Warped record playback


I have recently bought so many new LPs that turn out to have, to some degree or another, edge warp that I am wondering what to do. Equipment-wise the situation is now this: I bought a new Rega P9 and Kontrapunkt B a few months ago and put my venerable AR ETL One up for sale. Despite some discussion, it has not sold. I am always leery of damaging what is for me an expensive cartridge with a nonuser replaceable stylus by playing warped records. I am also leery of doing harm to the stylus by playing records (whether new or used) that have, to use a polite term, imperfections. What if I kept the ETL One, sold the Rega RB 300 arm and bought a different arm and a new cartridge optimized for tracking of warped records. Am I wrong in thinking that an arm with lighter effective mass can negotiate warps better? What would you recommend insofar as such an arm and relatively inexpensive cart to go along with it? I might have done myself a favour by not selling my Shure V15 V mr, but it's too late now, it has found a new home. The other problem also being that my phono section only has input for one turntable. Any suggestion, short of plugging and unplugging as needed, to get around that one. Thanks.
pbb
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Warped records ceased to be a problem when I bought (decades ago) a Sony PS-X800 table with linear tracking Biotracer (servo controlled) arm. It will track anything. Really amazing.
As a general rule, linear trackers with a properly aligned cartridge are much better at dealing with problems in vinyl.

As far as cantilever deflection goes, that will have to do with the severity of the warp. An abrupt rise will surely result in cantilever deflection, regardless of how well the arm and cartridge are dialed in and matched to each other.

Since the cantilever is the bridge between the contact area of the diamond and the pivot of the tonearm, you would have to transfer enough energy from the diamond into the cantilever to cause the suspension of the tonearm at the pivot to react accordingly. Since direct physical transfer of energy is what is taking place, it is only natural that the cantilever itself would deflect prior to passing that energy onto the arm, causing it to respond. After all, if a severe change in vertical terrain doesn't cause cantilever deflection, how could those microscopic modulations within the groove deflect it enough to produce a signal ?

If this is what you are running into, you need to either get rid of the record and / or find a way to reduce the severity of the warp. There is nothing known to man short of the "Laser Turntable" that will play severely warped records. Even with a vacuum platter and linear tracking, i won't attempt to play something that is severely warped. If you are running into this with anything less than severe warps, either something isn't dialed in correctly and / or your arm & cartridge aren't that great of a match.

As to your question pertaining to swapping arms / varying arm mass, lower mass arms won't work any better than medium mass arms if the cartridge is properly matched to the arm in use and the entire assembly is properly dialed in. What going to a lower mass arm will do is provide you with a far more limited selection of suitable cartridges to use. Most MC cartridges will not work optimally in a very low mass arm, so you would probably end up with a high compliance MM ( Moving Magnet ) or MI ( Moving Iron aka "variable reluctance" ) type of cartridge. As such, sticking with a medium mass arm and finding a suitable candidate in terms of a cartridge would offer you the most versatility for future use. Then again, MM cartridges will probably be in production longer than MC cartridges due to higher output levels and wider use by non-audiophiles. There are quite a few good MM cartridges out there, but not all of them will work real well with a low mass arm.

As a side note, cartridges like the Shure or various Stanton's and Pickering's with a "brush" act as a "dynamic shock absorber". As such, tracking can be improved but you run into other problems with this approach. Whether or not one finds this to be a worthwhile trade-off is an individual preference. Having said that, one could own / use such a cartridge with the brush lifted or removed and then take advantage of the improved tracking / damping characteristics of the brush on an as needed basis. Obviously, one has to adjust such things as the tracking force when switching between brush / no brush, but that is typically a simple matter on most arms. Sean
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I agree with Lugnut that it seems fundamentally silly to pursue an analog setup designed to optimize performance on defective records, were that possible. If you go 'lowest common denominator', then what's the point of even investing in new vinyl at all? I also agree with Viridian that there is no issue of damaging your cart playing slightly warped records. I personally have found the same thing that you have buying heavy pressings (which I do not seek out and end up with only out of necessity) regarding the high incidence of warpage. However, I find clamping to be essential not only for dealing with normal warps, but also for obtaining best sound from all records. I know Rega doesn't espouse clamping, but the platter on the 9, unlike the glass platters on their cheaper models, shouldn't be prone to excessive ringing, so I would give clamping a shot, maybe in conjunction with a Sorbothane or similar replacement mat (hey, it works on my SL-1200, and that platter sans mat rings like a bell). I would recommend a non-resonant locking clamp, such as the inexpensive Michell black delrin model I use.