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What cartridge to use....Rega RB25 Structural Mod

I have a Rega RB250 with the JA Michell structural mod and Incognito rewire mounted on an Acoustic Signature Final Tool. I am currently using a Koetsu Red with very good results. I am looking for something better. Aren't we all?? As you may or may not know, the Michell mod allows use of just about any cartridge made. There are 2 different counterweights. One for cartridges with a weight of 3 to 6 grams and another for cartridges with weights from 6-13 grams. The RB250 has an effective mass of 11 grams. So, with this in mind, what do you think. I am trying to stay within the $1,000.00 range, new or used. I have some cartridges in mind. The Dynavector DRT XV-1, XX-1, XX-2, ZYX Fuji R100 FS, Benz Micro LO.4, Lyra Helikon and the Ortofon Jubilee are some of the choices thus far. I have not listened to any of the above cartridges. I am going on reviews from this site and some of the professional reviews I have read. Please let me know if you've had any experience with similar setups or if you have any recommendations/suggestions regarding other cartridges I haven't mentioned. Also, I need to purchase a cartridge alignment tool. Any suggestions on tools under $50.00 would be great!!

Thank You
Jeff
jfrizzell49

Showing 5 responses by stefanl

stefanl
296 posts
 
"Clearly idler wheels suffer from so much noise contamination that the subtleties in the music are lost, and quality cartridges and arms are a waste of time (and money)." I believe that Mr.Sugano first developed the Koetsu on a Garrard Idler Wheel Drive Turntable so he must have thought they were o.k.As regards the Rega bearings,no less a critic than Art Dudley in Stereophile has stated that they are extremely good value for the money.Here is further experience with Rega "I removed the common bearing types from a RB250, 300 and RB1000, the vertical shaft bearing are all the same size. I sent them to a precision bearing distributor and they reported they could not measure or by inspection tell any difference in grade, they all fell into the range of 1P-3P(ABEC Grade), there is some overlap." They are quite adequate and further "Two to four ten thousandths(of an inch)(ABEC Grades Referred to) is a tolerance you cannot feel. Not only that due to the arrangement of the bearings they actually reduce the radial play.
I have had literally hundreds of Rega arms (of all models) in my hands and have never had a single one with excessive play.
stefanl
296 posts
 
I am not the owner of all those arms,they probably belonged to a whole lot of people.I was actually quoting from Garth's experience with Rega arms who makes the Incognito Rewire Modification,which no doubt you are familiar with.He also states "I doubt a Rega arm would barely move with an ABEC 7P bearing which has a radial play of .0001 to .00015. I rebuilt a RB250 with ABEC 5P bearings and it was tight, very tight....I would say that the quality of tonearm assembly is of even more key importance than the type or tolerance of the bearings used."That is from someone with a lot of experience adjusting and tweaking Rega Arms and their bearings.I might suggest that you heard the Rega arm in less than ideal conditions and I would say that they are much better if tweaked from the "stock" form they are set-up on a Rega table.You would hear "smearing" in spades I am sure.I have seen the official Rega Fixture for the bearing nut and it is totally wrong.Roy Gandy probably has no right to sell his tables set-up in this way.That being said something like the Origin Live silver shows how good this arm can be,very close to a Triplanar 7 as Doug Deacon has stated on this forum.
stefanl
296 posts
 
Yes,Poaul Ladegaard in his paper on mechanical resonances in turntables established that lightweight arms are really the best performers overall.I think he used a Danish Moerch arm as one of the arms in the experiment actually.This was cognizant also on the best arm /cartridge match in terms of cartridge resonance and system matching.If you can find a good used UP-4 I would probably try it myself.I don't think Garth is misleading though and I am aware there are better arms out there.Take Mark Baker's development of the basic Rega into the Encounter arm for example.You can see what could be done to it.
stefanl
296 posts
 
I am not suprised that you preferred the Moerch and Scheu over just a rewired RB 250 because you have to do more than just a rewire.The smearing is there very noticeably until you also add a metal stub and then use TWL's amazing Tracking Weight Tweak.The control in the RB 250 then becomes feather-touch.A form of VTA adjustment is also required and then all your attention must be given to adjusting the base-nut to EXACTLY the right tension(Usually Finger-Tight with just a Nip).This is critical and quite labourious at first but the Rega literally "sings" when it comes together.Anything from cartridges as different as the old Linn Asak(MC)(Supex 1000) to the Ortofon VMS 20E Mk11(M.Iron)for example,sound great.The smeared darkness and murkiness that people notice with a Rega disappears,it is an extremely sensitive and balanced arm in reality.I guess as I don't have the urge to change now,it's doing something o.k.
stefanl
296 posts
 
"....I auditioned a Rega RB-300 vs SME V on a special Michell Gyrodec table that could accomadate two arms. Both had Koetsu Blacks mounted. We heard very little if any difference between the two arms/cartridges. The owner of this system then decided to sell the SME V and keep the Rega. Rest of system was ARC SP-9, Quad amp and Magnapan MG-III speakers." This is a post from Vinyl Asylum that seems to contradict the proposition that Rega's perform poorly with Koetsu cartridge's.Also did you actually try adjusting the Base-Nut of the Rega Arms you listened to,to the required tension?I know what an audible difference it does make,so as to eluding to what I hear as just being sorely mistaken,leads me to think that you did not explore the adjustments at this level.I think you have misconstrued what I intimated about the importance of the Rega bearings.This is my last post on this.We agree to disagree.
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