It seems like half the new LPs I buy these days are shaped like soup saucers, so I broke down and bought an Orb a few weeks ago. I love this thing! Flattens dependably without affecting sound quality, unlike the old Vinyl Flat I used to use. Excellent product.
How best to eliminate LP warps
I own about 2500 LPs, and I like to think they're flat. Furthermore, I espoused the view that warped LPs ought to be discarded. But lately I have found 2 or 3 of my LPs that do have warps but sound too good and are too precious for the music recorded on them to throw away. So I am in the market for ideas on how to remove warps. I am aware that there was a device on the market that looked like a large waffle maker, to be used for warp removal. I think Furutech made it, but I never see it advertised these days. I am also aware of the DIY method of placing an LP between two glass plates and heating the ensemble. The question there would be how hot and for how long? Any suggestions are welcome, especially opinions on the efficacy of the Furutech. Thanks. Please no comments on vacuum hold down; I think it's a great idea but none of my five turntables has that feature.
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There was a period where the Furutech DF-2 was no longer being shown on websites. I had the impression Orb had discontinued it and Furutech was no longer carrying it. Within the last year, I noticed a bunch of Furutech DF-2 units for sale- new. Price is higher now (big shock). It is pretty idiot proof, doesn't require rings and my experience with it--say 8 years- has been nothing but positive. I don't know if retailers have some wiggle room on margins here, but worth exploring. There is an even fancier Orb - the DF-3- which has additional features. One person I know who has an old Orb and the DF-3 found the latter to be less than optimal. I have not used it. |
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@bslon , I made my "donuts" out of felt. Works great. |
A couple months ago I emailed Phillip Holmes at Mockingbird about the Orb Record Flattener. If you’re interested, I received this email from him today: Hello,
If you already bought an Orb DF01ia record flattener, please delete this email. If not, please keep reading.
I took a break from selling Orb record flatteners. After the positive review by Michael Fremer, the problems I had with getting stock just got much worse. Before the review, it was difficult: it's difficult to get them here (customs clearance, etc..), they are back-ordered, they are huge, they generate a lot of questions like "my record didn't come out absolutely hypothetically perfect, am I using it wrong...", "when will my machine arrive", and so on. So I haven't sold any since November. If you are interested in placing an order, and waiting for them to come in, I will work with you on pricing. But I assume it's going to be 6~8 weeks, maybe longer. I contacted the factory, and I am waiting to hear from them on the delivery time.
People are confused about the "plus" model. Grooveguard is the raised edge and label area on most normal vinyl pressings. They created that feature to protect the playing surface from record changers, hence it was "grooveguard" because it guarded the grooves. The "+" version is the same as the regular version, except for the inclusion of plastic sheets to protect the playing area on records that are flat, meaning they don't have a raised outer lip or raised label. The records without a grooveguard (without a raised label, without a raised outer lip/rim) fall into two categories: very old pressings, and 200 gram audiophile pressings.
With a pair of scissors, some parchment paper or poster board, you can create your own versions of the plastic sheets that cost an extra $200. Just think "paper donuts", and you have the concept. If it is smaller than the record, but fits around the label, it's the right size donut. But, if you want the official plastic sheets, the plus model works fine!
People often ask about "will these work on American outlets"? Yes, they will accept regular 120VAC North American power.
A little backstory: I am a nurse, mostly because I don't like working on and talking about machines 24/7, and people are more challenging (and potentially more rewarding). I work at a county run MHMR in Texas, helping people with mental illness and addiction (usually both). So I am not available during "normal" business hours.
Best Regards, |
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@jazzguy43 , I would suggest that it is more a matter of correctly applying the laws of nature to a given situation that matters. Second Law is especially tricky to use - I’ve seen it used to explain why methane explodes in an enclosed volume, but not otherwise. Of course, it was a bogus ’proof’ - tipoff was that it did not use the particular properties of methane. Experiment is always better than derivation, if feasible, although I’d be the last to abandon the latter. |
Jazzguy, your principle holds if warps are always the result of local expansion or shrinkage of the vinyl disk. But you can also take a perfectly circular disk and twist it so it becomes”warped” in the horizontal plane (viewed on edge). Such a disk could be flattened and remain circular in the vertical plane ( viewed from above or below). Not sure what this has to do with entropy, but I’m all for it. |
hmmmm, if materials behaved this way the second law of thermodynamics would be broken! I encourage you all to read about entropy and IRREVERSIBLE energy! It is a fundamental foundation of how the universe works. There is a real difference between science and science fiction, having a warped lp remain round after removing the warp is FICTION! Furthermore, on the flat edged lps using two pieces of glass in the oven WILL MAKE IT FLAT; no question, but all the groove tops have been flattened as well! You can all believe what you choose, a good start is a BS in ENGINEERING or PHYSICs! I am a retired nuclear chemical engineer who believes in the laws of nature that are explained through mathematical relationships. |
Here are the general steps: It will not totally get rid of the warp, but the severity of the warp will be greatly lessened and your LP will play with no discernable · Hey Lew, This thing really works.
Regard: |
I got more fussy about warped records when I doubled down on record cleaning methods and noticed how many records don't lay truly flat on the platter- using a Monks, rather than VPI, RCM. I used the Vinyl Flat for a little while, it could work, but time consuming and very few benchmarks for time and temp-- I used an early one with a Groovy Pouch™ and single temperature-- some people got orange peel from either overheating or over-torquing the nut or both. I eventually bought an Orb- a Furutech branded DF-2. I'd say if I guesstimate duration of heat cycle correctly based on type and severity of warp and thickness of the record, I have a roughly 85% success rate, which I consider pretty high. Some records, even when "de-warped" will not be playable--the groove takes a bend where the warp was, and flattening it does not put it back "on track"--- Why so many warped records? I buy a lot of used records, many from the early '70s- period of much change in jazz--and a real low point for vinyl in the States, as everybody knows. I found a seller with a stash of Nathan Davis records on Segue- bought several from him, sealed. Pressed on the thinnest vinyl imaginable- makes Dynaflex look like a truck tire. Did get these flat but I watch my linear arm hunting and wandering--the record is out of round. Which makes me pause when you consider how expensive cartridges are today. Replace the record- maybe-- I've certainly bought more than one copy of some records in the quest for a better copy (condition, surface noise, etc.) Some of these records are not so easily replaceable. The machine has, for me, paid for itself. Oh, I remember asking an online seller to confirm a record was not warped. He wrote back saying "you'd have to be an idiot to sell a warped record on ___." Guess what? (It wasn't a hard to find record). |
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smatsui,Thanks for the heads up. Seems to be a great opportunity for someone with enough 'bent discs' to spring for one. The last album that I got had a sort of double warp, i.e., one right after the other! |
The Vinyl Flat and Groovy Pouch has worked great for me. I got one for my birthday in March of this year. Every warped record that I've tried to flatten came out nearly 100% flat. I first preheat the Vinyl Flat in the Pouch to 130-140F. Then I put the LP in the Pouch at medium temperature and monitor the temperature to keep it 130-140F. After 2 hours, I unplug the Pouch and let the Vinyl Flat cool while still in the Pouch for another 2 hours. Every record, both brand new and used ones from the 70s and 80s have come out flat. |
I'd say unless the record is unplayable live with minor warps. I've tried traditional and modern methods of trying to flatten reocrds with varying degrees of success. Last machine used was the AFI Flat. Most of the time it works pretty well, but it has ruined several records including a numbered Blade Runner soundtrack on red vinyl and a sonically mint early pressing of Fleetwood Mac Rumours. The Blade Runner was a strange one as I had successfully flattened many colored records but QRP must have used some non-standard vinyl formulation that made it susceptible to heat damage. After treatment a rough orange peel pattern appeared on the record and it was unplayable. Other owners of this record have also experienced ruin using a variety of de-warping methods. Caveat emptor when using these devices. |
@poorguy I never learnt what the metal was that is used on the AT-666. I know others use this mat on this forum, and it might be possible to learn which metal is used if a wider inquiry is made. I also know through this forum, it has been used without a Vacuum and has been rated as an attractive method, I have not heard the mat used in such a way, but would try it out in the near future, as I will be visiting the owner of the one I have tried out. Again there are AT 666 owners on here who can offer a description with almost immediacy if willing to help. The AT 666 is not always going to be able to successfully hold a Vacuum for a full period of a side of a LP, their age is contributory to this, the length of time the Vacuum is in place is a unknown, some do not produce a Vacuum anymore. With the above in mind, it does suggest careful selection is required, when purchasing, if a Vacuum is the important function for the mat.
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PVF, Perfect Vinyl Forever can flatten records for $12 each. They mainly clean records, but also offer this service. Minimum order is 12 records. I them once with impressive results. I did not however send a warped record to be flattened. Using a machine that costs hundreds or thousands of dollars may be appropriate for say an audio club, but for the average collector, it is too high a price. PVF uses a professional machine manufactured for this specific purpose. No electric blankets involved. |
@lewm On this forums analogue section there are very few posts from a small selection members, which can appear when an individual beats the drum on a subject, that it is something that is ubiquitous and all are needing to heed the concerns raised. That is not the case, I am only offering an account of my experiences encountered and nothing else, as said I have been touching base on this subject for many years and have latched onto various information that is in keeping with it as and when discovered. My earliest experience, where I have shown concern for a bearing condition prior to having modification carried out is when I cleaned out and decontaminated a Bearing, to allow for a Lubrication oil change on a Belt Drive TT, but I would not align that sort of activity with a Bearing Modification. As said, I have been interested in the condition of a bearing housing on a owned TT for more than 20 years, this interest started with a Garrard 401, that was sent to a engineer renowned at the time for their work who modified the assembly. It was this experience that left such a good impression, that made myself be more concerned for a Bearing on a TT, than I would suggest is the common level of concern met, in recent years. This same type of level of concern has been made toward the Tonearm, and I no longer use certain Tonearms, as I have a arm that has been overhauled, using modern materials and machining tolerances that suit these materials, once more the experience of such design when encountered is a compelling attractor and indelible, especially enough to not want to continue with the other owned Tonearms. In relation to a TT Bearing, my interest commenced more than 20 years past and during this period, the interest was ignited on a few occasions, but especially through the forum Lenco Heaven. Through LH, I have been both observing others work and meeting with individuals involved with the forum, who have been working with improving Bearings on the TT's, this work has been observed from many areas and methods used have been duplicated by others. The Lenco and the Garrard TT's are now able to have Bearing assemblies supplied as Commercially Available Products as an exchange part, that are using the basic principles for the designs produced by the forum members enthusiasts. The general ideas for the designs are to remove Metal to Metal Contact. The use of Non Metal Modern Materials used for the role for replacing the originally used metal sacrificial parts, along with a design intent, that is creating a interface with a accurate/consistent dimensions for the tolerances between the moving an passive parts has been a method that has become quite common in todays bearing assembly designs. I have been invited in the past to take part in assessing the differences between a bearing assembly on a Idler Drive TT. Three Bearing were available that are quite easy to swap out, the TT's Chassis had been specially treated to minimise Flexion occurring and effecting the Bearing Spindle. One Bearing was original with an added lubrication only to a Bearing Housing. Another version was a overhauled Bearing Assembly, based around the original. The other version was a Modern Material designed Exchange Bearing with a Composite Spindle and where Hydrodynamic Lubrication was claimed to have also been achieved and the flexion that can occur to a Bearing Housing was substantially reduced. All the above demonstrations took place on the same TT > Tonearm > Cart' and Mounting Method and the attraction toward the Modern Material Exchange Bearing, with a attention to the Lubrication Method and Reduced Flexion, is a version when encountered is quite compelling, it is an indelible experience, needing to be experienced for longer than the alternative versions. What I can suggest without reservation, is that a change of Lubrication Only within the Bearing Housing, is a method I will am not recommending, it the TT is to be used extensively. To fall into the mindset that a oil change only on a TT that is with a unknown history of usage and the present owner not having any knowledge of the quantity of rotations and the conditions those rotations have occurred in, is a situation that is enough to warrant the notion that a further investigation of the Bearing Assembly would be a good practice. Caution is a best practice to be used, if improveing on the condition within the Bering Housing is wanted to be pursued, a skilled individual in such practices may be best consulted with to be a reassuring support. When I transferred over from Idler Drives to Vintage DD TT's, I acquired TT's in the usual manner, as I viewed these as projects and purchased at a project value. To have made a purchase of TT's that have shown a excessive movement from the Spindle was not intended or even considered as the condition that would be most concerning, especially when the play detected is the worse movement I have detected from any spindle bearing I have handled. It has been this experience that has encouraged myself to make it known that when considering a Vintage Japanese DD TT, that not only the Electronics might present an issue that is a concern. During my broadening of the discussions on the subject of discovering an unwanted Spindle Movement on DD TT, there has been others come forward and make it known that there has also been similar finding on their owned Vintage DD TT's. On the subject of detecting a play on a Spindle within the Bearing Housing I am not alone, having a few Compadre from across the Globe reporting on a similar finding. Again, at no time have I suggested there is a ubiquitous issue with a Vintage Japanese DD TT. I happily receive comments from TT owners who are not detecting anything concerning on their owned TT's Spindle, this is the best scenario and is the one I wish for all to encounter. I happily spend 'some of my time' learning about the overall requirements to get the best from a Vinyl Source, Mechanics, runs parallel with Geometry and Electronics, I am quite balanced across all the necessary disciplines to be understood, and choose the parameters that are the most attractive to myself. I share my experiences and reference the experiences of others, for the individual leaning toward the idea of purchasing a Vintage Japanese DD TT. It is for the best, if they go into it with their eyes wide open, using the knowledge that is available to them. It is no harm for a wannabe purchaser, or owner of a TT, to be aware that a Bearing Assembly might come with or have a condition that is not ideal, and is another to be added to the usual concerns seen for the condition of the Electronics. As always we really want the supplied product to be one with a minimum of markings on a almost pristine Aesthetic, as the only bug bear, but wants and realisation are quite different when it comes to Vintage.
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Pindac, Please forgive me if I offended you in questioning the idea that TT bearings and their shafts commonly wear in the horizontal or lateral direction. I only meant what I actually wrote, that I have never seen it or heard from others that it is a common problem. As you may or may not know, I have a fairly extensive experience with vintage turntables, especially DD types, so my query was based on personal experience and past history with Technics, Denon, Victor, and Kenwood DD TTs. I also have extensive personal experience with Lenco and briefly with Garrard idler drive types. (Although there was nothing amiss with the spindle and bearing on my Lenco, because the Lenco was NOS, I did replace the entire assembly with a massive aftermarket spindle and bearing custom made in the UK.) I once commented on your subject by wondering out loud whether the lateral wear problem would possibly occur with a belt drive TT, where there is in fact a lateral force constantly in one direction on the spindle. I certainly do agree with you that vertical wear on the bearing and/or thrust pad is always an issue that should be addressed when one is putting any vintage or "pre-owned" TT into service. We have no disagreement there. It would seem to me that if the spindle is wobbly in the bearing shaft, there is no solution at all except to replace the entire assembly with new. |
Tea Total is the Key, no fantastical stuff, followed by just a pure curiosity to learn a little about the what would be the best for the Vinyl Source. For me it lead to the best environment that a Stylus can be functioning in. In a very layman description, Vinyl Condition and Cleanliness/Purification within the Groove, Operational Energies Transferred to the Styli, Energies Transferred from the Styli. I am fortunate to be able to have a support form very adept individuals, who are known for being able to produce methods or carry out work that reduces the effects of the above. To receive a demonstration of a Vintage TT, with a modified bearing housing, using Modern Materials machined to be a best fit and have a lubrication that is hydrodynamic, is something when encountered is quite indelible, it is as memorable as the song 'Summertime', and has a similar impact, as once heard, one is happy to hear more. I have a friend who took these ideas, to a further level and had a Spindle Produced that has a Steel section within the Bearing Housing and a option to use a Variety of Materials that are in contact with the Platter, there material of choice when I was demonstrated this design was Ebony. My interest in the subject is no different to a savvy Modern Turntable Producer, they are looking at the similar materials and choosing these to work with their own dimensional tolerances for the materials to interface, this will then allow for their selection of lubrication that best suits those chosen materials and selected dimension tolerances. On the subject of a Warp, I have tried out a AT-666 Vacuum Mat and was not satisfied with the sonic trait and how it was perceived as influencing the SQ during the replay. I do intend on owning a AT-666 and trying it with different materials under it and upon it the LP, to see if the sonic trait can be altered to one that is being perceived as more to my preference. As usual these outcomes are all subjective, and the usual undertaking of later arranged group demonstration, along with the variety of listening sensitivities that comes with a mixed group, could easily produce a host of mixed assessments, that are the antithesis of ones own. Not being Selfish, the final choice, does belong to the end user, but sometimes the comments made from others, does help with pinpointing traits that one may have been overlooking during their own evaluations.
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At no time have I made it seem like it is going to be a common discovery to encounter a TT, that has a Platter Spindle housed with Interface materials that are showing excessive signs of wear and the most likely cause being, the interface parts are doing, 'as said on the tin' and having a service life associated with being sacrificial and expected to yield in their soundness by design. The fact is that it does occur, an interest in the subject can easily show cases where discoveries have been made. I have hands on experience of these unwanted conditions having occurred and through discussions with others face to face and through using a forum as communication channel, knowledge becomes available of unwanted conditions that have been discovered within a TT's Platter Spindle Bearing Housing. I have no beef with anybody who does not care for the subject, but as there are many who visit forums, and somehow end up with a desire to buy into a Vintage TT, it is no harm in informing them of a condition that they might inherit as part of their purchase. It is for these reasons only that I keep the subject live. I have been instrumental without making any profit, in helping some Vintage TT owners acquire a necessary part to overcome a condition that has been wanted to be remediated. The conditions have not been fantastical as seems to be suggested by a few members on here recently, but quite real and enough of a concern for the TT owners to seek guidance to correct the condition. A Individual who is buying TT that has been a model available in the used market for a very long time and especially the Vintage Period, can be supplied a TT that has a condition in a Bearing Housing that might need a rethink and corrective measures used to make an improvement. It is best to identify with this being a Possibility prior to going down the rabbit hole, not all users of TT's are settled with the idea of carrying out surgery on them, the very idea, might make them feel quite queasy. I know a individual who has a well respected Japanese Vintage TT, one that quite a few would aspire to own. This individual has been quite proud of their TT and had made it known on a few occasions, how they would be happy to have it used in a Line Up at a Bake Off. This same individual when stumbling on a discussion about Bearing Condition on another forum, was to become a vehement adversary to the notion their TT could be in need of a overhaul of the Bearing. At a later date a Off Board Key Strobe was used and a discovery was made that encouraged the individual to suspect something was amiss. The investigation lead to the Bearing Assembly, and the result of the investigation was such that the Bushes were showing signs of excess wear and the Interference fit Ball was with a scribed surface. This individual was aware of the work was having done on a identical model TT, and inquired if they could queue Jump, as they were not wanting to use their TT, in the condition it would be in if reassembled using the Vintage OEM Parts. I agreed to let the other TT have the work carried out in advance of my own one. The Engineer tied up and the work run on longer than planned, the TT owner waiting for their bearing parts to be produced, bought in another identical model TT, to use as a stop gap. The having the possession of two TT's got their thoughts going and two identical Plinths were produced from the materials of choice. The Identical Plinths and Same Model TT's was now in a position where both versions could be A/B compared using the same Tonearm and Sub Plinth Structure. The outcome of the A/B testing was quite a revelation, the Original Parts TT, did not survive the whole of the selected tracks to be used during the comparisons. The TT with the Bearing Parts using a modern approach and modern materials was the much preferred, they claimed it was like two different TT's. The Vehement Adversary to the notion, was now making appraisals for the changes that were not present prior to the first experience of the new design bearing assembly. There are now in place other additional methods that have been adopted for use by this individual, they are convinced that looking after the bearing assembly and housing are key to creating a valuable improvement. There is now a method produced to rigidly fasten the Bearing Housing. The curiosity has not stopped there, there is also one of the TT's with a Lignum Vitae Bush and Thrust Pad produced, that is yet to be A/B demonstrated between the two modified TT's. A Worn Thrust Pad is the most likely to be expected, many that are inspected for wear will usually show some form of indentation. It is quite common to see a Thrust Pad that is interfaced with an interference fit ball in the base of the spindle, to have shown an ellipse shape as the wear seen formed at the indentation on the Thrust Pad. This condition serves as an indicator, and suggests the Spindle Rotates of Axis. Another condition reported on, is a flattening of a Steel Ball and another much more unwanted condition, being a scribing on the surface of the Steel Ball, I have been shown these conditions first hand and have seen it presented as an item needing to be corrected on other forums. It has also been a subject shown by a respected service engineer, who is referred to on this forum regularly. This is not a fantastical idea, it is real and it occurs. The Bushes are probably the hardest item to think of as showing a Wear, but again they do. When the condition is present, an eccentric rotation is most likely to occur, the longer the period of rotations, the longer the exposure to operating conditions that can increase the wear, resulting in increased Bush Wear and an increased eccentric rotation. I have had my fingers on Spindles that have been able to produce a Tapping Noise when gentle finger pressure is applied. I know of others who have been able to produce a Tapping noise as well, using similar lightly applied finger pressure. It is not a fantastical idea, it occurs. I like to think that when a individual has a TT in use with an unknown usage history, they are fully confident about the condition of the TT's Bearing Assembly and that is is functioning to a standard that is mechanically sound. The idea of a very expensive Stylus interfacing with an LP Groove that is most likely eccentric in rotation due the pressing of the LP, and then this being amplified further by the Off Axis rotation of the Spindle, is a condition I wish to avoid. I have taken a few steps to overcome across many years, and have had Bearings Overhauled by a Specialist Service, or alternatively Supplied as a New Design to be used on a Vintage TT. As always 'each to their own'. If there are individuals not wanting to concern themselves with the the possibility for mechanical issue being present, that may be a concern, within the assembly of the Bearing Housing, that is fine. At no time have I made it seem the enjoyment of music is not to be had on any condition of a Bearing Assemblies Parts. Alternatively there might be an individual who is aware of something that is a concern to them, then stumbling on these types of post's might be enough to motivate them to learn more, there can be no harm in that happening. Then there are the types that like to think the Bearing Assembly is able to be brought up to a very high specification and has exchange materials in use that are modern and fit for the purpose of the role they are selected for, I'm sure those types really enjoy stumbling on Post's that cover the subject of carrying out such work.
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@mijostyn Not kidding at all. I wouldn’t do this for just anybody, but I took a highly warped record and laid it flat on the platter. Dished up about 0.195". Put the ’washer’ in place, put the record down in the same position, put the 2kg weight in place, and measured less than 0.028" by feeler gauge. A 0.028" soft feeler gauge was the smallest soft gauge that I had, so the actual corrected dish may have been quite a bit less than that. That’s reduction of a severe dish by a factor of 7 or more. And that’s with a first generation ’proof-of-concept’ washer. My next one will be a precisely made CNC piece, specified to a strict mathematical formula. The washer and its shape make all the difference. |
Two mechanical comments on warp removal. 1. Sometimes you just want the record flat for recording purposes. I have used small pieces of transparent tape with mostly good results. I tape over about half the lead-in-groove width and adhere the remaining tape to the vertical edge of my platter. This usually moves the warp a few inches away so that more tape is required. If more than three pieces of tape are required it’s usually not worth the effort as the warps will just continue to appear. Extreme care must be used in placing in the stylus into the first track to avoid catching the tape. I use the arm lifting mechanism to lower the cartridge.
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@mijostyn A spindle within a Bearing Housing and rotating being guided by Bush Parts with excessive wear on the inner walls will allow for the Spindle to take on a eccentric 'off axis ' rotation. As said it would be good to know if the device was able to detect this being present. |
@slaw Don’t have a picture yet. I’m still finishing the DIY air bearing tonearm - just installed the Koetsu, and it sounds even better than before. My platter has a 0.008" recess for the label, so to implement the reflex clamp I needed a washer to correct that as well. My first attempt is a 3" diameter black Delrin disk, whose outermost 0.25" is 0.008" thick to correct for the recess. The disk then rises to 0.055" thick at the spindle. Flat side is down, obviously. Design is after "Niffy" at DIY Audio. @mijostyn Your intuition is flawed. It works as indicated. |
@terry9 The washer goes under the record. Reflex clamping will not flatten a dished record when the convex side is down. @pindac , Interesting device. Eccentric spindle holes are certainly a common problem. The industry standard is within 0.2mm of dead center. It would be very difficult to make an off center spindle as the spindle is usually machined as part of the bearing. Laths do not make items off-center. With a sine wave you can hear and see off center (on a scope) easily. Complex music is another thing. It would be interesting to see how far off the hole would have to be before it became obvious with music. What to cut up some records? |
@drbond In relation to your inquiry about eccentric rotation, the Link might prove to be latest commercial device on offer to confirm the amount of Off Axis eccentricity being produced. It would be good to know if this device is also able to measure the Spindle being rotated in a Off Axis Rotation. |
@terry9, yes something similar can work for some dished records. However I had a Kuzma table which utilized a washer (diameter no more than a quarter) and threaded clamp and I only had partial success with that. But you mention a thin beveled washer over most of the label. I've never seen one like that. To me, to be effective it seems the clamp must have a greater diameter than the washer for it to be able to push downward on an unsupported portion of the LP. So I don't understand how a washer that large could work? |
@pryso , very true about warps and dishing. I send the dished records back. It is almost impossible to seal the convex side. In order to hear the warp easily you have to have some steady tones like a cord held on a piano. Sine wave test records really demonstrate the effect of warps and off center spindle holes. When a turntable compensates for everything except the offset spindle hole which there is no compensating for, with vacuum clamping and rock solid speed control there is a sensation of solidity which greatly adds to the illusion. I can not tell you if this is psychological or not as I have not performed that experiment. It seems to me to be quite obvious but, out brains are powerful items and you should never write them off. |
