive system would be quite different.
Do you want a dead plinth ?
Do you want a plinth that deals with the vibration & resonance of your particular TT motor drive ?
These could yield radically different results depending on your goals.
What arm and cartridge are you going to use ?
What are their resonant characteristics and grounding requirements ?
Does the intended tonearm use dampening or does it require energy to to dealt with by the plinth ?
What are you going to place your TT on ? Wall shelf ? Stand ? What type of stand ? What materials ?
Even if we assume Richards solution is nigh on perfect, the resultant structure will still have fundamental resonances and at some point at least one will be increased in amplitude relative to the initial impact.
But what would your fundamental resonant peak requirement be ? Assuming it is in the musical bandwidth - then where ? What is going to do the least damage to the music ?
Most of the plinths built are tone controls, a cacophany of complementary colorations that 'sounds better because I spent so many months & $ building it' it IS better. Did you strip off the wood from the slate to check what had been traded off for the gains you heard ?
As I said above start by writing down a list of your requirements, then let's debate that, before we start on materials & shape.
You might like to engage your local university or technical college, where with Fourier Analysis software quite commonly available you might find a student interested in taking up your question and doing some modelling for you. Ideally they may have measuring gear that can determine the resonances inherent in the TT drive system to start with.


Lew, while I can't offer any commentary re how the shape of a material might affect it's sound (resonance characteristics) in a turntable plinth application, I can tell you that the shape of the material is an important consideration for musical instrument makers. I see no reason why some of the same principles would not apply. I am not talking about the shape of, for instance, the bore of wind instruments or the shape of the resonating cavity of string instruments. In those examples we have a case of a vibrating column of air and it is much easier to understand (and is well documented) how altering the shape of the cavity created by same materials of the same mass would affect it's resonance.

Take the case of a clarinet barrel. The clarinet barrel is the small piece of tubing that is found between the mouthpiece and the upper of the two main, and larger, parts of the clarinet. It is a kind of interface between the mouthpiece and the main body of the instrument and is most directly affected by the reed's vibrations. There are two design parameters that have the most profound effect on the response/sound of the barrel, the shape of the bore and the shape of the barrel itself. The impact of these two parameters in design choice are at least as significant as the choice of material. You can have a barrel that looks like this:

http://backunmusical.com/product/fatboy-barrels/

which has the exact bore taper and dimensions, and uses the exact amount of material as one that looks like this:

http://backunmusical.com/product/moba-barrels/

and they will each have entirely different response characteristics and sound. Barrels are typically constructed of various types of wood such as cocobolo, rosewood or grenadilla, hard rubber, plastic, or metal. It is surprising how small the differences in sound are between the different materials compared to the differences due to the shape used.

I think that it is entirely plausible that the shape of a piece of metal or acrylic (homogenous) would have a significant effect on the way that it resonates due to externally (ambient) and internally (motor) caused vibrations in a plinth application.
Dear Richard, Your research in the area of plinth design and construction dwarfs my own very limited experiences. It seems that I am doomed to be misunderstood here; I meant no slur on acrylic in my previous post. I only meant to say that it is not acrylic per se that I wonder about but merely what is the effect of shape, assuming a plinth made of any homogeneous material. Since acrylic lends itself to shaping perhaps better than most other commonly used materials (wood, slate, lead, granite, etc), and since Clearaudio in fact used acrylic, the discussion happens to center on the use of acrylic.

As to your other experience, I often wonder whether tapping on the plinth tells us anything at all about its goodness as a plinth. But I have very firmly come to think, like you, that combining two or more materials in layers, so as to affect CLD, is the way to go. I was very happy with my all-slate plinths for a long time until I had a carpenter make me a baltic birch and cherry base for my Mk3 slate plinth. I then affixed the wood base firmly to the bottom of the slate, using 5 or 6 large diameter bolts threaded into inserts that I epoxy'd into the bottom of the slate, after drilling holes for the inserts. I then bolted the Mk3 chassis thru both layers, using very long metric screws (the total plinth is now nearly 6 inches thick). The result is a huge improvement vs slate alone, in terms of total "neutrality" (the holy grail). (Using also Albert's idea of the bolt that engages the bottom of the bearing housing so to transmit vibrational energy to a large brass block mounted below the chassis. Albert uses brass bolt/iron block. I use brass with brass.)

As to what materials sound good, I only know that MDF sucks.
Hi Fleib,
Your comments are one of the underlying reasons I bought mine from TurntableNeedles.com. Their add states Jico manufactured. Actually never had a problem with either suppliers but truth in advertising being what it is, well, stated Jico, I went with them. I had taken notes from some of your statements pertaining to this transplant and did have on my list a ATN7V. Now that I have done this opperation, I just might do a 152LP that I have lying around next. Maybe my 440MLa (also not being used). This just might be fun. You are one of the people I must thank for leading the way in this transplant. Thank You!
Regards,
Don
Regards Griffithds, I was reading a thread on Karma and someone asked LpGear/tunes if their Vivid line replacement stylus was made by Jico. Their reply was, it is not. These ATN95 styli also do not appear on Jico's site. There was some conjecture about the identity of the maker(s), but no conclusion.
Of the available styli suitable for replacement or transplant, the ATN7V is quite good. Cu is nearly identical and nude .2 x .7 elliptical performs well, good detail if not as sweet as the shibata. Quality control on the replacements isn't perfect. Of the 2 examples of shibata I bought, one was better. I suspect you got a good one.
Regards,
Lewm . My two cents worth. I have been building TTs for over 30 years now. Some have been disastrous and some ok and only a few were good
Plinth materials have been. Slate, concrete, aluminum, MDF, hardboard and finally acrylic using lead in a CLD laminate. Both acrylic and lead get bad press. This is in my view not justified provided they are applied correctly.
If you bond acrylic to lead with a hard exoxy glue the resultant laminate has most interesting properties.
One test I conducted during my research into plinth materials was to tap the plinth with a pencil and listen to the plate with a stethoscope.
All of the materials were glued to lead and then subject to this test.
The concrete slate and aluminum still rang slightly. The MDF and Hardboard gave a slurred sound indicating a smearing effect. The acrylic gave a short, sharp and loud tic. It took me some time to appreciate what this meant. The conclusion is that there is minimal storage of energy " short, sharp" and that it conducts this energy quickly " loud tic"
The trick is to glue with a hard epoxy. I adjusted the Hardner ratio to get a material that was the same hardness as acrylic. In this way the acrylic is effectively fused to the lead. Lossy, soft glues were disastrous.
Listening tests were conducted in a search for the material that gave the maximum difference between LPs. Since each LP sounds different, by definition, greater audibility of these differences implies less coloration of the TT itself. The second and probably most important test was to listen for a connection to the music. Did I connect with the musicians, how did it make me feel. Again Acrylic lead scored the highest by these two metrics

I have not tried panzerholst but can report that Albert Porter gets excellent results with his highly engineered plinths.

Regarding material shape, I have no scientific input on that interesting question. The triangular shape chosen was to facilitate the three feet whilst almost eliminating any part of the plinth from being cantilevered outside of these feet. This approach seemed to be logical. That said it may be wrong regarding resonance control. I also find it pleasing on the eye. An agreeable byproduct.
Regards, In_Shore: I've a JVC TT-71 deck on the back burner, have been giving consideration to matching it up with a MS-505(S) TA which gets good ratings from several trustworthy A'goners. Also have a spare EPA-B500 (base) with choice of either the curved 250 or straight 500H wands.

Should you have Panzerholst remnants available this spring, please give me a reminder.

The Pioneer PL-70L-11 http://audio-database.com/PIONEER-EXCLUSIVE/player/pl-70lii-e.html is in excellent condition. Have both straight & curved pipes, a treat to both eye & ear.

Best wishes for the new year &

Peace,
How about we start the New Year off with a horror story with a happy ending!
Of the 2 Virtuoso's that I own, the Black with the Sound Smith's cantilever/stylus is the one kept in rotation. The original Red Wood with factory stylus/cantilever has been occupying shelf storage space. I discovered early on that its stylus guard also fits the Signet TK10 MKII cartridge in which I bought guard less. The TK10 also is kept in rotation so I have been storing the Red Wood guard less. Well a couple of months ago, while fumbling around looking for something on the shelf (wearing a sweater), somehow the bare stylus caught on my sweater sleeve and was flung across the room, bouncing off the far wall. After staring in disbelief, the only word that came to mind was S**T. I should of ordered a spare guard.
Well, a few weeks ago, when my wife asked me what I wanted for Christmas, my quick reply was a Jico/Shibata stylus. After explaining to her what the hell I was talking about, one got ordered.
To make this long story somewhat shorter, it has been received and the necessary trimming of the stylus housing has been accomplished and said stylus/plug installed. Well, upon first listen, I was not impressed. Thin, bass shy presentation. I tore everything down and reinstall/adjusted everything, No change. My first thought was surely Clear Audio didn't voice this cartridge to work only with the cheap ($33 at LPtunes), AT 95e stylus !
Perhaps, letting it run in for a few hours might change things. High hopes I did not have. Well, it didn't take a few hours, but only a few sides of record playing. I've never had a cartridge change so dramatically. Day/Night difference. It will be a few days before I get to compare it to my other Wood (the Sound Smith version). I can say that I am impressed with the added midrange clarity that is now quite noticeable.
The Jico was money well spent, but not an operation for the faint of heart. I had considered transplanting the cheap AT95e for practice, but if "smart" was something I practiced, I would have bought a stylus guard many months ago. Thanks to all that brought this stylus/plug transplant to our attention. Fun exercise. Updates to follow.
Regards,
Don
Hello Timeltel, i think Kentucky and area got blasted with snow weeks before we did here in Canada, well where I am anyway.
Regarding plinth material I helped out on a few projects the most recent were two VPI tables, one a TNT 4 and a Superscoutmaster both belt drive. The factory plinths and feet were discarded and replaced with two layers of 30 mm thick B25 Panzerholz laminated together in combination with Newplast plasticine as damping test done on that stuff on Audioqualia site.
This elevated the performance of these tables according to the owners especially notable was the superscout master which may erk me to find a used one to modify, but I have to directly compare to my tables before committing, this winter.

So one alternative material that is high lighted on Audioqualia site.
I don't know what type of panzerholz Albert Porter uses for his plinths but he was willing to spend 10 times the amount for this alternative material after experimenting with other material.
Timeltel this spring I will have some more b25 panzerholz if your interested in installing your Pioneer dd table and arm in some.
I would never do a plinth in acrylic. The genesis of my interest in this arcane subject is that Clearaudio once made the claim that their pure acrylic plinth had favorable resonance characteristics (the definition of which could be almost anything any audiophile wants it to be), because of its piano-like shape per se.
And, as I noted, they have since abandoned this selling point entirely in that their most recent generation plinths are in essence rectangular and use materials of several different types in order to achieve CLD. I always wondered whether their earlier claim for their pure acrylic plinth had any merit. It does seem to me that a highly irregular 3D shaped object made of a single pure material might (or might not) ameliorate resonant peaks just due to shape, but I know of no theory that treats this subject.
Regards, Lew: Western Ky. Sometime today I'll clear the 6' drifts from the driveway & re-engage with civilization. Meanwhile music has been good. Have been watching the gauges, beginning to *imagine* an association between humidity & level of (this) listener's involvement.

Congratulations to you & Mrs. M on your anniversary. :)

The majority of information concerning resonance (that I've found) is largely oriented to the realm of either physics or architecture resulting in analogies rather than conclusions.

If considering acrylic, a couple of DIY plinths illustrating application:

http://www.audiokarma.org/forums/showthread.php?t=405770:

Peace,
Timel, Where are you located? Indiana? We had snow this morning and then torrential cold rain ever since. Yuk. But my wife and I just went out and had a fabulous French dinner in Georgetown to celebrate our anniversary. Hooray for us.

The pages you cite do not address the issue of shape, except to say that panel thickness of a given material affects resonant frequency, inversely. But the assumption is that the shape is that of a homogeneously flat panel. Shape is what I am interested in.
Regards, 'ol #9000: Eight inches of snow accompanied with 35-40mph winds served to dampen the jollity of visitors and guests, leaving time to consider a reply to your query concerning any association of Young's Modulus, speed of transmition of vibration through a solid and the effect of plinth geometry.

Rather than reinvent the wheel through summarizing, a reference to another source:

http://qualia.webs.com/plinthbuilding.htm

http://qualia.webs.com/plinths.htm

and:

http://audioqualia2.webs.com/rawdata.htm

Best wishes (all) for an even better new year,

Peace,
Dear friends: Speaking of our audio/music hobby and now that the 2012 is just at the end and looking for what happened about I can tell that with out doubt this one was and is my best audio year I can remember. Of course because I " walked " throught with the best persons I could that where all and each one of you. I learned a lot and enjoyed any single post in this thread and other threads from you Agoner's.

In the other side I never imagine when this 2012 started that I could ( trhotugh it. ) achieve the quality level performance that I'm enjoying in my audio system, I just can't even dream that this could and can happen because at the begin of this year the system performance level was IMHO really good and IMHO too nearest to the top as ever.

Right now, I enjoy the music at other level and today I know for sure that exist a lot more information in those grooves that what we normally think.

To appreciate that we only have to work in the whole audio system and I mean in each one and all the links that conforms the complex audio system chain with out forget the room/system relationship and with out forget that the live music is always an excellent reference point to any audio system evaluations.

I'm sure that the kind of experiences I had and have this year were and are similar of what you had and have too.

We have to be congratulated for that!!!°!°!!

Regards and enjoy the music,
R.
Dear friends: Final stage/step on the SR20 fuses " film/picture ".

I changed the four ML fuses ( these ones in the internal power supply stages. ). To make this task I have to open the ML amplifiers ( take out two face plates. ) because there is no acess from the top of the ML.

This could be an " easy " task on normal system ampliifers set up but my ML's are hard wired input to output at both " sides ": signal and electrical, so it is not an easy task to do it and in the other side I have to make it by my self ( stand alone. ) when each monoblock has a weight over 40kgs.

Anyway, I made it and not a single doubt: worth that job, the rewards came inmmediatly.

This last step was the fourth step and in each one the audio system received benefits with unexpected improvements for the better: not different quality performance level but a better one, always.

What happened this time: well, overall distortions gone even lower given the whole system presentation a better accurate tonal balance, transparency, better dynamics and an unherad before music detail at micro and macro levels. Both extremes of the frequency range improves given the music the " immediacy " precense that only the live music has.

The whole experience in my today system is a really NEW experience that I never had before in any of several audio systems I heard.

The level of neutrality ( near cero distortions/degradations. ) of the system is just astonishing and if you are not accustom at this very REAL kind of audio system experience maybe you could think something is wrong down there.
I say this because that's what I experienced and I have to " investigate " more in deep ( through more listening tests. ) what was happening there.

I invite two of my nearest audio friends that have " difficult " ears to satisfy ( each one in different time. ). In both cases they were surprised why the quality system performance level was " degraded ", why my before system losted its " live " its sparkle performance level.

In fact nothing was losted but distortions, every music nuances are there but in a new dimension in a more real dimension in a more " live " dimension.

Today if you listen to the Nardis track on the P.Barber Cafe Blue where through the track the cymbals sound from the left side of the stage are really " busy " once and again there are times where what you heard on those cymbals grooves are a very alive smearing sound that impose to the music performance a grade of " dynamics " that we can take as " alive ".
Normaly through those cymbals sound you are hearing " sound " from the harmonics more than the fundamentals, sometimes because the speed of each and the next strokes ( one after one. )on those cymbals and some time because the kind of smearing sound.

Today I can hear any single stroke on those cymbals and I mean: any single stroke and now the harmonics tooks definition too, palpability and not only smear. Now you can " touch " that cymbals system sound.
I only heard this kind of music performance at live events.

That's only an example of what is happening. The system dynamic performance is today a lot lot better than before with lower " spark " but with higher neutral and accurate reality .

I made tests with both friends changing the fuses ( the ones that I can change fast. ) for they can take in count what was happening and to confirm what I'm relating here.

Today the natural agresiveness that has the live music is more real than ever because there is not only that agresiveness but a more neutral, precise and defined agresiveness and not only non precise defined " distorted sound ".

IMHO maybe all of you can't understand what I'm trying to explain because mayeb you never experienced but on live music events and translate that to a home system is something that I think we can't " imagine " till we hear it.

Anyway, lower distortions means more MUSIC and more MUSIC ENJOYMENT.

A lower distortions/neutral and accurate audio system permit to evaluate in a better way not only music but any single audio item as cartridges, tonearms and the like. You can have better and truer conclusions on audio item comparisons/evaluations.

Regards and enjoy the music,
R.
Dear Fleib: The 550 fits the PC-440 and I think that AT 440 too.

I don't post yet my Precept 440 experiences because I just changed the last SR20 fuses ( 4 of them. ) in my ML monoblocks that as the other fuses changes makes a difference for the better and I have to re-evaluate not only the Precepts but all the other cartridges ( MM/MI/MC. ) with I used as comparisons.

Btw, I heard the AT 440 in my system ( time ago ) and other system and I found out is a cartridge that not satisfied my " priorities " at both frequency extremes. I would like to try it again if I have the opportunity.

Regards and enjoy the music,
R.
Merry Christmas everyone.

Hi Raul, Thanks for the Precept stylus info. I saw that the PC-550 stylus is beryllium/ML, but didn't know what series it fit. It seems there are 2 versions of the AT-440ML stylus. The orig 440ML/OCC must have stronger magnets than the MLa. OCC Output is higher, yet motors have identical specs.
Regards,
Regards, Griffithds: TK5Ea:

Freq. Response: 10-30,000Hz
Tracking Forces: 3/4 - 1-3/4 grams
Channel Balance 1.0 dB
Channel seperation: at 1kHz 29dB, at 10kHz 20dB
Output at 5cm/sec: 4.2mV
Stylus tip: 0.2 x 0.7 mil nude square shank elliptical
Stylus cantilever: Tapered tube
Magnetic system: Dual Magnet
Vertical tracking angle: 20 degrees
Load impedance: 47,000 ohms
Cartridge Inductance: 1,000mH
DC Resistance: 1,200 ohms
Cartridge weight: 6.8 grams

The TK3Ea is 470 mH, 780 Ohm, .3 x .7 mil nude ellipt, the TK1Ea with a .4 x .7 bonded ellipt. The plastic mount of the 1Ea tends to be susceptible to microphonic influence.

I think you'll find the 5Ea slightly more capable in detail retrieval, the 3Ea less aggressive in the mids. The TK1Ea is entry level of this series, IMHO would do better with the AT7V.

Apologies for the short response (Lew, too), am still short on time.

Peace,
Dear Friends:

M E R R Y C H R I S T M A S A N D


A H E A L T H Y F U L L O F S U C C E S S

2 0 1 3 ! ! !

to all of you along your dearest family.

Sincerely,

Raul.
Dear Grbluen2, your thoughts on the progression are correct. If those 1ea and 3ea were to go to auction they would get far less than what their owners are asking.

I am going to point you back to page 69 of this thread, where Professor Timeltel does a thorough job on describing this cart with multiple AT styli.

Merry Christmas to ALL!
I am quite familiar with the Soundfountain site. It's a nice site but full of one man's opinion and no real science, does not address my simpler question.

Merry Xmas and Happy New Year and thanks the earth did not explode on 12/21. (I had planned to take all my tt's with me, anyway.)
Happy holidays to all,
I have a question regarding the Signet line. I have picked up a used TK5ea, understanding that this cartridge was probably not on the same level as the Tk9__ series. I have noticed several of the lower lines ( TK1 and TK3 ) selling for more than the TK5. I assumed that there was a progression from the TK1 thru the TK9. Did I miss something, and is there a reason the lower models sell for more?

Don
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.
The only homogeneous material in your list is slate. Bronze, brass, stainless steel, panzerholz & acrylic are all alloys or compounds that may be homogeneous or heterogeneous in their grain structure. If you assume for the purpose of this exercise that they are homogeneous then SPZ is in that group. It is an alloy of aluminium, copper, magnesium, lead, cadmium & zinc.
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.
Lewm/Timeltel -
You may be interested in reading up on the materials used in my Final Audio Parthenon VTT1. Both the platter and tonearm pod are bolted directly to a 40kg slab of superplastic zinc alloy ( SPZ ).
The TT was designed to have a rigid loop from cartridge to platter and defined energy paths for getting rid of unwanted energy to ground.
The main plinth that the bearing and tonearm pod are directly bolted to is a 40kg 35mm slab of SPZ – superplastic Zinc Alloy.
This "metal" even though it is incredibly rigid and strong, actually self damps at a molecular level due to it's superplasticity – from 10-100hz it behaves like a HIDAMET at room temperature.
Check out p30-35 in the following link -
http://www.interzinc.org/pdf/zinc6.pdf
Furthermore the profile of the 20kg solid aluminium/copper platter has a "curved" bottom profile from the centre out designed to squeeze or deal with energy deflection.
There is an explosiveness, density of tone and lack of smear from the sound of this deck that I have not heard in any other including the much vaunted heavily modded SP10mk3's. The industrial sized AC motor that came standard back in the 70's with a split phase sine/cosine wave generator and torque controller and driven by an 80wpc power amp probably helps too.
Raul

"About AT its Sibata ones are different than the Line Contact ones or the MR stylus shape even in what AT name it as Line Contact there are variations and diferent quality on the polish of the stylus or grain oriented and the like.

That is why I questioned PickeringUK's use of the term "Line Contact" for their Stereohedron stylus in their ad. They are not the same but different profiles. Same family but slightly different! Actually the Shibata came 1st. So it should be of the Shibata family, not line contact family.

Regards,
Don

Dear Fleib: Before I bought the Precept 440 I heard the Precept 220 but was a dissapoint I don't like it in any way.

The Precept 110 and 220 you can find out every day on ebay but as you pointed out the Precept 440 is hard to find with 440 original stylus and in good condition, I think I was lucky about.

As with some AT cartridges we can use with the 440 the stylus replacement as the one of the AT 440ML.

I bought a 550 stylus replacement and an original AT 440ML to check about but exist one build design diferencen between these stylus replacements and the original P440: the cantilever of the Precept 440 was made from beryllium where the 550 ( even that the seller of the 550 said it it is an improvement over the original P440 and even that owners of those 550 stylus replacements said the same: I disagree with them. The original cantilever per se make a differences. ) and the AT 440 did not.

That single difference makes a huge difference, at least this is what I'm experienced on my tests. Obviously that the stylus shape is not exactly the same shape and this is a diference too but the cantilever one is more " substantial ".

I'm finishing my tests on the Precept 440 and will share those experiences.

Regards and enjoy the music,
R.
Dear Griffithds: No, are not the same. What I'm telling is that over the years when appeared " line contact " stylus shape: Shibata, Stereohedron, VDH 1 and the like many people name it as " lene contact " because all them have a wider stylus contact area with the groove.

About AT its Sibata ones are different than the Line Contact ones or the MR stylus shape even in what AT name it as Line Contact there are variations and diferent quality on the polish of the stylus or grain oriented and the like.

Regards and enjoy the music,
R.
Dear comrade Don, Imitation is usually interpreted as a compliment but this does not apply by the so called 'intellectual property'. Shibata was a trademark while nearly everybody wanted to participate in 4 channel adventure. That is why we got 'Sterohedron' and other peculiar names for the fake Shibatas. The shape is pretty
complex so one can easily change one or the other facet.
Mitachi corp. produced 'the same' cart for the Astatic and the Glanz .The only difference was Shibata for the Astatic MF 100 and 200 with Shibata and Glanz 71, 51 and 31 with
line contact. Vetterone and I were not able to hear any difference between MF 200 and Glanz 31 L (see the Glanz thread). We should also pay atention to the quality of the
used diamonds and the quality of the polishing as Raul already mentioned.

Regards,
Regards, Lew: Simple harmonics:

http://sharp.bu.edu/~slehar/HRezBook/Chap2.pdf

Factors we concern ourselves with:

Damping: The dissipation of a vibration's energy into heat energy. This may also be considered as the frictional force that causes the loss of energy

Quality factor: The number of oscillations required for a system's energy to
fall off by a factor of 535 due to damping where quality factor, Q, is the number of cycles required for resonant energy to fall off by a factor of 535. Given is e2π, where e=2.71828, the base of natural logarithms. An interesting perspective on composition: http://www.principlesofnature.net/number_geometry_connections/more_resonances_between_musical_and_visual_scales.htm

Driving force: Any external force that pumps energy into a vibrating system

Resonance: The tendency of a vibrating system to respond most strongly to a driving force whose frequency is close to its own natural frequency (eigenvalue) of vibration

Steady state: Behavior of a vibrating system after it has had plenty of time to settle into a steady response to a driving force

In the example of the CA deck, consider wave cancellation. Hypothetically, as turning point resonances travel axially in sinusoidal form, and if introducing irregular geometry reduces amplitude of resonances through reduction of overshoot, it seems (to me) a structure might be designed so that turning point resonances encounter driving point resonances in a cancelation mode. Your thoughts?

This math would fall into the realm of physics, my math is so rusty even my calculator squeaks.

How might all this effect what I'm hearing with the cart Peter Leddermann waved his musical wand over?

An AT-ML150 OCC, the generator can is fixed to a ceramic mount. A sapphire cantilever has greater mass than boron but is more rigid, IIRC self resonance is 16-17k, boron at 12k. Beryllium by mass is heavier than boron or crystal but a typical Be cantilever's eigenvalue is near 19k. Be aware this is from memory.

On a Yamamoto HS-2 headshell & tied to a graphite "S" arm, resonances are damped rather than dumped. In architecture, boundary and air borne resonances are a concern. Think parking structure. There are not only the acoustical resonances (echo), but also the (imagine) mechanical rumble of passing traffic. In less utilitarian settings this is undesirable, constrained layer damping (CLD) is utilized. Shown as most effective, the introduction to a structural component by cladding or interruption by an alternative material is the most effective means of address. Efficiency is improved with integration by bonding or layering. Layering is most effective if, when there is a grain structure, laminations are oriented at 90*. Resonant waves don't like to make turns. As wood has both axial and lateral elements and space exists between these longitudinal and latitudinal structures the resulting effect is one of dislocating resonances.

Cut to the chase. Resonant chain: Saphire cantilever, suspension, Mu metal can (sounds like something from Edgar Rice Burroughs), ceramic mount, cherry wood headshell with a bronze plate above. Headshell arbor, graphite curved arm, silicon fluid damped PU-70 arm transitioning to a sturdy laminated wood plinth. Damping is effective.

The stylus is SS's optimized LC, tracing faults are not evident. Nuance and detail, initial transients and decay are quite acceptable. Output is 4mv, output impedance a good (to my ears) 530 ohms. Insturments are heard as entities rather than agglomerative. Coils are wound with OCC copper. In comparison, high purity copper has an estimated 1500 grains per foot. Grain boundaries tend to introduce distortion. Oxygen Free High Conductivity (OFHC), 400 grains per foot. Listen closely, there is a definite improvement in clarity. Dynamics are also more apparent. Linear Crystal (LC-OFC), 70 grains per foot.

Ohno Continuous Casting (OCC) or "UP-OCC" (Ultra Pure Copper by Ohno Continuous Casting Process) was developed by professor Ohno of Chiba Institute of Technology in Japan. The process involves a heated mold continuous casting resulting in small rods of OCC pure copper. Wire can be drawn which can have Copper grains of over 700 ft length.

Bass is vibrant, full and with dynamic impact, decay is precise and without bloom. Upper mids do evidence a forwardness in apparency, there is a consequential impression of clarity and resolution. Hfs are nuanced and with excellent detail.

I do miss my favorite resonances.

Peace,
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.
Hi Raul, I'm wondering about the Precept 440LC, have you had a chance to listen to it much? I think these might be rare, I've never seen one. Does the stylus fit any other ATs? Apparently there was also a Precept 550ML. It would be interesting to explore these, but they might be hard to find.
Regards,
But the point is whether shape can spread out or smooth the resonant peak of a homogeneous material. It is easy to see that shape can shift the resonant frequency per se. I suppose it can also spread out the energy so that several adjacent frequencies are excited each to a much lesser extent, and it makes sense that an irregularly shaped object could behave in such a manner, but I wanted to see the math/physics that describes and explains that. But if it's true, then Clearaudio was once on the right track that they have since abandoned in favor of CLD.
Regards, Lewm: It's a simple concept, the math is more than I want to tackle. Resonance is the result of an external force vibrating at the same frequency as the natural frequency, or eigenvalue, of a system. Resonant modes oscillate back and forth axially as helices between two turning points.

This illustration has been offered previously: Consider a clap of the hands in a square, empty chamber, then in a pyramidical or spherical chamber of the same volume. Axial reflections may actually increase amplitude of unintended resonances (ringing), because they lack parallel surfaces, irregular geometrical shapes disperse resonances.

By definition, he point of origin is the drive point. Transfer point measurements can be taken when attempting to identify boundary resonances. Doing so will identify both phase shifts and coherency. With this information, one can develop operating deflection shapes to minimize boundary resonances.

From this thread, post #7405:
"Boundary conditions do effect the resonance frequency. The resonance frequency is influenced by Young's modulus, and geometry. --- resonance characteristics (of a beam) are determined by: 1. Young's modulus, 2. The cross-section. 3. The mass per length. 4. The associated eigenvalue, or the self-resonance--- as described by the preceding factors.
" There is a probability that not just the primary tone but also the second and third overtones are also excited. Measures to correct this are selection of the material itself, damping--- by external or internal applications, by tapering or curving---". This conversation applied to tonearms.

"Music will depend upon a synchronisation and resonance of many parts and wholes and upon a radical rethink of how we can more harmoniously relate the units of geometry and number." (W. Roberts, 2003.)

Peace,
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.
Raul,

"There are several manufacturer " line contact " versions. It's right the name " line contact for them ? well is IMHO not important what is important is that as the Shibata or the analog-6 or even the MR the Stereohedron has a wider groove contact."

The Signet TK 7SU is a claimed to be a Shibata tip by Audio Technica. Their TK 7CLA is claimed to be a Line Contact. By your above quote, then they both must be the same stylus! Are they? I have both and they sure don't sound the same to me.
Regards,
Don
Dear Dover: Something like that was what Cardas made with its cartridge wood body build by Benz Micro and where the BM has not the wood body " holes ".

It is obvious that those " changes " on the build material makes a difference because change its resonances frequencies and how those resonances travel and " broke " through its " trip ".

That's what happen with tapered cantilevers and tapered arm wand tonearms and even on tiny shape differences on headshells.

Regards and enjoy the music,
R.
Ughhh! I actually wrote that. Who knew? I guess you did. Are you archiving my wisdom or lack of same? The term is still rather oxymoronic, even if I wrote it first.

While there are good practical theoretical reasons to eschew wood for a tonearm, I admit I like the Reed a lot. And my one audition of the Talea in someone else's system, but one that is very similar to my own, suggests it is also very fine.

When I look at the Grace 714 and then at the new Durand Telos, I see a lot of similarities, except the Telos obviously is a more sophisticated approach that pays attention to azimuth and VTA adjustment, and the Telos is the subject of cult worship. This makes me wonder whether one could squeeze a lot more performance out of the Grace, if one were to tweak it here and there.
The Guarnerie suggestion is pukka. Recent studies have indicated that the imperfections, variations in wood thickness, irregular holes, patched wood panels & tweaks to the original instrument are generating that unique sound. The headshell tweaks are a matter of taste.