Standards Aplenty
Flashed all their experience with care Flashed all splitting the philosophers' hair Laying before all their thoughts with care Speaking audio truths where others only wondered Plauged by Hegel's intermnable pen stroke Disdainful of the ancients, of Kant they spoke Of tubes and proven vintage and where cascoded blundered Measurment or implementation They charged forth and back You must fix said each What the other had sundered. The 980 your kidding pray tell The pragmatist with shock, it fell? You SOLD it, a thought from hell FOOL what were you thinking the blues O well Get pickering D3000 through 7500 and hold fast you rue replacement cost as the day you were born. no that doesn't make sense. said the gipper send it to the tipper and maybe dog nipper will bark his approval to you forget not the goo fix the tip in lieu of gooey super glue Its solvent will take out the plastic and you will no longer fake for heritage sake the sound of the one not half bake. Methodology one and all the cart did fall a wheel broken is now a plough The cart pushed the horse as it got loud and loud to fill the hall said one and all we are having a ball even though we Kant hear I know not what said but please pass me a beer.
|
Dear Professor, Exactly what I meant by your prose; your post from 06-15-11. There are foreigners among us, you know, and you should also, I quess, not assume that your Anglo&American readers have all a degree in English literature(grin).
MM regards, |
Alas, Alack By Fleib I'm outdone Off to the hall Some beer and some fun So much thought So much consternation From this sobriety I must vacation |
Dear Lew, Some added info about 'your' Sartre. He was also accused by the French C.P. to be a 'petit bourgeois'. I am familiar with the communist terminology and even with Marx 'surpuls value' theory but I was never able to understand the importance of the prefix 'little' before 'bourgeois'. I always thought that the communist were only interested in 'huge undertakings' so this little bugger caused much trouble .''Whay deed they not used 'huge bourgeois' in stead '' , I thougt. Then by, say, comparition with a 'huge capitalist swine' one would be able to explain what the fuss is about? But what can you do with an comparition with an 'little capitalist'? But you know Sartre has luck to live in France. Even de Gaulle defended him and stated something like: 'the French will never arrest our Voltaire'. In the East bloc however the situations was very different. The (dis)qualification 'petit borgeois' was worst then the death penalty. Ie if you were 'normaly' death then there was a at least the chance that someone would talk about you. But no chance that anybody would talk about you if you were 'petit bourgeois'. So,dear Lew, with your public admission regarding Sartre you may be in trouble. I hope that there are no real communist among you friends.
Regards, |
Pls. no vacation - at that stage it has reached such a fantastic niveau! it is hard to believe that the philosophers among us need any lecture any more...
best & fun only - Thuchan |
Hi Raul, do you have any chance recently yo hear your AT24 cartridge? I sourced original body and styli and I'm pretty impressed by it. |
The 980 and 981 are the same cart. The 981, if there was one, came with a matched stylus. I'm told that the low output is far superior. I don't doubt it. This came from as guy called desktop, a pro who used to post on VE. I suspect that any who prefer the high out have inferior hi gain capability. The 7500 is the Pickering counterpart to the 980. The specs are identical. The stereohedron is said to be similar to a shibata. The whole stylus assembly is the weak link imo. That's seems to be true with virtually all carts with removable stylus. Fixing the assembly to the body is mandatory for optimum performance. With an output of 0.3mV, there is virtually no inductance.
Mine will eventually go to Soundsmith for a ruby/micro LC. The only saving grace of the orig alum cantilever is the short length. Shibatas sound soft in the extreme high end. That can sound nice but it's all in what you like. ATs seem to sound better with the plastic stylus holder removed like a Clearaudio. All the voodoo and witchcraft gets a little tiring. It's not all that hard to figure out what does what. Deciding what you like is much harder I think. Most of us have a wealth of good stuff.
One of the main advantages of a MC is the cantilever is fixed. That's also cause for concern. It makes the mounting and arm more critical with respect to vibration and energy dissipation. The MC is the ultimate cart as far as dealers are concerned cause it demands much more high dollar sales. Many do think the MC is the ultimate. At this point I really don't care. Even though 99% of my listening is jazz, I can hear a difference between a good and a better cart. Is forgiving a trait of compromised performance? If so then I think we need different sounds for different records. My records are all over the place and unless you're one of those guys who play a few audiophile records, yours are too. Regards, |
Dear Fleib, I assume then that you own a 980LZS. Yes? I am listening to mine in the L07J tonearm which is the installed tonearm on the Kenwood L07D turntable. It does sound a bit reticent in the highs, but I cannot tell whether that might be due to the old (Litz) wiring in the L07J and the connectors in the signal path. To me Litz wire typically sounds a bit that way per se. In any case, I have no complaints with the treble performance. I am waiting for an eruption from Raul, to your remark about the hi vs lo output versions of the 980. I have never heard an HZS, so I have no opinion about how the two compare. |
Dear Lewm, Yes, a couple of years ago I was visiting the KAB site and happened to go to the cart section. Kevin was selling the 980 in both hi and low. I didn't need Desktop's recommendation to choose the low. BTW, he thinks the 980LZS might be the world's finest MM. I don't know about all that. I know that I like it. For around $100 I got the body and for an additional $80? I got a Pickering D3001. That's a .2 x .7 ellip. I also have a Jico D81 bonded shibata. The Pickering has more finesse. Kevin at KAB told me that the Stanton is the finest tracker he ever had on a 1200. It was the only cart he tested that could complete his torture test record.
That's a wonderful table you have there. I have a couple of Kenwood DD, but not an LO-7D. Maybe you're just using the arm? I suspect your termination, tranny or load, might have more to do with the character of the sound. It was very strange for me when I first played the cart. I have an AHT prototype phono stage. I loaded it at 100 ohms, 67dB gain and got only midrange. It was the best midrange I ever heard. Funny, as I changed the load and broke in the cart, that same midrange wasn't quite as spectacular any more. Glorious by default? I took it up to around 2.4K. After it loosened up, somewhere around 270 ohms does the trick. Like some LOMC it gets more dynamic with higher value load and more focus with lower. This seems to vary a lot with preamp and system. Manufactures could make it easier on MM/MI users by providing options. Hi out carts would be much more desirable if users could load and tune to their system. They think everybody is looking for the holy grail. Most times I just want to play a record and have it sound really nice.
If Raul prefers the hi out, I don't see a problem. We all get different results to some extent. If someone likes a TK-7_ does that make it wrong? There's really no morality involved in all this. Maybe the one who likes the Signet will try a 20SS and like that more. Maybe not. Regards, |
No. I've got a full-up L07D cum L07J tonearm that I like very much, not just the tonearm. I found that the table itself sounded much better after I installed an EMI/RFI shield under the platter mat (termed a "platter sheet" by Kenwood). I used TI Shield available from Mike Percy. I have been meaning to try it with my other dd turntables, but for sure it is a must-do for the L07D. The idea was not mine, came from reading the L07D owners website. The leader of that group uses ERS cloth. If you still have your Kenwood, you might give it a try too. |
Regards, Fleib: Good post, a lot said with an economy of words. As there are some who are detail oriented, the VE cart. database does show three 981's, two HZ's and one LZ. The stylus contact area for the stereohedrons is given as 8um (minor radius) x 71um (major radius), consistent with Shibata but according to it's "inventor", a Huges Diagmatics Inc., it has two additional front facets, intended perhaps to either reduce tip mass or to avoid infringment of the Shibata patents. As a comparison, engagment for a .7mil conical or standard .3 x .7 elliptical is frequently given as 18um (major raidus), a microline at 75um. These are AT figures, they also state their Shibata as 6um (minor) x 71um (major).
Reflection on these figures and it's relation to groove modulation might give one insight into the noted hf response of the Stereohedron stylus.
"One who truly knows---can never be impoverished". Sun-tzu.
Peace, |
Lewm, Lucky you. I've seen a couple of 7Ds sold here on Agon for ridiculously low price lately. ERS cloth is a great idea. You can get it with adhesive backing. Put it under a delrin mat and you'd have the ultimate interface? Built in constrained layer damping sounds appealing. Perhaps a contact points interface would be the only competition, but that's for belt drives.
I used to have a Studietto w/zeta. That was my fav. The suspension was the weak part, but I was in the biz and had all kinds of extra springs. My ex partner had a Reference. That one was fun. One thing I learned was how to goose decent performance from even a modest deck. It's a lot easier if it spins at the right speed. Some of the entry decks are like a money pit of a house. If you're on a budget, who wants to spend a grand or whatever, on a box to make it run at speed? I'm thinking of making some videos on modifying tables. But like my Sapphire/Teres rim drive project, it sits on the floor barely touched.
I have tweeters to install, an open baffle project and a full range driver idea is formulating that might really take the cake. This is a hobby for me now, if only I could squeeze a few more hours in each day..... Regards, |
Thank you Timeltel, I started investigating the differences in tips a few years back. This necessitated using MM/MI carts for obvious reasons. Although I wanted to approach from a standpoint of "no preconceived notions", it's impossible to put aside what you already know. The AT micro line is the same as a micro ridge. These are cut in the same facility in Japan. There are only a handful of places in the world that cut diamonds for tips.
The shibata was the first extended contact shape, invented for 4-ch reproduction. It sits near the bottom of the groove. Even if a record is cleaned well, it might reveal some noise when deburring parts of the groove previously unplayed. Because the facets are different on front compared to back, the contact with record spinning is curved rather than straight. I believe this is what gives the shibata the uniquely sweet high frequency sound. From a technical viewpoint it could be seen as a flaw. I suspect the delay is less than the difference in transient response between some cart designs. I admit I never tried to calculate. I think this invention is more of a stroke of artistic genius. Like it or not, it is or was unique. Some approach this as calculating the trajectory of a rocket. I try to approach as how does it sound?
Of course the side dimension is the detail extraction aspect. I tend to go for very detailed. It seems that many prefer musicality or overall coherence over detail.
AT offered a great way for me to learn the something about the art of cart design. Once you can do stylus/plug transplants, you're not limited to body style type substitutions. Choice of tip, cantilever and compliance applies to all carts, not just MMs. Another Agoner, Glrickaby, seemed to discover the Clearaudio/AT relationship, and post in on VE and Audio Circle with me.
There are other things you can do as well. I have a potted AT-95 with an aluminum top plate. It sounds pretty damn good. Right now I have an AT-7V tip on there. I keep it in the same plug and can swap with my Virtuoso. But don't think the Clearaudios are the same as a AT-95 body. They're not. They have different generators.
There's no such thing as 47K being the standard for terminating a MM/MI. It's only there by default. "They" perpetuate this mentality to sell carts for thousands of dollars. Those carts are fine if that's what you're into, but offering no options for the rest of the people is a conspiracy of indifference or greed. Regards, |
Regards, Fleib: Would you be so kind to describe the proceedure involved in mounting your AT-95 to a solid top plate? I have a spare Azden YMP-50VL & suspect it would benefit from an improved mounting application, thinking a solid block? General details would be appreciated.
Peace, |
Dear Fleib, Empirically, I would recommend against the ERS cloth and in favor of the TI Shield. For one thing, ERS cloth can be kind of lumpy; the platter sheet might not sit perfectly level on it. For another, the ERS cloth would tend to decouple the platter sheet/mat from the platter and thereby abrogate the designer's intent as regards dissipation of energy from the LP. But most importantly, TI Shield just measures way better for both EMI and RFI rejection than does ERS cloth. However, I have not compared one to the other. TI Shield needs to be grounded for optimal effect. I figure that is achieved via the large contact area between TI Shield and both the platter (below) and the platter sheet (above). |
Timeltel, I made it out of an old aluminum headshell, using the old slots to align with the mounting bolts. It is fixed with epoxy. A broken keyboard is forcing me to use an old one whhhhhhhhhich had coffee spilllllllllllllllllllllllllllllled on it. lol, I'll have to get back to you.
http://www.audiocircle.com/index.php?topic=88878.0 |
Dear Thuchan: Finally I have a little time to give my answer- opinion ( btw, I need to post my answer to Halcro/Chris one and to Fleib on inductance. I need more time but I will do it. ) on your post about Common listening Aproach ( everything from here are in good shape and not against you. I respect you and you like me. Nothing personal. ) ):
++++++ " if we all would be a peer group knowing each other personally and also having had the chance to listen to each other system we might get closer to your objective parameters. I understand your approach finding comparable preconditions and to counterbalance them over the distance. Only I doubt it will work.
Regarding the EMT JPA 66, which is a pre-amp as well as a complex phono stage, I am in good neighbourhood with some Japanese and German afficinados that this is the ultimate machine. What I like is not only the sound and the variations you may play with, especially when it comes to MM cartridges. No, technologically the two output transformers (which phono stage does carry them) enable a different sound experience you may have with the EMT 139st too. Also the 6 inbuilt SUTs are of such good quality you will throw away most of the contenders...
This is first accurate and best performance......." +++++
Nandric said that both of us have no communication, I don't think so. The main difference is that both have different targets: when for you is enough that you like what you listen through your audio system for me needs not only like me but be accurate ( measure good. )-neutral-very low distortions-no colorations. When you are looking for what you like I'm looking for excellence in quality performance level all over the audio chain. Your trade-offs are way different from mines.
As I posted: I listen ( when driven audio items tests. ) to what I missed, to what is not in " there " or what is " exceptional different ", to what disappear ( including distortions. ), etc, etc. As Doug Sax answered on that Halcro link: " and I listened not so much to its virtues as to its faults ".
I have years posting: " loosing and adding the less to preserve the source signal integrity ", this is my main target. First than all I have to preserve the source signal integrity looking for accurate and neutral audio links all over the home audio system chain.
IMHO today what measure good sounds good too, not like in the old times when those vintage Japanese electronics always measured good but sounds bad, this IMHO does not happen almost any more: normaly what we heard today in current electronics/speakers/audio items is how it measures.
How accomplish or try to accomplish my main target?, other that my knowledge/experience level on music and audio subjects I have to design a " process that help me to understand what I'm listening under audio items comparisons and that help me to identify:different kind of distortions and different distortion levels, colorations, noises and the like " , that's where my process born and came " alive " years ago and over the time was and is " suffering " changes to improve and be not only better but more trusty.
I don't care about my " Japanece/Germans neighbourhood " and only take care about when that " person " has a superior knowledge/skills level than mine, that's it: when I can learn to improve and grow-up.
For years I care not only on my " Japanese/german " audio friemds, reviewers, audio retailers and the like till I take in count that I was not growing up or at least growing up to slow. Somedays one step a head and some other days two.tree steps back and many times only side steps. IMHO something similar of what you are living with out knowingit. My advise about is that you take alone your " road " with no " Jurassic audio gurus " surrounded where you can't grow-up and only are loosing time and money, yes with a lot of fun but loosing at the end. IMHO there is no " signs " of your audio improvements.
Your " Lost Friends " in your virtual system is nothing less than the " Frustration Friends " where sooner or latter your today tube electronics will finish.
I know that you are not looking for excellence performance level on your system and certainly with those " Jurassic Park " audio items is impossible you can achieve excellence.
I will take that EMT Phonolinepreamp that you and your " Jurassic " friends name it: " ultimate machine ". For me an " ultimate machine " must be first than all ACCURATE and NEUTRAL and your unit is far away from there. There are many reasons why your " ultimate machine " it is not an ultimate machine: full of transformers where the signal suffer severe degradation ( the best signal transformer is no tgransformer. ), full of swtichs where the signal is degraded, tube inherent inaccuracies non-neutral colored noisy and distorted technology ( it does not matters design and first rate execution. ).
Dear Thuchan, the RIAA deviation on that EMT ( 20hz to 20khz. ) has a swing of 1db!!!!!!, this IMHO is non-tolerable to any today phono stage: this sole factor made that that phono stage can't " save " and mantain the cartridge signal integrity, instead of that only degrade the cartridge signal with inaccuracies/colorations and distortions that are not on the cartridge signal!!!!, so where you and the " Jurassic Park " seen the " ultimate machine "?. I don't care that you like it because that's not the subject.
The subject is to achieve excellence quality performance level and that unit can't do it. I know that you think that with your new " toys " you go several steps a head but IMHO you only give steps backward or in the best scenario: only a side step, but I doubt this last.
That's why is so important to have a " specific process to audio system/items evaluation ". It is almost impossible to know if you really advance or go back only with that " It's wrong but I like it ", can't do it for sure.
I was really benign with your EMT RIAA deviation because if you measure that RIAA maybe that deviation is over 1db and not only that but is almost sure that the left channel RIAA be different from the right channel RIAA as maybe there are differences even in the line stage frequency range/response for both channels and even its output level for both channels could have differences too. I know what you are hearing not only because this EMT and your Wavacs but for what you report, example that you like it the TK3e. I can understand this because youare a rockie on MM/MI cartridges but in other areas you confirm what I'm saying.
We all know that analog is an imperfect medium but we don't have to increment those imperfections on each audio link that like the phono stage and say: " I like it ".
Accuracy is the name of excellence, with out accuracy it does not matters " how good it sounds ". Don't you think that is way better that something be accurate to the signal and at the same time Sounded Good?, certainly yes.
This is an example of the excellence level I'm looking for and that I already achieve with some of my audio items ( I'm not saying I'm done but I'm trying hard to be " there ". ):
https://picasaweb.google.com/104284617601331669309/1606201109?authkey=Gv1sRgCNrBhveq5uzC-AE#slideshow/5618984106525365922
that is the RIIA deviation ( both channels. ) on the phono stage I use.
https://picasaweb.google.com/104284617601331669309/1606201107?authkey=Gv1sRgCI3hj-juiKXOGA#slideshow/5618983008834878562
those are the same RIAA measurements on two top SS Phonolinepreamps.
Remember the 60K Phono Stage only german Vitus?, well it is not better.
The RIIA accuracy on my latest unit measured: 0.012db!!!! both channels!!!!: no differences in between.
This is only of the excellence example level I'm accustom and looking for.
No, you and me ( as many other persons in this forum. ) are listening different " things " and not because we don't: """ knowing each other personally and also having had the chance to listen to each other system we might get closer to your objective parameters. " ++++, but because your trade-offs ( for say the least and be polite. ) are way different from mines.
Excellence against " I like it ".
Regards and enjoy the music, Raul. |
Dear Raul, agree with you we need not to rely on Gurus or writers` opinion. What I am saying is: I know some people in Japan and Germany who are deep into our hobby and they have real contact with the JPA66 and made their own experiences rather than looking from the distance onto this unit.This is what I am interested in also trying to comprehend the engeneering concept as well.
That was a LOT of words to say that "my JPA66 is 'bad' ". I also agree with you we have maybe different tastes on equipment and listening enjoyment. I rather go for lively, emotional sound, no neutral or clinical clean waves or flat in terms of frequency response.
the tubes vs. solid state issue is also a kind of development I would say. You stopped looking or experimenting with gear five years ago you said. I do respect this as I understood you have reached nirvana. I am pretty sure we both will become happy "in our worlds" and the only step forward in our exchange might be a real test in font of the systems.
best & fun only - Thuchan |
Dear Raul, I will not take any side here, but I just want to recommend to everybody's attention once again the ultimate statement by J.W. v. Goethe regarding individual human preferences in all aspects of personal life:
"erlaubt ist, was gefaellt, was sich ziemt" ( from: "Torquato Tasso" by J.W.v. Goethe).
The more simplified english "each his own" comes close, but doesn't capture the full content. As such, even the experience of "absolute sound" as well as "quality" is - unfortunately ...;-( ... - always in the eye, ear and mind of the individual beholder. In other words - everyone of us is living in his/her/its own and singular universe. Thuchan's position is as good and valid as yours (... or mine...). None of us has any right to judge nor criticize the other's position or taste in sound. Each a universe none of us can share nor fully explain to the other. The dilemma of every audiophile striving for any absolute ..... Too bad. Best regards, enjoy the music and fun only, D. |
Dear Halcro,
finally I received my TK5Ea and the silver connectors. All put together with the new AT155LC stylus in an appropriate SAEC shell leads to a wonderful result in the FR-66s.
I have figured out, also with the TK3E and the TK7SU, if you are using the right headshell/MM cart combination the FR-66s is one of the best arms for MMs. The TK3E gets some more soundstage in the highs when using the No 3 stylus of the TK7SU. Nevertheless it provides a wonderful punch as we agree on. Many thanks again for the recommendation on these 2 carts.
I experimented a bit with MMs, also with the "new giants" and was able to get some nice sound out of these carts. Some are providing an airy sound only, which is ok for voices or small instrumentation but not for the big orchestra and "the real music". This might be the reason why MCs are so popular.
Understanding the MM-shopping became a bit of a game for many MM-afficinados due to the reasonable prices. You can easily throw away the one you don`t like or put it back on ebay. I guess some of the MM-guys writing on the MM thread just do this, why not?
We should not forget the London Reference, a Moving Iron of benchmark quality. Maybe some of the MMs discussed here would lounge reaching it`s overall qualities. |
Dear Raul, Since it is OK for you to rather harshly dismiss Thuchan's phono stage, and indeed his entire downstream amplification chain, and since it was OK for you to categorically dismiss vacuum tubes as a way to amplify music, I hope you will take it with equal grace, as Thuchan took your remarks, when I ask the rhetorical question, what are you listening to? Answer: You are listening to sound coming out of your speakers. You are not listening to your preamp or your modified Mark Levinson amplifiers. They are just generating complex AC signals that need transducing to be heard. How on earth did you select those speakers and that subwoofer, if your goal is as pure as you say it is? I posit that you made your choices subjectively. You are trapped, just like the rest of us, with your ears and brain. There are many many other speaker systems that would likely have lower distortion and flatter response than does yours, that employ much fewer distortion- and phase anomaly-inducing crossover components than does yours. Your whole rationale for stating that you operate on a higher plane than the rest of us falls apart when I consider your speaker system. But it's OK. I respect you anyway. I am with Dertonearm on this. |
Dear Thuchan: This is the second time in this page that you " receive " my personal opinion with " grace ", I really appreciated that because I don't wait nothing less from you.
I have to go now and come back when I have time.
Regards and enjoy the music, Raul. |
Dear Dertonarm: You know I respect you and in some ways I could agree with you on this subject. More on this latter.
regards and enjoy the music, Raul. |
Dear Lewm: I understand perfectly your point of view. Please read about:
http://forum.audiogon.com/cgi-bin/fr.pl?eanlg&1200430667&openflup&3941&4#3941
I'm not saying is perfect faraway from there but extremely competitive with yours or any other person in this thread or outside it. Btw, I'm not dimished nothing but when you " see " things with a little of objectivity things are different on what you supposed.
I have to go to take my flight on time.
Regards and enjoy the music, Raul. |
My favorite Goethe (in youth) was "The Sorrows of Young Werther." This was a double-edged critique of a poet/philosopher's romantic self-absorption. Goethe later recanted the book in light of a large readership of educated German youth failing to detect his irony, with a few even fulfilling the plot line of a romantic suicide pact. As German philosophers are popular around here, a note of caution lest the romanticism of the MM phenomenon consume us all. |
Dear Dgarretson, The French enlightment caused very different influences in Europe. The 'essence' was about the 'eloquence' but with different understanding in different countrys of what this means. In some countrys like Russia it meant 'well -read' or literature in other the science. So the dream of each Russian intellectual is to become a second Tojstoj or Dostojevski. In Germany it was literature + philosophy. So both , the writers as well as phylosopher, are in high esteem in Germany. No wonder then that Dertonarm whom I regard as one of the most eloquent person I have ever meet is refering to Goethe. Alas as Frege explained the literature is an art and not a science. Ie the so called truth values are not involved in the literature. Ie you are free to write a fantastic poem about the beauty of the Pegasus wings without any worry about the existance of this imagined animal. In science however it make no sence to attribute whatever propertys to a non existent entity. That is btw why we spend so much money for this colider in Switserland . If this higs particle does not exist the whole theory will colapse. Exactly what Frege meant with his 'About Sense and Reference'. So to my mind this reference to Geothe is not convincing at all. Regards, |
Dave, I think the latest fracas is about how one selects one's components downstream from the phono cartridge, be it MM or MC or ceramic, even. As you know, I keep some good MC cartridges around as a reference. But even so, I am far from drawing any global comparisons between the two archetypes, because I have not heard many/most of the "very best" (i.e., most expensive) MCs and may not ever be able to do so in my own home system. Another thing is that we tend to lump MM and MI cartridges together. I think they may sound distinctly different but more like each other than like a good MC. |
Dear Lewm, MI cartridges are a group of its own, good that you name it. It is a completley different design. But in the end we have three groups and if someone would ask me "what are your Stereo-Favourits of each group" I would mention: Lyra Olympos, AT TK7SU, London Reference. Of course there are many other excellent contenders.
best & fun only - Thuchan |
I must must hear an Olympos. It is such a revered cartridge, and by people who have everything and have heard everything. |
Hello Timeltel, Sorry about that post last night. The 2nd set of pictures at the AC link I provided, above, shows the 95 with mods. I didn't want to add a lot of mass, that's why I used a cut down aluminum headshell. The epoxy holds it rigidly in place. This is the same 5 minute gooey type epoxy I used to pot the cart. Near the back-top of the cart is a screw that holds the plastic top to the body. I removed the screw and gently pushed the epoxy into the body. The plastic top was damped with rope caulk and glued on to the body. I pre-cut the headshell and glued that on to the top. Others have reported that potting the inside of the cart makes a significant difference. I figured that reducing or elimination internal vibrations could only help. It does seem to make a nice improvement on the 95. It seems quieter and more like a master tape sound. The other report I read was on an AT-14. The 95 is inexpensive so I didn't mind risking it for the experiment. The danger is with the delicate wires going to the output pins. I'm thinking about doing this to some of my others, but haven't yet done so.
Running near the front of the AC vinyl section is the thread on phase shift. Although it is lengthy, I think you might find it interesting. Regards, |
Hello Lewm, I really have no experience using a RF/EMI shield on a platter. I never had a problem in that regard, but I would imagine it could be something that you might not realize it needs fixing until you hear it w/o interference. Is that the case? My thoughts were more about platter design and energy dissipation. I very much belong to the Pierre Lurne school of energy dissipation. There are about 1/2 dozen interviews with him on the net. One platter is a sandwich of 9mm of lead between slices of delrin. This is designed to reflect back at different times and break up reinforced reflections back to the record. Regardless of original intent of Kenwood designers, some things can be improved. Regards, |
Regards, Fleib: I did follow up on the provided link, nice discussion you guys had going there. Thanks.
Peace, |
Dear Fleib, I did not know that Mr. Lurne' founded a school. I do know that I heard one of his early turntable efforts that had a spring suspension, and I thought it was a very bad sounding, over-priced product. Possibly his later efforts have been better; it would have been easy to improve the one I heard by tossing out the springs. The thing was visibly bouncing whilst trying to play music. (The suspension seemed completely undamped.) But this is all OT. Yes, the platter (and platter mat) is a very important and often neglected determinant of turntable sound, IMO. There are as many opinions on how to make the perfect platter (and platter mat) as there are audiophiles. The negative opinions that some have regarding the vintage Japanese dd turntables may have as much to do with their typical heavy, dull-sounding rubber mats as anything else. First thing to do with a Technics or a Denon is ditch the mat (but keep it hidden away, for originality). And yes, the shield is something that you don't miss until you install one and hear the difference. I would not run my L07D without it. However, I think the shield is likely to be specific for dd turntables and maybe only for Kenwoods at that. Some guys were going to try it with Technics tables, but I never read a report on the results. (The better Kenwoods have a coil-less motor that is mounted right up high just under the platter, so my completely unproven theory is that the motor may radiate EMI upward and affect the cartridge.) |
Dear friends: Good opportunities :
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Regards and enjoy the music, Raul. |
Dear Dertonarm, I need to make some 'a posteriori' comment on your Goethe quote. As a lawyer I know that nobody, except some specific lawyer, read Criminal law. There are two reasons why: 1. the language used is very boring because of the repetition of the same kind of hypothetical statements. a. If you commit 'a' you get 4 years; b. If you commit 'b' you get 10 years' c. If you commit 'c' (of the capital crime)you get death penalty ( in some countrys) , etc. etc,.
2. The second reason is simple because people don't like to know in advance but prefer to quess. If they are allowed to quess they will always quess in their own interest. So no wonder that every defence start with: "I had no idea that 'a' was not allowed'' or ''I had no idea what 'a' exactly means'',etc. This defence is based on the strange assumption that 'ignorance' is somehow identical with 'innocence'.
Now back to Goethe:
'it is allowed what you fancy, what is accomodating'
This is my transaltion. Well it may be the case that such longing is allowed by Goethe but there are many articles in the Criminal Law which don't allow us to do what we would like to do.
Regards,
|
Dear Lewm, Your comments say more about the design flaws of the LO-7D than about Lurne. I must plead ignorance concerning your Kenwood, just as you are ignorant concerning Audio Mecca, Goldmund direct drive and Lurne. Regards, |
Hi Folks
Halcro in your postings about the AT7V and the ATN155LC you asked about the reason for the differences between styli and the concomittant need for loading adjustments....
I've been thinking of writing a lot of this down.... an article for somewhere perhaps.
But taking a shot at it here and on the fly!
First the needles ability to follow the groove varies by shape and particularly by side radius... this will change the distortion levels (and some of that distortion may contribute to "enhancements" at certain frequencies)... but will not for the most part affect the fundamental "sound" of the stylus (in other words it affects fine details but not overall tone).
The cantilever is very much more critical: 1) it is the prime contributor to effective mass - and the lower the total effective mass, the better both tracking and high frequency becomes - this is however another "detail" aspect.
2) Mechanical Resonance and Damping thereof - this is the core and hub of the matter - the tone/sound of a stylus is fundamentally driven by this! The frequency response of the stylus will be altered by the resonance, and by the damping (and suspension - which is part of the damping) used. The Ortofon Ortophase article has graphs showing 4 different cantilever setups on an Ortofon MC200 cartridge - minimula/no damping through to heavily damped. This affects the amplitude frequency response as well as the phase frequency response substantially. Many of the cartridges regarded as "the best" have their resonances placed well outside the audio range (EPC100 well over 50kHz, Shure V15V 33kHz to 35k Hz)
Placing the resonance that high ensures that the stylus and cantilever can respond in a (relatively) pure linear way within the audio band... and a close to linear way well above the audio band.
Coming back to earth, and considering some styli I have measured....
The AT440MLa has a nice stylus and cantilever, but the mechanical resonance is spread from about 13kHz to 17kHz - the wide spread and "double peak" pattern of that resonance appears to indicate quite heavy use of damping... (internal to cantilever? - different materials in the suspension? not sure...) - Keep in mind that damping also does terrible things to phase linearity.... and these are difficult to measure or pin down subjectively...
So the ATN440MLa stylus has a tone which is driven by the raised area across the high frequencies - and the fact that this raised area is spread across a relatively wide frequency range.
Moving to the ATN15/20SS - with the beryllium cantilever... The mechanical resonance is just barely outside the audible area (21k to 23k) but the rise to that peak has an influence down to around 15kHz. because the peak is outside the audio area, it doesn't need to be damped so heavily - so the peak it much higher than the ATN440MLa peak, but its influence at 20kHz is only a touch more than the height of the ATN440MLa's peak - and by the time you get down to 16kHz the influence is negligible, where the ATN440MLa is at it's maximum influence around that frequency area.
The ATN15/20ss therefore sounds much more inherently neutral as a result (its midrange is well outside the influence of the resonance - where the ATN440Mla resonance influence extends down to 8kHz or perhaps even 5kHz)
3) Loading: given a rise at the extreme high end, on the ATN20ss stylus - Neutral results require a load that drops off in an inverse relationship to the rise, resulting in a relatively flat frequency response. - This drop off needs to start quite late - so low capacitance and inductance is important, and avoiding high R loads as these may raise the high end exacerbating the already raised fundamental cantilever performance.
By contrast the ATN440MLa needs to have a rolloff that starts earlier as its own peak starts earlier - so different capacitance - and a lower R loading to keep from adding a rise in those frequencies...
You can see that these two cantilevers will have very different "sounds" - their fundamental frequency response is very different - and therefore the right loading to provide a flat F/R is different - the loading must match the stylus - not the cartridge! (the cartridge is of course a factor)
Now the cartridge - in the past I have said the cartridge has the least impact - which I still hold to, but they are interesting beasts too... Cartridge electrical frequency response is NOT linear A cartridge is a coil/magnet system much like a transformer, and suffers from increasing inefficiency as frequency rises. The quality of the materials and construction will affect the level of inefficiency - as will voltage levels & frequencies involved.
What I am observing is that when looking closely at cartridge frequency response, all cartridges have a response peak in the lower mid/high bass region (between 150Hz and 300Hz) and then response shows a consistent downwards slope thereafter. The angle of that downwards slope is most likely related to the effectiveness/efficiency of the construction. This means that all magnetic cartridges tend to have a slight bass "hump" (the "warmth" of vinyl) and then a midrange slump. Many cartridges then use a combination of electrical and mechanical resonance to "fill out" that drop. (there is also a much more dramatic drop when the LCR response shoulder is reached...) The better the quality of construction/design, the lower the slope angle - and the less need there is to use resonances to fill things out. (and therefore top end cartridges tend to push the resonances further out... because they can!) You can easily plot the Inductance, Capacitance, Resistance frequency response of a cartridge, and then you can experiment with differing values of C & R which will show how the response can be tailored- high end can be raised or lowered, a peak can be induced, and the shoulder after which performance drops rapidly can be shifted back or forwards in frequency.
When you change styli - the cantilever F/R is different, and to balance it out, you then need to adjust the capacitance and resistance, to change the cartridge curve to properly match the cantilever curve and provide a "flat" frequency response..... so it is definitely stylus driven - not cartridge. Using a different model form the same manufacturer, or using a stylus from an after market manufacturer - regardless of its quality - will require a change to the loading.
Another example - a Shure M97xE will tend to sound best at 62k with its original stylus, but tends to sound best at 47k with the SAS N97xE stylus...
Other cartridge related thoughts: A cartridge is a self biasing environment - applying a voltage to the cartridge changes its frequency response (marginally but still changes!). There are some discussions on VE about the possibility of phono stages providing some biasing voltage... But the important thing to consider is that the signal produced - the music itself - is in fact a bias current, affecting the frequency response.
Keeping in mind that I am not a physicist or Electrical engineer.... but I believe that this biasing influence is non linear with voltage - that is to say, at lower voltages and inductances the influence of the sound may be proportionally reduced. The advantage of LO systems may in fact be the improved linearity due to reduced self biasing influence. This may also be one of the reasons why many of the higher quality styli have a lower output (along with having lighter magnets to reduce effective mass...). Lower inductances tend to push electrical resonances further up the frequency range (good!) - but may also be shifting to a range where self biasing is also reduced....
In any case - coming back to the point... yes - loading follows stylus... Switching AT cartridge bodies allows experiments with differing inductances and the same styli... the overall "sound" follows the stylus. Differences tend to be driven first by the stylus - then beyond that there are the differences driven by the various types of non-linearities and the effectiveness of the designs in coping with them - areas where some people may not even hear a difference.
bye for now
David |
Timeltel, you talked about analysing Square Waves in evaluating phono stages...
What tools did you use for the analysis?
Have you looked at similar analysis for cartridges?
This is one of the ways of looking at both impulse response and phase response... but it requires the right test track, and the right analytic software...
I do have at least one record with a square wave track - but need to find a way to analyse it!
thanks
David |
Hi Raul,
noted your comments about RIAA accuracy...
This brings to mind the question of what is the RIAA encoding accuracy of the standard lathes used for cutting the masters?
Not that there is justification for varying from the standard... and doing so involves every increasing risks (in terms of reproducing the recording).
But I do wonder, what are the RIAA margins of error in the mastering process, and therefore what is a reasonable margin of error to aim for in reproduction?
No point sweating over 0.0005% if the mastering error is within 2%... But if mastering error is within 0.001% then ideally you would want reproduction within the same order of magnitude or better!
bye for now
David |
Dlaloum,
Real food for thought. I'll be keeping abreast of associated developments.
Gratefully |
Regards, Dlaloum: Thanks, David, for your research into the relationship of cantilever resonance, damping, and the relationship to loading. Your easy to read style makes this understandable and takes away much of the mysticism many associate with cartridge design. The Tom(linson) Holman paper before the AES can be found (PDF) here: http://www.davidreaton.com/PDFs/Holman_AES_paper.pdfAdditional research is to be found in back issues of the Boston Audio Society. Thanks again. Peace, |
Thanks for that link Timeltel...
An excellent article - and valuable as much for its inherent content as for its references...
I need to try to track down Hallgren's "RLT" parameter - I have been kludging this in my model, but if that reference leads me to something a bit more scientific than my approach that would be great!
Right now I measure the loss slope with excel apply it back as an adjustment factor to the cartridge model - once done for a cartridge, it improves the accuracy of the model across all the possible loadings for that cartridge markedly. (makes it much easier to decide on an optimal loading - and to reduce the number of options that get listened to)
Some of the stuff in there is a bit too technical for me (like I said - I'm not an EE!) - but I get the impression that in the discussion of cartridge/phono stage interaction, there is also the possibility of certain loads (too high? too low?) causing additional distortion and non-linearity...
This is a factor I have never considered! Is this common? - Quite a few of you are designing and building your own phono stages - is this a concern, and should this be considered when choosing the load for a cartridge? - Or is this in fact something which post this article and ongoing developments became merely a footnote in history, not a concern for phono stages post 1980 (?).
In any case an excellent article covering a lot of the limitations and inter-related variables of cartridges... good stuff!
bye for now
David |
Hi David, Square wave response was shown to me by an electronics designer. The output of the device was plugged into a scope and analyzed. In the case of an amplifier a signal generator can be used as the input. In the old days square wave response was sometimes published for carts. The pictures were like those on a scope. Perhaps there are oscilloscope programs for PC?
Again, I would quibble about high frequency resonance figures but it would be prudent to wait till controls are in place. I realize your comparison was "off the top" but I believe the compliance is much lower on the 7V and every aspect of stylus and cantilever is apples to oranges to the 155LC. I also wonder about damping and the 440. I believe it might be something other than damping. The 440 sounds "right" with a beryllium cantilever and a ML tip with "standard" loading. Compliance is even higher with a 152ML, but damping goes with the stylus. It's interesting to speculate. Regards, |
Dear Fleib, You are quite correct, I am ignorant of the 3 turntables you mentioned, but I only commented on one model of one of those 3 brands that I listened to at least 15-20 years ago. I listened long enough and often enough to that one particular Lurne' turntable to form an opinion. If you noticed, I tried to allow for the probable fact that his products have favorably evolved since then. The earliest efforts of any designer are often best forgotten. Sorry if I offended you.
Having owned two belt-drive turntables with relatively undamped spring suspensions (Thorens TD-125 and early SOTA Star Sapphire III), I feel I can fairly say that they are not to my taste. |
Dear Lewm, No offense taken. I think it's unfair to Lurne. A Goldmund direct drive was my all time favorite table. I wish I still had it. It left my LP-12 in the dust. Now I have a Sapphire sitting on the floor disassembled. It awaits my redesign with a Teres rim drive motor. I can't listen to most heavy plattered belt drive tables. Whatever floats your boat and belt drive tends to sink. Regards, |
Dialoum, while I appreciate your research and descriptions, you make one assumption that I wonder about -
"The mechanical resonance is just barely outside the audible area (21k to 23k) "
I realize the 20K audible area is a long-standing assumption, but there has been quite a bit of research in the past few decades that challenges the perspective of high frequency perception. James Boyk was a professor at Cal Tech, audio reviewer, and a concert pianist. He has written articles on research that identifies perception of musical tones well above 20K.
http://www.cco.caltech.edu/~boyk/spectra/spectra.htm
This is offered not to diminish your findings but to suggest a revised consideration for cause and effect. |
Dear Nandric, ...;-) ... "it is allowed what you fancy, what is accommodating" ...a good translation, if however Goethe's "was sich geziemt" includes not just what is accommodating, but what is legal, commonly accepted and ethically approved as well. So the smart spirit of the 18th century took the safe road home in this phrase. It goes in a different direction compared to Friedrich's "Ein Jeder werde selig nach seiner Facon". Cheers, D. |
Dear Fleib, I don't know whether the word "fair" applies. I just gave my opinion and qualified it so as not to include his more recent designs. For example, it would not be unfair for you to say I am balding. I tried to be fair, in fact, in the sense that I concede that what I heard so long ago may be totally irrelevant to Lurne's present work. Now, how are you going to mate the Teres rim drive to the Sota? Won't the Sota chassis get in the way? I once thought of using the Teres with my Nottingham Hyperspace, because that one has no interfering platform or apron that would impede contact between Teres and platter. |
Lew, here's a thought. An audio buddy bought a Teres rim-drive motor and controller to try with his Scout. It produced a wonderful (fill in audio adjectives here) improvement over the stock belt drive. That experience encouraged him to try DD so he then progressed though a Kenwood 650, then a Luxman 4xx, each time hearing small but worthwhile improvements.
Most recently he found a belt drive Micro Seiki table (exterior motor, not sure of model #) but was having problems with accurate speed. On an inspiration he set up the Teres in place of the MS motor, using some specialized cord drive rather than direct rim contact. With the Teres motor/controller he was able to achieve correct speed, and what he believes to be the best vinyl playback he ever experienced. For the curious this set up includes a new Ortofon arm, Oyaide headshell, and Dynavector XX-2. |
Hi Fleib,
with regards to damping, the type of damping I am talking about is within the stylus mount - direct cantilever damping, as opposed to cartridge body damping...
Which means that when you exchange styli on you AT440MLa to a beryllium ML tip (155LC? 152?) you are changing the cantilever damping as well... - and of course the compliance is another cantilever suspension parameter - so placing an AT-7V stylus on an AT440MLa would obviouly give the AT440MLa the compliance of the AT-7V.
With regards to square waves, I was hoping to find some software suggestions that would analyse the square wave by FFT, breaking it down into its component parts to allow identification of its component parts... ie: rather than looking at the square wave on an oscilloscope (I have software oscilloscopes), come back with data on that square wave in terms of phase/frequency, rise time/slew rate and distortion...
Hi Pryso,
thank you for that link - an interesting article- particularly the part about the saccule. It is clear that the presence of ultrasonic sound can be perceived.
What is not clear and is hotly debated is to what degree the perception of that ultrasonic sound is direct perception of the utrasonics themselves, or indirect perception of the intermodulation artifacts of the ultrasonics which are in turn within the audible range.
Several other problems exist too - Ultrasonics are incredibly "beamy" the beam from an ultrasonic tweeter is incredibly narrow - and the appropriate "sweet spot" is therefore very narrow too. Reproduction and effective use in a stereo (if warranted which is by no means certain!) - is problematic. (although there have been experiments in it)
The commonly accepted approach to ultrasonics (which various research groups are researching... and may in due course change) is that 1) there is definitely ultrasonic components to many many instruments, 2) These are (primarily?) perceived through the intermodulation of these frequencies with other frequencies present at the time of recording, producing IM that is within the audible range, 3) Reproducing the original ultrasonics in a stereo system is doubly problematic as it invites a secondary IM of the recorded ultrasonics with the reproduced music - the resulting IM being another form of distortion.
Further problems exist! - An analysis of many different forms of amplifiers, recorders, and other electronic equipment used in the audio chain, will frequently show ultrasonic distortion or simply RF pickup of various forms - even when nothing is being played back. The recording/playback chain is not usually designed to cater to ultrasound, and therefore this range is not kept "clean" and "noise free" - hence there is frequent use of HF filtering to clean up the "grunge" - which otherwise can affect the primary audio signal through IM (within the electronics).
Personally I know that with my own recordings, an analysis of the frequencies above 20kHz always shows the system picking up various signals that are clearly not related the recording (I can unplug the input and they are still there!) - their levels are lowish (below -60db) but would be considered unacceptable within the audio range. The signals vary by time of day, and perhaps other conditions ie: it is not clear whether they are products of radio interference or carried by the powerline (even though I run power fitering) I get better results in an audible sense, by filtering above 20kHz - which I do in the digital domain, after recording.... but I believe another level of improvement is possible by moving the filtering to prior to the ADC, and therefore taking a part of the spectrum away from the ADC to facilitate more accurate reproduction of the audio spectrum, (this would need to be done keeping in mind phase issues - so a gentle slope analogue filter?)
An interesting topic.... LP's can certainly have signals well beyond 20kHz, and a well pressed LP can have reasonable level material through to 50kHz without a problem. But whether the material above 20kHz SHOULD be reproduced is quite a different question - and the reproductive tools we have available - the entire chain in point of fact- is designed only for and around the audio range. Although some components have extended frequency response, this is usually claimed and published as a means of demonstrating that the more limited audio range is therefore clean and linear as the device can perform well outside that range. We have not even discussed the limitations in the vast majority of microphones...
bye for now
David |