Henry, At the risk of beating a dead horse and mixing metaphors (because the horse has left the barn), have you ever seen the finish on the Saskia and other turntables made and sold by Mosin (Win Tinnon)? He (and OMA, as well) obtain a beautiful smooth black finish on slate by means of treating the material with certain finishes. Also, they start with Pennsylvania slate, which has a unique near-black color to begin with. I borrowed Mosin's ideas in finishing off my own slate plinths (made for Lenco, Denon DP80, and SP10 Mk3).
Nude Turntable Project
I could not fit the whole story in this Forum so have had to add it to my System Page.
I am attempting to hear if a 'naked' DD turntable can sound as good as Raul claims.
Please click the link below to read the story.
NUDE TT81
I am attempting to hear if a 'naked' DD turntable can sound as good as Raul claims.
Please click the link below to read the story.
NUDE TT81
481 responses Add your response
@Mr P- There are, "metallic" Corian colors available, that(in order to be, "metallics) contain aluminum flakes. No other Corian contains aluminum(or any other metal). I've been using Corian for a couple decades and there is no resonance or ringing, at all. Regardless of how it's suspended/mounted, however one attempts to get it to ring or resonate, it will not. It's dead within the audio spectrum. If struck; One thud will be all you'll get. Free samples are readily available from distributors, that the OP can experiment with. |
Henry, thanks for continuing to update us with your trials. Material choice can be tricky and I believe there are some misconceptions about benefits. Years ago I read advice to try a marble cutting board for placement under a turntable. I'm not sure how marble measures up against granite but when I checked out the recommended marble I found a knuckle rap produced an audible reaction, almost a ringing. I've read that Corian includes chips of aluminum and it too can ring, pitch being dependent on how much aluminum. Brass of course is also utilized to produce church and tower bells so I think shape and thickness must be critical there too. I've also read that slate, being a sedimentary material, is actually layered so good at dissipating energy, whereas stones such as granite and marble, being more solid, do not reduce energy as well but simply transfer it. They may not be as dense but I go back to thinking of certain hardwoods which have been traditionally selected in instrument making. At least their energy transfer (vibrations) are sympathetic with musical tones. |
Just thought I'd mention Dupont Corian, as an excellent, easy to work, non-resonant, very dense material, that can be built up into whatever thickness desired: (http://casf.com.au/?src=globalnav) I've personally used it in a variety of resonance defeating projects, with great success. I like granite too, but Corian can be worked like wood, machined like aluminum, comes in a wide variety of colors and takes a very glossy polish. |
Granite certainly has a sound to it.I hope not in this situation....? As I'm only using the granite to create a 'mass cradle' in lieu of my stainless steel cradle, I'm hoping for no contribution to the sound of the turntable itself. After all....when I went from the 'nude' table on tiptoes to sitting in the steel cradle, there was no alteration to the tonal characteristics of the table. In other words....the steel cradle had no 'sound' to it so I'm hoping the granite table similarly has no sound to it...🙏 We'll soon know...🕟 |
Is it time for some clothes.....👀👗❓ Five years ago I went nude...but don't tell my kids... Three years ago I went nuder...kind of 'Punk Mad Max'.... Sound was good. Inspired some fellow converts and adherents but a small problem arose. Whilst my solid cast bronze armpods at 25lbs each would never move......the rather lightweight cradle could often be nudged in the process of cartridge swapping and the spikes could slide along the hard laminate on the cantilevered wall shelf..😩 Tired of re-checking the alignments of three arms, I decided to drill through the laminate at the positions of the three spikes to prevent any further sliding. Mission accomplished but small problem now became BIG problem..💀 The tips of the spikes now made contact with the shelf substrate and its inherent stresses. These subsonic tensile stresses now induced a resonant frequency response in the stainless steel cradle which transferred to the platter/record interface and could be amplified by the stationary stylus at maximum volume settings. Most turntable designs deal with structure-borne feedback in a combination of various methods with mixed results. Suspending the plinth on springs or trying to isolate it with rubber or other compliant feet or various types of air-inflated supports is one method. Mass is another. Real mass is still another... I have chosen to try a 'mass' solution...🐘 The idea behind the 'mass' approach is the hope that physical vibrations can be absorbed and dissipated as heat within the plinth/platter instead of allowing resonant response characteristics. Sometimes this works and sometimes not.... With the space restrictions of my 'nude' setup I can only create a cylinder of either granite or gunmetal/bronze (wood is simply not massive enough in this small structure). Bronze would weigh 3 times more than granite (19Kg vs 7Kg) but also costs 3 times more...💲 So at this time....somewhere in China, there is a CNC machine routing and polishing my turntable 'plinth' cylinder out of a solid block of black granite..😊 Gosh I hope it works..... |
Halcro - steamed with ginger and shallots. Sounds delicious Henry. The authentic Canadian recipe is a shore lunch and it includes a small fire next to the water, beer mixed with specially seasoned flour in a pan. Nice fish Dover. sounds like a great time was had by all. Dover - Are you sure that trout is not fake, there are a lot around... I now await to hear about your next adventure Dover - We have heard many mystical stories here about the great white's downunder. Have you ever fished for one? I agree we do need to be careful of fake fish. |
Ct0517 09-27-13: Ct0517Are you sure that trout is not fake, there are a lot around... Meanwhile this from my last visit to the deep south (latitude 46 degrees), no dover sole there, but enough kai moana to keep the whanau replete. One of several..... Fishing for the Iwi Savoured whilst listening to Schuberts Trout Quintet - Schiff/Hagen Quartet on Decca. Well seasoned & accompanied by Rudi Bauer's excellent Quartz Reef Central Otago Pinot Gris. |
Hi Henry I am now going fishing Henry. I will be using a Cordell CC Shad Green/Yellow to see if I can snag a lake trout This pic is only a few days old The hit was real. The fight with 4lb pound line was real. The landing and pics are real. The emotional rush of - letting it go - was real. Music gives me a similar rush. corny ? yah... but true. Not a laker but only the 4th rainbow trout ever caught in this lake - must have come in as a baby from a smaller feeder lake. another thought on the Verdier Due to its low power requirements I intend to hook it up to my electric trolling motor battery once fishing season ends. This way it gets used year round. I mean the battery not the TT. :^) The new speaker project may delay things a bit but it will get done. Continue to inspire. Cheers |
Dover, Whom are you addressing? If you are addressing me, then I was only referencing the definition of "nude" back to the beginning of this thread, whether you like the idea of nudity or not, in a turntable. Please recall that I was not a proponent of the approach at all, and still I am not. I agree that the definition has blurred in the course of 8 pages of posts. Over about the last 25 years, a trend in the design of belt-drive turntables developed according to which the platter is mounted on a cylindrical plinth that is of about the same diameter as the platter, such that there is no rectangular "deck" area in the plane of the platter. Rather, the tonearm(s) are mounted outboard via structurally rigid supports that are anchored firmly to the heavy cylindrical plinth structure. It was my empirical observation that this idea is a good one. However, it is far from consonant with the concept of the "nude" turntable, set forth on page 1 of this thread. Actually, you and I do not disagree. I can live without the lectures. Thanks. |
I am very reluctant to say this or whatever in the presence of Lew and Dover who are known as critical minds. In particular regarding the opinions of others. But if I remember well (not easy at my age) by the first DD TT's this, uh, 'magnetic matter' was immediately mentioned with warning for the use of the MC carts in conjunction with them. One of the reasons for me , except being the best TT ever, to buy the LP-12 then. Strange that after so many years this 'magnetic matter' is again reinvented or rather re-introduced. Regards, |
09-21-13: Lewm Of course with the "nude" approach, the shelf is the plinth, as both the TT and armpod are coupled to it, unless the feet are levitating, or you are reinventing the English language. Furthermore Halcro's Victor motor & platter are bolted to a flimsy chassis adorned with copious electronic boards and transformers, which, in turn are attached to the new stainless steel frame. One could argue that the flimsy chassis or the chassis and frame is the plinth in this instance. Ironically the Verdier ( and Micro's,Melco's & Final Audio) are more naked than the pseudo nude Victor because they are not mounted in a flimsy chassis and are not adorned with electronics and other unnecessary paraphernalia. Therefore I suggest you have misappropriated the use of the word "nude", and should find a more appropriate word to describe the not so nude Victor. |
The Verdier is NOT "nude" by the original definition put forth by Halcro after Raul. (Please go back to the beginning of this thread.) Nude means or is a synonym for "no plinth". No plinth means that those who adopted the approach mounted their tt chassis' on "feet", most typically the AT616 feet, with no physical union except gravity between feet and chassis. The Verdier has a plinth of the kind commonly used for many BD turntables, e.g., most of the Nottinghams, the Galibier, Redpoint, Teres group, Simon Yorke, etc, etc. I doubt that the makers of those other BD tt's would call their products nude by that definition. But you can call it what you want; just change the dictionary. |
Hi Chris, Hi Henry there is no wood here. As you are genuinely interested please find attached some email answers in my direct correspondence with Mr. Verdier. Your question is answered below. I also have updated pics in my virtual page that show the setup clearly. Imo - Mr Verdier is genuine; but understand he is also a manufacturer with a business to run. This is very evident in how he addresses my setup ball questions. My vintage granito model never came with one. His email answers are un-modified. I am now going fishing Henry. I will be using a Cordell CC Shad Green/Yellow to see if I can snag a lake trout. Cheers --------------------------------------------------------------------------------------------------------------------- Dear , Thank you for your message. A gap of 1cm is absolutely normal. Can you tell me more about your curious tone arm? Please accept my best regards. J.C.VERDIER Dear Many thanks for the compliments you send me. Thanks for the photos where I can see in what high quality of environment my turntable is installed. For sure your pleasure is my pleasure and we share it with numerous users of my material. Please accept my very best regards. J.C.VERDIER Dear , Many thanks for your message. Your base is made of GRANITO . Granito is a material composed by little pieces of marble becoming from different origin agglomerated inside a mold with cement. And of course machined and polished to obtain a good looking. The resonance of the plinth with its suspension is about 5Hz and it is well absorbed by the air cavities. Please accept my best regards. J.C.VERDIER Dear , The arm board is made of 2 different aluminum parts: a cubic part and a plate . Hopping that you enjoy the listening of good records. Please accept my best regards. J.C.VERDIER Dear , It is not easy for me to choose what is better for you. So I will tell you another time what is told. The possible installation of the ball was poposed to answer some customers who want to try to use the ball. At the beginning it was only optional . But later , to normalized the manufacturing , I included systematically the kit steel ball + ceramic past. For my part I am not in favour of using the ball in accordance with the original design . Probably you have this original design so you don't have the steel ball. Don't worry about the stories of pirates , for sure some of them tried to attract customers by copies , because they are not able to conceive a product by themselves . I don't have any of them in hands and I have no comment on their working. For sure that should be easy if only a steel ball could let a turntable work properly! Have a good day and enjoy your records . Please accept my best regards. J.C.VERDIER Dear Your 1Kg center weight clamp does not ask problems. We could put till about 7Kg on the Platine Verdier before the magnets can't sustain the platter. Please accept my best regards. J.C.VERDIER |
Hi Chris, The Verdier has always interested me....and as you say......Nude....but also Copernican in concept? One question I have.........what is the material of the tonearm mounting pods? They look like wood? And how are they fixed to the base? And how do you organise a different one when you get a different tonearm? |
Ct0517 09-19-13: Ct0517Thought you might like to have a look at a Verdier on the official Verdier website with the thrust pad and ball option. http://jcverdier.me.pagesperso-orange.fr/nouvellepage2.htm It is not a fake. It doesn't oscillate. JC Verdier does know what he is doing. Fyi Callas also do an upgrade kit for the Verdier to enable the adjustment of the ball precisely such that the platter is mechanically grounded, as per the Goldmund philosophy, but the weight borne is very very tiny, just enough to ground the platter. Many folk prefer the sound of the Verdier with the platter mechanically grounded to dissipate energy, and with a decent aftermarket motor and power supply to improve the speed accuracy and timing. Naturally there will be other folk who prefer the more mellifluous and less precise sound of the Verdier with standard motor and non grounded bearing. |
09-19-13: Ct0517The origins of the term ground zero began with the Manhattan Project and the bombing of Japan. The Strategic Bombing Survey of the atomic attacks, released in June 1946, used the term liberally, defining it as: "For convenience, the term 'ground zero' will be used to designate the point on the ground directly beneath the point of detonation, or 'air zero.' William Laurence, an embedded reporter with the Manhattan Project, reported that "Zero" was "the code name given to the spot chosen for the atomic bomb test" in 1945. This forum is a sharing and examination of ideas, not a war zone. The use of the term Ground Zero is perhaps unfortunate. |
Lewm - I'm sure it does; I've never seen the thread slip on any of those. That was part of my point to Dover. I thought also you were going to take issue with his idea that the Verdier needs a "stronger" motor. To my way of thinking, the Verdier is one of those in the "hi mass/lo torque" grouping of belt-drive turntables, a grouping that I regard highly for sonics and which includes the Walker Proscenium. Lewm - as far as I can tell from pics of the Final TT - both the Final and Platone Verdier use thread but similarities end there. they are totally different executions - as different as an ESL and Dynamic Cone speaker. I am sure Dover will enlighten us more about his Final TT. The Verdier is outside of the box as you can see from your dealers setup. It is like your childhood merry-go-round. Both the Platine Verdier and merry-go-round, once spinning need only occasional jolts / pulls from the motor/person to keep them going. The motor can be seen cycling on and off. If setup properly you can in fact turn the motor off and on for a short period and not notice the pitch change. Try that with your Dealers TT - I am very curious what you will hear. Whatever one might think of the Verdier, I believe it was designed "as a whole", and the use of a relatively weak motor is intentional. You are absolutely correct and the Verdier is not for everyone. But here is an most important consideration. We all hear about how powerful this or that one TT is; how torquey it is. The big motor. How quickly it gets to speed. Well I used to race on land, water and snow. if you ask any veteran racer - you have a race to run - you must stay at a constant speed and there are alot of turns peaks and valleys on the race course. The first half of the race will be easier to navigate over while the last few turns will be tighter. The magic question. if you had to choose -do you want better torque or brakes based on these conditions ? The drivers/riders I knew including me would say that braking is more important. Now with a TT both are important but ask yourself how does your TT brake? Is there a motor involved, a brake pad that moves in and out. Does it need to attach to a spindle, belt or thread to have the ability to brake. Well the Verdier uses no motor for breaking. Braking is done with the replusive force of the magnets. It is natural physics dealing with the record behavior. Am not aware of any other TT like this plus it has no thrust bearing. If you cut the thread while it is turning the platter turns for about 1/3 the time than when turning as a whole system connected to the motor pulley and just turning the motor off. Also in keeping with Henry's Nudie thread the Verdier is as nude as you can be imo. This design also however leaves it open to audiophiles mods. The motor can be replaced with anything along with any kind of belt or thread. Once you replace the original motor and thread system you have defeated JC Verdier's well thought out design. Your dealing with a platter system that has braking action in it for a reason. Your on your own. What other TT motors have been built to work with this type of platter system. Hey - who am I to stop someone from putting on a TW motor, or a VPI one or lets see how about a Galibier one. Heres a good one. An sp10mkii set up beside with a special acrylic platter set at the right height so thread can be installed. hows that idea ? it comes from another Verdier owner. As long as you're happy I guess. Crazy hobby. Cheers |
09-19-13: Ct0517Your recollection is not correct. I have not used the words "set up bearing" and "oscillated" in the context of the Verdier. I have not heard a "fake" Verdier whatever that is.Doverimo - if you truly understood how this table worked you would not have made this comment. I guess JC Verdier does not know what he is doing. If I recall you discussed a Verdier in the past on this forum and it required the use of a setup bearing to run properly as it oscillated. Could it have been one of the many counterfeit ones around ? Its a very imitated and duplicated table. You need to be very careful. I understand perfectly how the Verdier works, and there have been many iterations since the first Granito based one came out.. Suggest you read up on the Verdier. http://www.jcverdier.com/ADSL/platineV.html Hifi News Review - "Incidentally, the bearing tan be fitted with a bail and thrust plate, by-passing the magnetic support. but apparently it doesn't then sound as good."You might also like to check out Dertonams comments as suggested regarding the use of a ball : 04-01-09: Dertonarm With regard to my comments on weak motor, the Final Audio can pull the 22kg platter/mat/clamp to speed in less than 1 revolution. The Verdiers that I have seen and heard do not have this drive power. I know a couple of Verdier owners who have replaced the motor drive to good effect. The Final also has a correctly designed pulley for thread drive with self centering profile. The original Verdier came with the option of a belt or linen thread ( or nylon according to one review on the Verdier website ). The optimum pulley profile for a thread drive is a concave face so that the thread self centres. Running a thread on a pulley with a flat face can result in instability of the thread tracking as it can ride up and down, or will find a natural position either at the top or bottom of the pulley, depending on how accurate the pulley is in terms of congruency to the platter edge. 09-19-13: LewmTension and a correctly design pulley ensures that thread remains stable as above. |
Lew The shielding on the L07d looks like galvanized steel sheet. I think that it improves with the addition of extra shielding because there are some gaps and that in this case more is better. Yes it does resemble a flying saucer in profile and is , almost, completely encapsulated in shielding. Another interesting design is that extensive shielding is used below the motor. Btw it is not my intention to criticize the design. It is simply a different approach to building a motor. I very much like its speed sensor approach and the clever way the main rotor magnet relieves some of the platter weight from the thrust bearing. |
I'm sure it does; I've never seen the thread slip on any of those. That was part of my point to Dover. I thought also you were going to take issue with his idea that the Verdier needs a "stronger" motor. To my way of thinking, the Verdier is one of those in the "hi mass/lo torque" grouping of belt-drive turntables, a grouping that I regard highly for sonics and which includes the Walker Proscenium. Whatever one might think of the Verdier, I believe it was designed "as a whole", and the use of a relatively weak motor is intentional. (Actually, isn't the Final Audio Parthenon also in this group? Maybe it has a high-torque motor. It sure has a high mass platter.) |
Lewm - I've often wondered how the heck they can keep the thread from slipping down the smooth sides of the platter. Lewm - Depending on my mood I do one of two things before a listening session in front of the Verdier. I dance a little dance or I get down on my knees and recite a short prayer in front of it. So far the same piece of silk thread has been on their 9 months. It must be working. cheers |
Dover - imo each of us needs and has a reference point, a ground zero for this hobby and other things in life. Without this anchor we become lost. This ground zero is a little different for everyone. For this reproduced in my room as far as source goes - my Studer deck playing 15 ips tapes is it for me. here's why. Before my Studer tech gave me back my tape machine he put on a tape that had different frequency notes on it. He played each of them for one minute. It was rock solid in pitch. Never wavering. I wont get into its sonics here. imo - a TT setup can come close, but will never be this good because other than all the many electro/mechanical "items" that need to be set up with the table, tonearm and cartridge - the record itself is so so flawed. oh you can try to setup things as best as possible for one record. But the next one will be different. I have hundreds in rows next to my listening chair that I randomly select from. What are you going to do. So the record for the vinyl hobby imo is the Elephant in the Room. Everyone loves to talk about their shiny TTs, tonearms and cartridges - the equipment. No one wants to talk about the source. Sorry for ranting on your thread Henry.
imo - if you truly understood how this table worked you would not have made this comment. I guess JC Verdier does not know what he is doing. If I recall you discussed a Verdier in the past on this forum and it required the use of a setup bearing to run properly as it oscillated. Could it have been one of the many counterfeit ones around ? Its a very imitated and duplicated table. You need to be very careful. fwiw - I remember reading Syntax timeline testing the vintage Verdier - it was on the pass list. Cant remember the thread. My Verdier and my other hobby tables are compared against my Studer in my own room real time - switching between the two. So thats my Ground Zero Dover. Whats yours ? |
Dover, Funny you say that about "converting" the Verdier to thread drive. Nearly all, if not actually all, the Verdiers I have ever seen have been using thread drive. I actually thought it was "stock". One well known emporium near me that sells Verdier places the motor about 3 feet away from the platter and uses a thread drive. I've often wondered how the heck they can keep the thread from slipping down the smooth sides of the platter. Richard, You voiced my own thoughts on the pitfall of a coreless motor; the orientation of the magnet and coils is at 90 degrees to that of a conventional motor, and this would result in max field strength in the vertical direction. Plus, the coreless motor is very close to the underside of the platter, much closer to the platter than a conventional motor in a Technics or other similar DD. I've noted that the L07D motor is a completely discrete unit, sealed in a casing shaped like a movie version of a flying saucer. Do you think the casing is made of mu metal or something with similar shielding properties? If so, why do we perceive that adding another shield under the platter mat makes a further improvement? |
I just downloaded the Teslameter 11th App onto my iPhone and it's very interesting. It measures an electro-magnetic field in either Micro Teslas or Milli-Gauss (1 Tesla=10,000Gauss). Just sitting in my listening chair gives a reading of 43uT or 590mG whilst at the turntable platter I can get a reading from 92-over 200(cut-out point) uT or 590-over 2000mG. Readings UNDER the naked TT-101 are all over the 200uT max limit. The readings change with power on or off so a complex study is required. Because of my 3 tonearms.....the position of each cartridge traverses a different path with the cartridge passing over the transformer reading the highest. Of course...all the cartridges at their inner-groove points are directly over the motor coils and the reading goes off the chart in all these cases. The interesting thing is no difference in sound is heard by me as each cartridge passes over different reading points...and the arm passing over the transformer sounds no different to the other arms in intrinsic quality. As a side-note....in this months issue of Stereophile with the 2013 Recommended Components.....for turntables ranked A+ and A.......76% have their motors mounted in the plinth close to the platter. If Thuchan can download this App to his iPhone and demonstrate that the EMT 927 provides plenty of magnetism.......it may be possible to make a case for the beneficial effects of this ingredient? :-) |
09-19-13: Ct0517I agree, it is folly to convert a belt drive to thread drive, unless all the engineering principles on motor selection, pulley design and platter/bearing design have been revisited and are clearly understood. For example, the optimum pulley for a thread drive will have quite a different profile than that of a belt, as well as the motor design, power delivery and platter mass. An example of this is the Verdier, where the motor is not strong, and addressing this should be a prerequisite before converting to thread drive. It is quite an ask to go from tinkering around with DD turntables to designing a thread drive. A thorough understanding of engineering principles would be a prerequisite. I would recommend you search on Dertonams posts on thread drive in this forum for authoritative and informed analysis of thread drive principles. Dertonam has had a wealth of experience with the Micro Seiki thread drive TTs that were designed specifically for thread drive from the outset, as is the Final Audio Parthenon thread drive TT. |
09-18-13: Ct0517Ct0517 - your comments are incorrect. Though I own a Dynavector arm I have not used it for a long time. It is handily outclassed by my Fidelity FR64S, Naim Aro and Eminent Technology ET2 arms. Please refer to my post in your ET2 thread... 05-16-13: Dover Another correction: Very minimal magnetic damping is used on my ET2, none on the Denon 103 set up, and it is well away from the cartridge and cable. This too was explained in your ET2 thread. 03-03-13: Dover |
Chris, the increase in flux strength on the SP10 MK2 when stopped is due to the brake solenoid. Powered at stop, off when running. two comments Richard 1) You confirmed that this app on my phone actually works. this is kind of cool. 2) I'm impressed with your findings. I currently have an L07d in a thousand pieces. I look forward to reading about how you fit an ET2 on that. :^) But Boy, would I really like for someone like you to get yours hands on a thread drive design TT - NOT - a belt drive design that has been converted to thread. I would love to read your impressions ... Cheers |
I currently have a L07d in a thousand pieces. It uses extensive complex shielding around the motors many parts. Quite necessary I think, since the coils are close to the upper platter surface and are oriented vertically, focusing their flux up and down as opposed to horizontally on some other designs. Chris, the increase in flux strength on the SP10 MK2 when stopped is due to the brake solenoid. Powered at stop, off when running. I don't bother with the brake at all, using the EM braking of the motor itself to pull down the platters speed at stop. |
Stick your detector down there, and see what that does. Also, the thick platter gives distance from any possible problem up on the platter surface. Hi Lewm I fear for the life of my 2 year old Samsung Galaxy if I stuck it in there. a little curious but not that much..... My daughter just expensed a new IPhone to me and my son a Samsung Note. They both turn 19 on Friday this week - how could I refuse. My phone now needs to last a couple more years. btw - Drinking age in Ontario is 19 - maybe they will buy me a bottle of wine in return. I suspect any levels I measured came from the cartridge - I was only six inches away from it. I am however surprised at Dovers comment. I dont think it is ideal to have electromagnetic fields floating around the cartridge, irrespective of what type of TT is used. I mean considering he uses a Dynavector tonearm and preferred ET2 Magnetic damping. :^) Cheers |
Henry, Don't own a Garrard 301. Do own a highly modified Lenco L75. In fact the only parts from a stock Lenco that I use are the motor, the idler arm and wheel, and the platter. Where there is a motor, there is an electromagnetic field. Thus I am sure that one would be detected with a detector in the vicinity of the motor. However, I use the PTP plate, which is 4mm of solid steel between the motor and the underside of the platter. Moreover, there is about 2 to 3 inches of space between the motor and the platter, and the platter itself is heavy aluminum. So, the shielding is at least "pretty good", and the physical distance would help as well. These fields generally fall off in accordance with an inverse square law; the strength is inversely proportional to the square of the distance. In DD's with coreless motors, like the TT101 and the L07D, the potentially radiating elements of the motor are particularly up close to the platter. |
I'm wondering if Idlers exhibit the same 'magnetic' characteristics as DDs seeing how they also have motors etc under the platter? I suspect that the EMT 927 would react "positive' to a magnet wandering amongst its innards.......especially with its steel supporting frame? Are you able to confirm this for us Thuchan? And Lew.....perhaps you could do likewise with your Garrard 301? |
Excellent Design? Of course :-) But, my personal Favorite is Audiophile Rule No. 2 "when it sounds good to you, it IS good" |
Lewm, I use the acronym above EMF to mean Electromagnetic Field. This will have an electrical component, measured in volts, and a magnetic component, measured in mG (milliGauss). The tester I used measures the magnetic component of an electromagnetic field in milliGauss. With regard to the Q on DD's, I dont think it is ideal to have electromagnetic fields floating around the cartridge, irrespective of what type of TT is used. Halcro, Yes I got the pigskin. If I can get some from the local abattoir I'll try it over the preamp. Do you know if it is from an Australian Yorkshire or a Japanese Landrace ? |
Dover, Did you mean "EMF" or "EMI"? The discussion has gotten a bit confusing with the interchangeable use of the terms "EMI", "magnetism or magnetics", and "electromagnetics". Different manifestations of the same phenomena but with different consequences. I think of "EMF" as "electromotive force" = Volts. Units would not be "Gauss", I don't think. Of course you would measure no EMI (or EMF) near the chassis of your belt-drive, where the motor is way outboard on the other end of the long belt. That is to be expected. Do you think the magnetic field or the EMI measurable in the vicinity of the platter of some DD turntables is damns them all, as a class? I am not even sure there is any consequence to it, and if there is, many have shown that the fields can be shielded. Halcro, I have no bone to pick with Syntax, but I agree on the observation that he and a few others who are countrymen to Thomas Woschnick do seem to revile his Raven turntables to an inordinately passionate degree. It seems strange at times. He did not insult the TT101 so much as he did insult the Raven. Did TW kick someone's dog? |
I received a sheet of mu-metal magnetic shield today and installed it in my TT-101. Here is the Before image showing the interior damped with automobile damping sheets. Here is the After image showing the mu-metal sheet cut into shape and placed over the motor. It is not grounded, nor is the turntable. The result is that the magnetic field has moved away from the tonearm arc area of the platter over to the opposite (left) side of the platter. It is also more intense on the left side than it used to be on the right side but I think that it doesnt matter because it doesnt reach the cartridge. Mu-metal can only shield an area from magnetism, it cannot destroy the field. It is like squeezing a balloon the air just moves to a different area in the balloon. Soundwise, I havent done any blind testing or even playing an album side with it and then playing the same side without it which is how I like to do it. But, I did play a few cuts on a few favorite albums and was (perhaps deluded into) hearing a better audio image and clearer notes and lyrics than I expected. I got that dumb grin on my face that I get when my rig sounds great. An easy tweek that I (almost for sure) believe in. Gary |