I'm not sweating it. Just responding to a previous post that suggests the video shows the transrotor as being seriously deficient in speed regulation. I didnt get that from the video, but if others can point out how to get to that conclusion, I am all ears.
361 responses Add your response
FWIW, I use a "Jeremy" bearing on my Lenco. Jeremy is in England and makes several different versions of replacement bearings for Lenco and possibly for Garrard. I have his "Superbearing" with an accessory clamp that attaches underneath the turntable chassis to keep a firm grip on the bearing housing. The whole assembly really works. Note, I have not compared the Superbearing to any other aftermarket bearing, just to the stock Lenco bearing assembly. Manitunc, Don't sweat it. |
to me, it looks like the Fat Bob is running very slightly fast, as the line moves very slowly to the right on each revolution. When the stylus drag is applied, the line quickly moved to the left, indicating a slowing of speed, and then stayed there, indicating a constant 33.33 rpm under load. the video didnt stay on long enough to see if that changed, but to me, it reflected a design which rendered the proper speed under load. Is something wrong with that? disclosure. I own a Transrotor Fat Bob an like it very much. |
Nice thread and lots to learn, however I am not sure which aspect to bother about in this whole game. I own a Nouvelle Platine BTW. Another thing, whenever there is a discussion of "well designed" TTs, the names that come up are Seiki, Technics, Victor, Luxman etc, all Japanese TTs. What about EMT ? Where do they stand ? Arent they suppose to be one of the best TTs of their age ? I know the 927 has achieved legendary status but why should we leave out the smaller models like 938, 930 and 950, they built to similar standards as well! I havent measured but I would guess they hold their speeds as good as any of the DDs and Idlers discussed here and have great bearings. However they are rarely discussed in this forum. |
Lharasim - My suggestion then, based on what I see in the video, and given the age of the deck, would be to get the power supply checked over and ensure it is in spec, check the electrolytic caps which can dry out. In my experience decent power supplies contribute hugely to the sound of a turntable, not just speed accuracy. For a few dollars you may get quite an all round improvement. |
Gentlepeople A simple dynamic load test you might want to try if you havent already done so, is to hold your finger against the rotating platter while playing music. No strobes, timelines needed just your ears. Can you hear a speed change? How much drag do you need to apply before a chance is apparent? Now the validity of this test is matter of opinion. But if we can hear an obvious change, one would think that there would likely be tiny changes due to stylus drag and that this would be at least subliminally important and deleterious. Again the method of drive/ control comes into play here and we each need to decide which does the least harm. |
After reading Salvatore review of the J Nantais Lenco, i knew i needed a bearing.After searching a lot i have found Dixchen on Lencoheaven who was making a bearing for lenco or garrard following the research made on twogoodears http://twogoodears.blogspot.fr/2011_11_01_archive.html You need to do to the middle of the page to see it. The difference with the lenco bearing is impressive ,more bass, silence during the playing of records, wider and mainly deeper stereo stage...It's not a small difference but immediately you listen and it's far better.It's more important than to change the cartridge. |
Mosin Hi Mosin thank you for your response. I am just an end user. I do not use a bearing. Nor did my vintage Granito model come with one. Sometimes when audiophiles really demand something, manufacturers sometimes have no choice but to start supplying it? You would know much more about this than me. It must be really tough sometimes? I could never be a manufacturer. You have my utmost respect Mosin in this regard ... as well as all other high end manufacturers out there trying to compete in this crazy market. The manual is very clear on the setup bearing. It is just that - a setup tool only. It should be discarded once set up complete Page 9. Using it imo is sacrilege. Defeating the purpose of the design. Re: the Platine. Unfortunately there are non-authentic tables out there worldwide from 20 different counterfeiting makers. These tables are out there with people using them. If anyone is unaware of this, see the Platine Information on the JC Verdier website for more info. To current/potential Platine Owners. As an owner of this table, the only advice I can give when buying a Verdier Platine - be careful to ensure it is a real Platine, especially if buying privately. If you are looking to buy one or already have one and have doubts, check with an authorized dealer or Mr Verdier himself to ensure it is authentic. Cheers |
Hello Dover no its a pioneer TT I really wish you would contact me offline about this ..but ok here goes... its a pioneer PL L1000A I have used this table with our own arm to great avail!! speed drift something like .00008% @ 33 rpm!! and possibly as or more important.... less then .00003%/per degree of temp change!!! IMMHO there is nothing out there that can compete with this very advanced hung motor rotor motor and its electronics... lots to the experimenter plinths or *nude* :) more to come Lawrence Fidelity Forward |
Ct0517 and all, Yes, I am familiar with Verdier's work, and admire I it. I am puzzled that his bearing doesn't seem to be in keeping with his papers, but I suppose that is a topic for another thread, not that I would say anything critical about Verdier because he did think outside the box. Verdier, Mitchell Cotter and others have written at length regarding the practical application physics in audio. If anyone thinks we are fumbling around in the dark now, I cannot imagine how it would be without men like them to at least challenge us to reach higher. |
Lharasim - I did read your response and had another look at the video. The "lurching" or "hunting" that I see occurs in the 1st 19 seconds before you put your finger on the platter. Did you have another finger on the platter out of sight ? From the lurching and hunting could I guess the deck might be an old Technics DD - maybe an SL1200 or early SP10 ? |
01-04-13: Richardkrebs
Hi Richardkrebs/Mosin Interesting thoughts. Based on the tables I own. Richardkrebs I agree with your thoughts as they would apply for DD and Idler but not for string drive. I would also revise the wording to read motor/controller instead of just motor - to be explicit. Mosin I support and agree totally with the concept you have described. In fact based on my direct experience I believe the Verdier Platine original design when properly set up, satisfies your conditions. Are you familiar with it? |
I just did some review of Kelly's posts. The missing link, I think, is the fact that he would say there is no such thing as a perfectly inelastic belt. (Such a belt would not bend around a pulley.) So there is no case where E = infinity in the real world. He does say that string drive and mylar tape significantly reduce the problem of belt creep, probably to insignificance but not zero. (I pursued this only to reassure myself vis my memory, not to critique belt drive turntables.) |
Halcro - Breaking newsflash - This Fatbob could have the magnetic drive, where the belt drives a subplatter and it relies on magnets on the platter to "lock" to the attracting magnets on the subplatter. They say it reduces wow and flutter by a factor of 10. Personally I would call this floppy drive - maybe thats the issue, certainly not as direct as a DD, idler, or thread drive.. http://www.positive-feedback.com/Issue50/transrotor.htm The main difference is the heavy platter in comparison to the Linn/Rega/VPI. The VPI's are driven around the perimeter of the platter, so they run higher speed motors. As far as motor for the Transrotor goes, I couldn't find any specs on the Transrotor whether its ac or dc. I assume no error correction but you could measure the back emf in the motor and use that to control speed, but there is nothing measuring the platter. As Richardkrebs says you have to engineer the motor/drive system/platter as a group. From what I hear in the video, my old Roksan, Sota & Townsend Rock TT's, which use rubber belts, would be more speed stable than the Fatbob. |
We all know the TT in Halcro's video was the Transrotor Fatbob. I dont think it is representative of a true "high mass" or "high inertia" TT for the following reasons - Platter is only 11kg - even Brinkmann suggest minimum 15kg Drive belt is elastic rubber - should be thread or inelastic material Most high intertia TT's use a small pulley and drive the platter at the perimeter. Because of this gearing ratio it enables you to run the motor much faster and reduce the cogging effect by increasing the number of poles per revolution. eg HM 1800rpm/4poles = 216 poles/revolution vs DD 33.333rpm/20poles = 20poles per revolution. The Fatbob is driven by small pulley, small subplatter which means the poles per revolution will be significantly less than the 1800rpm scenario, but more than the DD. So the Fatbob to me is an inbetween deck - mid mass platter , low speed motor, elastic drive and no speed correction. What is really disturbing is that despite what was demonstrated the magazine reviews describe its superior ability on timing rhythm and pace. When I cued up the same track on the Fat Bob, the recording became even more believable. The timing, rhythm, and pace were improved over the Leonardos.Obviously the reviewers system went from really bad to just bad. |
Hello Mr dovir I see you seem to not read my postings...again for the record that movement was because this particular TT has a hung suspension and when you put lateral side force thats what happens the platter moves...LOL no other turntable has ever been able to accomplish this task..Does it really matter?! maybe ..maybe not..but it clearly shows that constant change of load(big load) does not affect its speed stability...IMO this is a big deal if you like to play lots of different music(frequency extremes) like including organ music etc... Lawrence Fidelity Forward |
Pryso, Originally Ron Sutherland made the Timeline with a 'chip' programmed to flash once per revolution. Early on.......to make for easier adjustment of the 'flash' on an adjacent wall....he changed the chip to flash 5 or 8 times per revolution. He offerred to change my 'chip' free of charge if I had the old one but fortunately....I had the new :-) Regards |
Halcro, thanks for making and posting your video. I just viewed it and have a question I don't believe anyone else ask as yet. I'm not familiar with the Timeline, never having seen one in person. In your video there appears to be an initial flash on the wall above your FR arm, prior to your BluTak marker. Is that a reflection? I understood only a single flash was produced per revolution. Thanks. |
Dover, That Carol Kidd LP in the Linn label is a pretty good "audiophile" recording. Don't damage it on our account. A few years ago, I was in Tokyo and visited a well-stocked audio emporium. Here they had in one room pretty near all of the most expensive digital equipment in the world, to include Meitner, Accuphase, Esoteric, Linn, and Burmeister. The sales people left me alone to listen to any and all of this gear, using the very same Carol Kidd recording, the CD version. I sat there for a few hours and got a very good feel for the differences and similarities in SOTA digital at that time. (I was not blown away.) On the way out, I noticed that the store had for sale the LP version of the Carol Kidd recording; so I bought it. When I got back home, I was astonished to perceive how much better the LP sounded on my system compared to my memory of the CD, even when the CD had been auditioned on such high end equipment. This is not to brag on my system. This is to say that with all its faults, even with the faults under discussion on these interminable threads, analog still "rules". Incidentally, I do believe, if memory serves, that Mark Kelly showed that belt creep can occur even with a non-elastic belt. Also, a sophisticated AC re-generator for a 3-phase AC motor does not eliminate cogging, as cogging is formally defined. Such a controller can reduce or eliminate motor vibration and noise, where motor vibration and noise are due to phase anomalies in the AC delivery. "Cogging" can be reduced by the other strategies you cited, however. At least this is how I understand the art, and I am no motor expert. |
I agree with Dover. I watched Ct057's video, blew it up to full screen size, place the point of my cursor on the "33" and it is clearly lurching forward. However, I notice some lurching on my KAB disk which is a result of the disk not being perfectly flat on the LP surface. The warp, if you will, effects the movement of the "33" precisely the same once per revolution. So some of this observed lurching is from the imperfection of the KAB disk itself. But the lurching that is in sync with the finger tapping in the video seems to be the result of the platter motion and motor correction. What turntable is in the video? |
OK just for fun here's something to try on a Linn/Oracle/Clearaudio...take your pick http://www.youtube.com/watch?v=lwugFlbCOww I've recorded the KAB speed strobe on my Final Audio Parthenon VTT1 thread drive TT while I bash the record with my knuckle. Anyone else want to have a go - I used a Carol Kidd record.... from Linn. |
Richardkrebs Can you please review the video again. From 0-24 seconds you can read the 33 quite clearly, but the 33 is moving forward and back, it is not stable. From about 57 seconds on - he now has a constant load on the platter. 33 is unreadable, but it looks to me as though the surging has ceased. The conclusions I see from the video are : Unloaded, it is sort of speed stable but "hunting". Can you not see this ? Loaded - appears to me to suggest this deck is not accurate with a load ( blurred 33 ) but ironically the long term speed variation seems to have improved with the finger load on it ( less drift ). To be fair to the deck, the load on it probably takes the deck outside of its error correction operating parameters. |
Dover,Ct0517 IMO the timeline is really only good for testing long term speed stability at least the old one was....the Kab strobodisk will and can tell you more on the short term this is what i used in the video...no other turntable that i have used or played with could correct so fast that our/my naked eye cannot see! for all and anyone interested in what that tt was please contact me offline as i do not want to cause a rukus and or panic.. Lawrence Fidelity Forward |
Gentlepeople. Isn't this an interesting thread. Ct 0517, that was a great video. Thank you for sharing it with us. Good to see what a well engineered closed loop speed control can achieve. It was also interesting how fast the high inertia platter slowed in the translator clip. Tonywinsc has put very clearly the concept of inertia. In several of my posts I used the terms "radius of gyration" and "moment of inertia". I apologyse for not making clear what I meant by this. Radius of gyration is the distance where the mass of a rotating body appears to be concentrated out from axis of rotation. In the. 2001 space example this is almost out at the circumference on the station. Most DD TTs engineer the radius of gyration to be at some mid point out from the axis. In Dover's Final TT and most other belt drives or their derivatives, it is engineered to be further out. By calculating the radius of gyration and them knowing the weight of the platter we can calculate its moment of inertia which Tonywinsc clearly describes. I have the moment of inertia figure for the SP10 MK3. This is 1,100 kg/ cm. In other words in a rotational sense, the platter behaves as if it weighed 1,100kg with all of this weight at a radius of 1 cm. this is quite high for a DD. Good BD TT's as implied above will have higher moments of inertia than this. This is I think what Dover meant when he referred to "effective mass" . The key here is that for a closed loop drive, the motor torque capability, servo response and platter moment of inertia all need to be in harmony. The video the Ct0517 posted clearly shows the positive effect of this. Dev, you have asked for a list of TT's that approach the 3 rules. We could all build such a list. It is quite simple if you examine the TT under scrutiny. Remember this is a list of rules that would apply to TT that is impossible to build. Rule 2) is a catch all as it requires absolute dimensional stability between platter and arm board. It actually covers almost all of the requirements of a plinth design. This eliminates all TT,s that have, say, soft thrust pads in their bearings ( a trick employed to improve rumble figures )...allow any flex or bending of the plinth, have a soft Matt, excessive bearing clearance etc. The examples of breaking rule. 2 are many. Rule 1) has been covered in this thread quite well Rule 3) opens another can of worms. To suspend or ground. A tricky one as it depends upon where the TT is sighted. We also need to look outside out hobby field for examples of engineering where similar design criteria are required. High powered microscopes. Large telescopes. Aeroplane propeller balancing tables, are all areas where rules 2 an 3 come into play. My fear is that today, basic engineering is being ingored in favor of fashion. If we look back at the.. 70s and 80s we see fantastic examples from companies . Micro Seiki, Final, Technics, Sony, Luxman, Onkyo,Victor, et el, producing flagship models that tried to address at least some of these requirements. It is mouth watering to think of what the engineers involved in these designs could come up with today if they were given the R&D dollars. We live in ( naive) hope. |
Tonywinsc - my post was meant to imply the Bearing Design. Sorry for the confusion. The bearing being the part that is typically replaced. TonyWinsc - My tt has a hardened steel ball turning on a flat sapphire disc. It is not only very quiet, but would likely last for a billion cycles. At 33 1/3 rpm that is 57 years continuous running. My great great grandkids will be playing records on it. Oh I agree that all these tables will be around for our great great grandkids to use - if they want them. When you say very quiet - what is this based on? What tables have you compared next to it in the same room/gear to make this statement? By chance did these tables also have the same tonearm/cartridge on them as well going through the same gear? How many years does a billion cycles translate to ? Is longevity of an affordable bearing your prime consideration? These are not direct questions to you - just some considerations. I think when people come on forums and say something like "very quiet" it needs a reference, a standard that the personal opinion is based on. I will just say this. Sometimes, something needs to removed to be able to hear the difference it makes. Cheers |
Dear Tonywinsc: +++++ " So it is very likely that you could play a particular record one day and it seems to sound really great- pace is on and the music flows and the next time it sound kind of dead- all based on the randomness of the record position to the platter. " +++++ you are absolutely right and this problem is an important part of the non-perfect LP/analog medium. The LPs that I use on my self evaluation audio item method are marked to lower that " problem " and be more consistent during different audio item evaluations. In the past appeared a manual tool to center the LPs ( I think was named: Center-O-Disc or something like that. I remember it works fine. ) ) y used and I think I still have somewhere. Now that you brought this extremely important subject I will try to find out and test it again. I know I will have an improvement on quality performance level, no doubt about. Other than that device the only serious attempt to elimate the off center LP problems was Nakamichi through its 1000 TT model and latter on with the Nakamichi TT Dragon. I don't know how easy or hard is to the LP manufacturers to have their LPs with a " perfect " hole centered. Today we pay a lot of money for new LPs/reissues and the like but the LP manufacturers never fixed that problem and IMHO no one of them take care about. Regards and enjoy the music, R. |
Actually, high precision bearings are not that expensive. Balls with sub micron tolerances can be purchased for pennies- even in ceramic and ruby. Shafts can be had very cheaply that are ground to high precision tolerances. That is the product of an industrial base that today produces robust machinery that lasts 10s of million to 100s of million cycles. The markup that an individual may pay for a bearing at retail is 10-100 times the price that a high volume manufacturer would pay. A good example are the ball bearings in my mower deck. The autoparts store wanted $55 each for these things and I needed 6 of them. I bought the exact same bearings at an online auction site- a pack of 12 for $22. A large volume manufacturer can probably get them for less than a dollar a piece. Think I got junk for $22? That was several years ago and these bearings have lasted just as long as the factory originals. My tt has a hardened steel ball turning on a flat sapphire disc. It is not only very quiet, but would likely last for a billion cycles. At 33 1/3 rpm that is 57 years continuous running. My great great grandkids will be playing records on it. |
Hi Mosin regarding your Merry Go Round. As a manufacturer, I find you have left out a very important detail for us to consider. Please tell us what type of BEARING your merry go round uses. Is it something nice and smooth and slippery or does it float ? You see IMO - this is a total resonance vibration hobby. An imperfect sharp rock of various designs and angles that goes into an imperfect groove of an imperfect piece of plastic..... to make vibrations ........ In the last three years I have found as an amateur that the Achilles Heel for turntables I have owned - seems to be the BEARING. It also seems to be the elephant in the room. Pretty boring. You cant even see the damn thing. I think its still there. But the platter is too heavy for me to think about lifting it out right now. Will look later later.... Some squirt some oil in, others squirt in grease. Still others have found some secret product? Maybe it came from the moon? IMO - it contains the family jewels and is the DNA as far as how any of the turntables I have owned actually sounded. It is the ROOT. Put a TT motor right up to the Bearing or close to it the result is usually a turntable designed like a fortress (spaceship?) to protect against all those vibration / resonance nasties. Not that there is anything wrong with this - many ways to skins a cat here. How many people on this thread other than actual designers and manufacturers, know what type of bearing is contained in their turntable? How many know what the replacement cost is, and its percentage relation to the cost of your whole TT? Well here is maybe a little silver bullet for you in my humble opinion. Find this out and you may find out if your table was built for: 1)Performance 2)Profit 3)To win the beauty contest. 4)All of the above. IMO - 4 is the correct answer - Hey we do have to listen and look at it every day, and you want your manufacturer to stay in business right - for support ? For those looking to buy a turntable challenge your seller to give this information to you. Look.. I am done I think my vinyl journey. After what I have learned however as an Amateur, I would never ever again buy an expensive turntable without this information. So What if you find out that the $5000 table you are eyeing has a bearing that costs 68 dollars to replace? Would you still buy it ? This is just thought... So the BEARING imo is one, but not the only BIG Rock in this hobby. No more coffee for me this morning...sorry if any of this comes off as cynical.... |
Here is another thought to feed on our neurosis. (I hate to suffer alone :) Like I have said before, the tolerance on the center hole of records is such that the record Wow&Flutter is going to be around 0.5%. My favorite iPhone app will show you that too. It will show you the raw W&F as well as the filtered W&F of your tt. Last Winter, I filed out the center hole of my test record a bit so I could center it on the tt platter. It worked and I was able to reduce/change the record W&F. It is not easy to do. The outside diameter of records is not that round either. I had to try to center it relative to the grooves. But now, think about this. Your turntable has W&F in the 0.03% range and a typical record, say 0.5%. The two values are additive, so depending on the position of the record relative to the platter the total W&F could be 0.53% or 0.47% or somewhere in-between. (Min and max values worse case). So it is very likely that you could play a particular record one day and it seems to sound really great- pace is on and the music flows and the next time it sound kind of dead- all based on the randomness of the record position to the platter. Other than my test record, I have never experimented with this concept. I try not to think about it. |
Your tt platter is a flywheel. Like any good flywheel design, the bulk of the mass is on the outer edge (Think 2001 A Space Odyssey). The moment of inertial equations illustrate the effectiveness of having the bulk of the mass at the outer edge. A uniform mass flywheel is I=1/2mr^2, but when the mass is concentrated at the outer edge it is I=mr^2. The moment of inertia is doubled. Therefore, a "hollow" flywheel half the mass of a solid flywheel has the same moment of inertia. And the moment of inertia is directly related to the amount of torque it takes to accelerate the platter- double "I" and torque must double to get the same amount of acceleration. Conversely, double "I" and the impact of stylus drag change on platter speed drops by half. |
Hi Dover, one thing to quickly recalculate is that the record spins 0.5556 revolutions per second. (Inverse of 1.8) So the speed error would be 0.008% if it takes 7200 seconds to lose/gain one rotation. What I believe is that we will hear a difference in PRAT if speed is off before we hear sour notes (tonal pitch); at least most of us. If speed is off by 0.1%, then concert A would be off by 0.44Hz. I do not think that I could tell the difference even if I had a tuning fork to my ear. But I now know that I can sense the pace of the music by small changes in speed. An orchestra, for example, tunes to the oboe. If the oboe is off a Hertz or two, it doesn't matter because the whole orchestra will be matched to it; but the tempo of the music doesn't change- can't do that with a recording. |
I am wondering that every Turntable discussion is based on speed only. Like Dev wrote, it is the beginning and it is important. But is that all? A little more knowledge should be available I think, we have the year 2013 now and serious High End has 5 digits or more and a lot of owners want to spend that money - Quality and Influence from the Bearing - Quality and Influence from the Chassis - Quality and Influence from the Belt - Quality and Influence from the Platter - Influence from Suspension and how it was solved - Why are some platters so heavy - Direct Drive works with continuous correction, what is the sonic result - Platter weight from DD and their sonic attributes - Weight in general and why - Is a polished frame good for sonics - Idler Drive has direct contact to Platter and Spindle - Advantages / Disadvantages - Speed correction or not - What material is used and is it stable over the years - suspension for Idlers, necessary or not - sonic results from contact motor to platter - isolation from internal vibrations in general - is reliability important or not - do Fangroups replace knowledge - are facts welcome or do they disturb dreaming - why are no turntable manufacturers found in such discussions - is analog the last resort for "I-do-what-I-want-and-who-cares-Design" - what is a stable Design - why can a unit change Performance when your wife opens the window - what is sonic feedback and so on and on |
Dover, As 'stylus drag' must vary with the modulation of the grooves responding to the complexity and dynamics of the musical performance.......it would not, I think, be a constant? If you merely adjust your speed-controller to hold the Timeline constant with the cartridge tracking........it would be interesting to see where the Timeline 'mark' would be at the end of a whole side of a powerful symphony such as The Royal Ballet, The Three Cornered Hat, Pines of Rome or Witches Brew? |
Okay, let's go further. Do you think a special merry-go-round could be built for the little girl, so she could spin as many kids around as you can? This goes to torque, and how one might approach building a turntable with a low torque motor, yet having mass applied so that performance would equal a turntable with a high torque motor. I suppose the point here is that there are quite a few ways to skin the proverbial cat. |
Mosin - Absolutely right, I used mass loosely. I read somewhere the EMT idler has a platter of 5.5kg ( same weight as the copper mat on my deck ) but due to its weight distribution ( 16 & 1/2" platter ) is the equivalent of a 50kg solid platter. Although not as radical my TT has an inverted bearing with a substantial subplatter which is an inverted truncated cone (frustum), so most of the mass of the 20kg platter is between the inner and outer grooves & the thickness increases inside out ( and below the bearing point ). So yeah the effective mass of my TT platter is well in excess of 20kg. |
Halcro/Tony I've just done the Halcro drop test of dropping the stylus on and off without adjusting the speed. The fall off in speed is minute. I would estimate it would take a couple of hours at least for the error to translate to 1 complete revolution. So according to my rudimentary maths for my TT 1.8seconds per revolution/7200 seconds ( time to complete 1 rotation error ) = a speed variation of 0.025%. Even an hour would only be 0.05%. ( Tony correct me if I'm wrong on the maths, my brain is disfunctional at the moment ). With the speed adjusted for the tracking weight there is 0 drift. To me the big question is how consistant is the impact of the stylus drag on speed and if error correction is used, is the bark worse than the bite. This will no doubt come back to the quality of the particular solution offered. |
From Dover's post, "The point I take from your Goldmund example is that you are suggesting that mass alone will not provide stability with a motor that simply doesn't have enough torque to start with." Let's think about this for a minute. Is the platter solid? Where is the bulk mass located? If the platter is solid, most of the mass is toward the outside, correct? Is that where it should be? One would assume that it should be because almost all turntable platters are made that way. But, it it really the right way to design a platter, regardless of the drive type? Now, let's make some analogies. 1) You have a playground merry-go-round with six kids on it. They are positioned towards the outer rim. 2) You have a playground merry-go-round with six kids on it. They are positioned, so that the merry-go-round is perfectly balanced from center to edge. 3) You have a playground merry-go-round with six kids on it. They are positioned as close to the center as possible. All the kids and all the merry-go-rounds weigh exactly the same. Which merry-go-round is easiest to control, if you are the guy pushing it? Would a scenario exist where it be possible for a small girl push one of them, but not the others? I submit to you all that platter design is the most seriously overlooked aspect of a turntable. Location of mass matters, and it matters a lot. I consider the platter to be more key to the sound of a given turntable than drive type, or speed accuracy for that matter. Disclosure: I manufacture idler drive turntables with speed controllers. . |
