SME - 3012 Tonearm variations Mk1 Mk2 & R

[WESTLOWER]

Great info and very interesting link....

[tlscapital]

Yes, understanding that the wand/tube and knife edge bearing material match is more significant/determining than just the singular arm material build. There the knife edge bearing is really revealing this SME design's peculiar sonic signature.

Love it or hate it, it's not everyone idea of what bearing should be. At first I was also a bit weary of my SME wobbly bearing... Yet I have learn to truly love and appreciate it. Even more so after having studied it's inner anatomy from close. Simple and effective.

Finally I have find that such well manufactured bearing truly benefit sonically from heavy effective mass/inertia. Originally the heavier mass SME's are the 3012 and they get the favor for most for their better tracking ability and heavier effective mass.

Since I had the chance (somehow) to get a not so desirable (=not sacred) SME3009 'Improved' SII (roughly tweaked prior) that I could only improve, I progressively convert it into a very heavy effective mass to suit my low compliant cartridge.

This truly revealed my SME sonic signature at it's best.

[Barry]

I prefer the 'Improved' arm's method of decoupling the counterweight assembly from the arm tube. Using an outrigger arm to equalise the force on the two knife edge bearings means that there is always a clockwise (as viewed from the cartridge end) torque imposed on the rubber bush, which with time will perish and the assembly sag, if not completely collapse. I have had this happen on two of my 3009s, and whilst replacement bushes are readily available, the removal of the old one can be very difficult (as they were glued in place). Sadly SME are no longer willing to service 3000 series arms, regardless of type. Fortunately though Johnnie (or 'J7') at Audio Origami can provided a quick, efficient and reasonably priced service in this regard.

The decoupling used on the 'Improved' arms means that if, and when, the four rubber grommets perish, the counterweight won't sag or collapse.

[tlscapital]

I prefer the 'Improved' arm's method of decoupling the counterweight assembly from the arm tube... ...The decoupling used on the 'Improved' arms means that if, and when, the four rubber grommets perish, the counterweight won't sag or collapse.

me too ! Thought to keep this to myself only, as a little "guilty secret". Expecting to expose such a trivial preference would raise a wave of protest

Seriously, it work pretty good for me as it also allowed me to simply fit my heavy and later heavier "tailor made" counterweight with ease and elegance.

Still I intend one day to seek other "fixings" for the 'spider web' 3 points and grommets assembly as indeed it tends to "fall down" with my heavier counter weights...

[Barry]

Agreed, the use of heavier counterweights (for use with Ortofon SPUs for example) is a bonus. But your heavier counerweight must be very heavy for the decoupling to sag.

I have a spare spider (and yes you're right: there are three grommets, not four), which I was thinking of using on an SME3012. But despite being the 'shallow' version as used on early 'Improved' arms that used the long knife-edge bearing block, fitting it to the arm tube of a 3012 would require some surgery; something that is beyond my abilities. No doubt Audio Origami could do it for me if I asked.

[tlscapital]

Agreed, the use of heavier counterweights (for use with Ortofon SPUs for example) is a bonus. But your heavier counerweight must be very heavy for the decoupling to sag.

Some 8 years ago, I was advised to buy me a Denon DL-102 MONO cartridge to suit better most of my sixties and seventies records (45's mainly), most which are MONO, not all. But I did not know those 'compliance' factors and other indeep pre-amplifications specifications about cartridges. I was lend a Thorens with a SME tonearm. That we fitted the Denon DL-102 on. Convinced that this was already a better sounding performer than my Technics SL1200 and Shure 'White Label' combo, I converted. The original SME counter weight was pulled back to the max with the VTF at 2.5 grams then... And it started to sag since more and more...

It's only 2 years later, after browsing on the net, that I understood that I had a SME3009 'Improved' SII version (the lightest of the SME3009's) and that more effective mass should benefit better my low compliant DL-102 fort whom no manufacturer's compliance specs are given !!! But believe me it's low of the lowest. By ear it truly benefited. Showing gradually a better focus, clarity, depth and precision. Since I could only go into my tweaks in conversion step-by-step, I had more time then than money at that time, I had to do it all DIY over months to evaluate them individually while selling on the spare original parts to fund the replacement ones.

Last I got myself a 160 grams heavy 'tailor made' counterweight ! I had it done by an English craft men to have the necessary precision in balance. That mass enhancement is the last I did after doing some test. Went the opposite way of 'modern' build and opted for a lengthy counterweight in 'teardrop' shape (echoing both the MKII SME3009/12 pivot pointed bearing top/enclosure and the Thorens TD160 speed changer) with the extra weight in the the tail's end of the counterweight. This required to add mass on the headshell/tonearm mounting connector (Ortofon) collar and the replacement with a heavier 'rider' and 'bias' weight altogether...

I have a spare spider (and yes you're right: there are three grommets, not four), which I was thinking of using on an SME3012. But despite being the 'shallow' version as used on early 'Improved' arms that used the long knife-edge bearing block, fitting it to the arm tube of a 3012 would require some surgery; something that is beyond my abilities. No doubt Audio Origami could do it for me if I asked.

I hear. And indeed to fiddle cut and drill on the SME tube/wand tail, is something I would need to feel fully equipped gear wise with to work on. That which I am not in the first place. Yet that sounds like an interesting project IMO. Something to sleep on definitely.

[Barry]

Since the rear screw fixing of the knife-edge bearing block on the pre-Improved arms is further away from the junction of the main arm tube with the counterweight stub, I suppose one could simply drill a new hole to fit the spider. But I would prefer to fit the spider in the exact same way as was done on the 'Improved' arms: the spider is held captive using the rear screw of the bearing block. To do this would of course require the arm tube to be shortened - something that is beyond my ability to do a neat and precise job.

Maybe I will discuss the project with Audio Origami. I would also need a new counterwight stub with a threaded end made up, so I could use the existing counterweight: heavy versions of the 'Improved' counterweights are difficult to find.

[tlscapital]

Please keep us posted if ever you do that very transformation. Rather interesting I find. For your information; the rider and anti-skate weights had to follow my new heavier effective mass tonearm whole balance with my the addition of my first heavier compatible counter weight... And with my second massive 'tailor made' counterweight, I even had to purchase new heavier rider and bias weight to allow to set and sit properly the tonearm.

p.s.: I have PM'ed you on a heavier SME 'Improved' compatible counterweight matter.

[WESTLOWER]

SME Geometry
is there a definitive on which alignment the SME 3012 mk2 or SME 3012r were designed for?

[WESTLOWER]

Can anyone shed light on this?