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Mober Motor, Inner Platter & Bearing, Synergistic Research Record Weight & Mat 1...
First of all, deep apologies to Edmund Chan of Mober for not reviewing his products sooner. I could come up with a couple of quasi-excuses, but the real reason has been my fear of failure in installing them on my hot-rodded Linn LP12. Edmund tried to quell my fear by assuring me that there is no 'magic' in the fabled magic tweaking of the turntable. And I really shouldn't have been intimidated, given all the 'hands-on' things I tackle. (My bicycles, my motorcycle, the rain gutters on my house...) But that "Linn mystique"? I thought I had cured myself of the curse when I installed the Stack Audio products from Great Britain last year. I also thought I had taken my Linn almost as far as it could go, save for a new motor and a new tonearm to replace the Sumiko MMT that came with it back in the early 1990s. How foolish of me. There is still so much more to learn. Initially, I was hoping to install the Eagle PSU and Roadrunner tachometer from the American company, Phoenix Engineering, that went out of business a few years ago. The Hercules/Moses motor & power supply from Hong Kong seemed to be the next best bet. But before I got around to it, Edmund had come up with the more advanced Mober design I purchased for review, along with some other Mober tweaks such as a new inner platter and bearing housing. He tells me Mober offers parts for re-manufacturing an LP12 completely from scratch, except for the tonearm. He has been at this for about a decade and is committed to high-end audio, so I was comfortable taking on his products for review. For those who have not read my Tripping the Linn LP12 Fantastic review (Part 1 of the Linn Project) or the follow-up review of Stack Audio mods (Part 2), let me briefly point out that I have removed the outer ring of the LP12 platter and replaced it with a stainless steel Soundeck record mat, a weighted periphery ring and most recently, the Synergistic Research UEF Record Weight. The record mat, periphery ring, and record weight not only replace the weight lost by removing the outer Linn platter, but each makes a very significant improvement to the sound. The mods in Part 1 were all easily reversible — that is, they could be easily removed for direct comparison with the original Linn parts. Part 2 mods were installations that were not easily reversed. The gain in sound quality of the Part 2 mods was sufficiently evident that I felt no need to revert to the original Linn parts for additional comparison. Don't mess with success, as the saying goes.
Moving On To Part 3 Taking only a minute to remove the old Linn spindle/inner platter and carefully dropping in the Mober replacement is about as easy as any mod I've done to any piece of gear. I immediately heard an improvement in resolution and air as well as an improvement in pace, rhythm, and timing — either because the belt was getting a better grip on the fresh metal side of the inner platter or the bearing tip itself was new... or both. It was the best I've ever heard my Linn sound, and I dare say it sounded better than any other LP12 I've ever heard, though I have not heard one with the new Karousel bearing kit. But was it like getting an upgrade to a new, better turntable as Edmund suggested? As I thought about that I recognized I was not upgrading from a stock LP12, but from my already hot-rodded version. Before adding the Mober spindle/inner platter, my 1982 vintage turntable was only 40% original Linn parts — mostly the wood plinth, springs, bearing housing, spindle / inner platter, and the Valhalla motor and power supply. It was already pretty trick. It would be tedious to take my turntable back to stock in order to evaluate the benefit of adding just the Mober spindle/inner platter. After all, my initial impression was pretty spectacular. But to give owners of a stock LP12 a better estimate of the gain, I re-fitted the original spindle/inner platter and the original outer ring with a felt mat. Not surprisingly, it still sounded pretty good. But then, it still had all the Stack Audio parts in it — baseboard, top plate, sub-platter, and armboard, which had made their own very significant contributions in Stage 2 of this Linn project. Next, I substituted the Mober spindle/inner platter for the Linn part and kept the Linn outer ring and felt mat. As expected, it took another very pleasing step upward. The music was more enjoyable and the toe readily kept pace with the music. To someone installing their first tweak on an LP12, it probably would seem like a major upgrade or even a brand-new turntable. I can understand Edmund's enthusiasm, but I've been down this road numerous times over the past twenty years. It certainly is well worth the asking price, and I can highly recommend it, but there is still so much more music to get out of the groove. Removing the Linn outer platter and reinstalling the Soundeck mat, the periphery ring and the Synergistic Research record weight brought the performance back to the all-time high I had experienced at the outset.
Whether the very welcomed improvement afforded by the Mober bearing is due to superior machining, the ball bearing on the tip, or the inclusion of the brass insert on the inner platter, I cannot say. But I can tell you I liked what I heard and it seems to be an outstanding value at $240 plus $25 shipping. The bearing cup, which I'll get into next costs $200 plus $20 shipping, though shipping costs may come down if multiple parts are shipped together. For comparison, my friend Tom O'Keefe at Overture Audio in Ann Arbor tells me the Linn Karousel kit sells for $975 in the US and includes installation at their shop. The kit includes both the inner platter, bearing cup, a set of springs and grommets along with new nuts and washers for them and a new ground wire. At the time of this writing, Linn is also offering a free Karousel kit with the purchase of $3000 or more additional Linn products in any category. So, while there is considerable savings with the Mober parts, I think most well-heeled Linn owners will opt for the OEM parts while the inheritors of vintage machines looking to upgrade on a budget (like me), or DIY'ers will seek out the Mober alternatives. There is likely a large gap between the two camps and you already know which camp you're in.
Installing The Bearing Cup
With the tonearm locked down and the headshell and cartridge carefully removed and set far away in a safe place, I capped the Linn bearing and tipped the turntable on its left side. This allowed me to remove the Stack Audio base plate from the plinth, leaving the Valhalla power supply, mounted on the cross brace easy to access. It was easy to remove with a wrench to loosen the nuts. (The blokes in Great Britain will, of course, use a spanner.) Doing this also required unclamping the phono wires. While I was at it, I removed a web of necessary ground wires, given the 350V in the Valhalla AC power supply. The Mober uses a low voltage DC motor sourced from Maxon in Switzerland — the same company that supplied the motor to the Kronos Sparta turntable I reviewed a couple of years ago. Hence, there was no real danger or need for grounding (I thought). The cartridge would be grounded through the phono stage as is the usual practice. I later learned that the grounding scheme was one of the key features of the Linn design, though I found conflicting opinions on its benefit. I'll investigate the grounding issue further on in this review. I left the Stack sub-chassis connected to the Stack armboard with the Sumiko MMT tonearm still attached. Removing the set of the three springs that were the basis of the Linn suspension system, I then carefully pulled the sub-chassis / armboard / tonearm out through the bottom of the plinth. Removing the vintage pre-Cirkus Linn bearing housing from the sub-chassis and installing the Mober bearing housing was a matter of taking three screws out and installing the new Mober housing with the supplied screws. It is a direct replacement and everything fits perfectly. The Mober bearing housing, like the bearing housing in the new Linn Karousel Bearing Kit is much larger than the older Linn bearings, so it is not compatible with the Valhalla power supply. (The bearing housing won't fit through the hole in the Valhalla power supply or the old cross brace.) Since I was also going to install the Mober motor with its external power supply, this was not a problem — just history. Mober supplies the new metal cross brace with the bearing housing.
The tip of the Mober spindle has a ball bearing planted on it which rides on a pressed-in plate on the bottom of the housing. Two sets of ball bearings are located further up in the housing as seen in the drawing below. Edmund warns that only Linn black oil should be used in the bearing since other oils may interfere with the speed control maintaining a consistent speed. Only four drops of Linn oil are needed to cool the tip of the bearing.
After carefully threading the tonearm through the plinth and repositioning the sub-chassis / armboard, I positioned a set of new springs and rubber bushings, replacing the previous ones that were at least 28 years old. I would soon learn that this is far too long to go between replacing them with fresh springs. The bushings have been upgraded with different materials at least a couple of times in the history of the LP12, so it is wise to replace them at the same time. Linn includes a new set of springs and bushings with their new Karousel bearing kit, so obviously, they consider it important. When it came time to re-establish the famous Linn bounce, it was much easier to achieve and the platter bounced far more freely than before. This being the second time I've been through this procedure the whole process went more smoothly. And my fear? Once I got started and was focusing on the work, figuring out which step to do next, the fear disappeared. I'll admit, I had to back up and start over once, but it is not so much embarrassment as it is learning — and learning something new is a good thing, at any age.
Installing The Mober Motor The important clue is to put a towel down on your work surface to keep the small washers and screws from bouncing onto the floor if you should drop one. They're small and hard to see. Unlike the Valhalla motor, the Mober is firmly affixed to the top plate with just two screws. The two other screws for adjusting the angle of the Valhalla motor to adjust the speed are not needed. The extra hole nearest the spindle is used to secure the tachometer assembly.
The Linn belt guide near the motor is also not needed. One of its screw holes is used to align the tachometer and the other is used to feed the three thin wires coming from the Mober external power supply through the top plate to attach to the tachometer. (Brown, blue, grey, left to right.) The tachometer reads a strobe pattern that you affix to the underside of the platter. This will all be much easier to understand if you watch this YouTube video, so I won't elaborate here, except to say that a much cleaner installation is achieved if you remove the useless old Valhalla power supply. As I said above, you will need to eliminate the Valhalla power supply / motor, and instead use a new cross brace with a larger hole if you are going to install the Mober bearing housing.
The tachometer uses invisible infrared light to read the self-adhesive strobe pattern which you stick on the underside of the Linn outer platter, as I said. Except that I long ago learned this platter rings like a bell. Not good. So I replaced it with the Soundeck record mat that responds to a tap from a knuckle with a dull 'thud'. The Boston Audio Design Mat 1 also sounded quite good. Boston Audio is now under new ownership and this model has been replaced by a slightly different design that I have not tried. Either mat is sufficient to support a 200-gram record plus the 2-gram tracking force and in my application, I add 675 grams with the TT Weights periphery ring without any indication of the record bowing. Adding the extra weight to the patter beyond the outer edge of the LP also aids in maintaining a constant speed. Putting the Soundeck mat on top of the inner platter of the Linn effectively raised the bottom of the platter and hence the strobe graphic resulted in an inaccurate reading of 80-rpm record speed. Also not good. I fabricated a ring from poster board to lower the strobe graphic which helped considerably, but not dependably. Brainstorming the problem via email with Edmund over the course of a couple of days resulted in a successful solution. He is in Hong Kong, remember, and they are twelve hours ahead of New York City.
Inside the external power supply in the right rear corner is a small adjustment for the focus/range of the infrared reader. A twist of the little white dial in part VR51 with a small screwdriver and... Bingo! Not only was I able to achieve the proper speed, but I was able to remove the poster board ring. Attaching the strobe graphic directly on the Soundeck platter made for a much cleaner look. Of course, if you retain your Linn platter this should not be a problem, though you will be missing out on one of the best and most cost-effective tweaks of the project. For completeness, I reverted to the Linn outer platter and the felt mat to remind myself why I made the switch. Since I had temporarily used tape to hold the strobe ring down, I could swap platters easily.
Routing the power cable through the notch in the backside of the plinth presented a challenge because it is considerably thicker than the zip-cord used by the old Valhalla power supply. (My Linn dates back to 1982.) The new cable attaches with a five-pin connector on the back of the external power supply — two for the DC current and three small cables for the tachometer. It fills the notch on the plinth, and then some. Mober supplied a flat plate to screw into the plinth to retain the cable, but the screw heads encroached on the recess for the bottom plate. I clipped off the end of a wide, flexible plastic cable tie, drilled a couple of holes in it, and screwed it into the plinth to secure the cable. Problem solved. Knowing that I would eventually be adding a new tonearm, I refrained from doing the same with the tonearm cable. I seated the Stack Audio bottom plate into position and returned the turntable to the wall-mounted shelf. The power cable coming from the motor snapped into the power supply and I used an older Synergistic Research power cord to connect to the system's power conditioner. I was good to go.
The buttons below the LCD window are for selecting the speed — 33.3 or 45 rpm. They are solenoid buttons, not switches that click in for 'on' and click out for 'off'. They require only a light, quick touch but I found it was sometimes necessary to push them in several times before the low-torque DC motor would finally start to rotate the platter. As inconvenient as this was, it was far gentler than the routine with my old Valhalla power supply where I had to push down on the record weight and manually start the rotation with a twist of my wrist. I achieved more consistent results by adding a weight to the top of the power supply to hold it steady. Still, it would have been better with a more expensive touch switch with a better 'feel' to consistently start the platter on the first touch. I tried this without the record weight to lighten the load on the platter, but the performance did not change. The build quality is adequate but given the rock steady speed and the contribution it makes to the music, a more massive, stylish design, even if it doubled the price, would not be out of line. The two silver knobs to the right of the LCD screen were for fine-tuning the 33.3 and 45 rpm speeds in 0.1 rpm increments which were visible in the LCD readout. Given the 16 strobe marks on the ring under the platter, the microprocessor was able to make 16-speed corrections per revolution, or a correction every 0.11 seconds. Any minor speed change in that short time will not likely be audible. At least I couldn't hear any speed fluctuation. The new Linn Karousel speed controller uses a similar system, but with only one sensor mark which is read once every 1.8 seconds. How many notes would Mozart have played in 1.8 seconds? The Kronos Sparta I reviewed back in 2016 employs a similar approach as the Mober with multiple sensor points, but it is more highly refined, as well as considerably more expensive. More recently, there's a higher-tech Kronos Super Capacitor Power Supply which was reviewed earlier this year by Enjoy the Music.com's Greg Weaver. To give you a benchmark for the value of the Mober motor and power supply, this new Kronos upgraded power supply, without the motors, is $9500. A Linn Klimax LP12 turntable goes for around 18,687GBP, so upgrading to a Klimax drive will be into four serious figures no matter what the currency. For comparison, the Mober DC power supply, CPU and DC motor is $880 plus $50 shipping. To my mind, this makes the Mober motor a very high value.
With the low-torque Maxon DC motor, the platter begins to turn very slowly yet accelerates to approximately 33.3 rpm in about 15 seconds. It then goes over and under speed (33.4 to 33.2) for another roughly 25 seconds before settling in at a precise 33.3 rpm. While this may seem a bit lengthy, it enables you to relax while cueing up the record, making sure you've got the stylus over the lead groove. When the stylus is lowered and finally hits the LP, the speed drops 0.2 to 0.3 rpm because of the extra drag on the LP. Within a few seconds, it stabilizes again at 33.3 rpm. If you're already into the music by that time, you will notice a second or two of wow and flutter, but this always dissipated by the time I sat down in my listening chair. The LCD is programmed to turn off a minute after stabilizing at 33.3 rpm. If you wish to check the speed while playing at 33.3, just rotate the 45 rpm speed adjustment button slightly to activate the LCD screen again. If playing at 45 rpm, you can reactivate the LCD by slightly turning the 33.3 speed adjustment button. There are more elegant LCD read-outs but they are found in gear that is far more expensive. Once I had the 33.3 speed dialed in, I didn't have to make any additional adjustments during the several months I've been using it. Edmund tells me he has heard Maxon motors are used on the Mars rover, Curiosity. The benefit of using a DC motor is that it is much smoother than the typical AC motor with 24 poles that create slight jumps with every pole. These vibrations are transmitted through the belt to the platter and while they are minuscule, so is the environment of the stylus in the record groove. The downside of DC motors is they are very sensitive, requiring only millivolts to change speed which requires higher engineering skill and cost than your typical AC motor. Unlike the Valhalla motor it replaced, I could feel no vibration in the Swiss Maxon motor. The Maxon motor itself is a generic-looking thing, not unlike a large capacitor, but it is mounted with insulation inside a carbon fiber shell with brass end caps. It's a lot more serious looking than the Valhalla it replaced.
Periphery Ring
How It Played... Sure, there were other, smaller improvements in faster attack (but also faster decay), improved resolution, increased micro-detail, deeper soundstage with musicians a bit more firmly anchored, but there was also a loss of some bloom and the "air" seemed a bit stagnant. Record surface noise seemed to have dropped into deeper blackness on newer LPs, but the record wear on older ones became more recognizable. It was a net gain, but I also lost out on some qualities that I loved. The music was less "loosey-goosie", which is to say the timing was tighter and there seemed to be less dynamic contrast. But my toe wasn't tapping as wildly as before. It was easier to 'see' into the music, yet while the music was cognitively captivating, it wasn't grabbing me emotionally as much as it used to. Had I expected too much? It was clear the Mober was a fix that needed to be made to my slow running Linn. The Valhalla power supply also had a hum that I could hear standing several feet away from the speaker. With the Mober I could barely hear some noise with my ear two inches from the tweeter. Perhaps I had over-tweaked it to compensate for the shortcomings of the Valhalla motor and its marginal power supply? Or perhaps it needed additional tweaking to regain some of the "swing" that the music had lost?
Get Your Mojo Rising... My particular risers measure 3" x 3" x 3.5" and you don't want children throwing them around. I placed one under each front corner of the Linn plinth and one under the middle of the backside of the plinth. I needed only a penny on the back block to re-balance the turntable. Note the absence of the stock Linn feet in the photo below. The Stack Audio bottom plate had its own adjustable feet that were far superior to the hardened vintage Linn feet.
The air and bloom returned to the music and it even gained more resolution. Pushing my luck, I placed a square Soundeck footer atop each Massif block for even more air, bloom, and resolution — enough to finally get my toe tapping with enthusiasm once again and put a smile of relief on my face. Overall, the effect of adding the Massif risers and the Soundeck footers was sonically very similar to going from a box speaker to an open baffle one without any loss of bass. This was a huge win. This is a tweak you can approximate without major expense. Simply remove whatever bottom you have on your Linn and set it atop blocks cut from 2x4 lumber or pieces of 4x4. Check with your local cabinet maker to see if they might have some scrap short ends they could cut up for you at low cost. But I'll tell you, the Massif cable risers are handsome. Since my turntable sits on a wall-mounted shelf about chest high, there is little chance of it being bumped. The risers brought the platter even closer to eye level for very easy record cueing. The large footprint of the blocks plus the weight of the turntable offered sufficient security but if you live in an earthquake country you might want to consider additional modifications. I came up with a couple of 'back of an envelope' designs that could be realized by a well-equipped woodworker.
Synergistic Research UEF Record Weight & UEF Record Mat
At 33 oz. it was about 40% heavier than my reference weight, but the difference was nothing that couldn't be corrected with the suspension springs. The narrower grip at the top felt a little insecure in my fingers so I invested $10 in a lobster to get one of the grippy thick rubber bands they use to restrain the claws. The lower part of the UEF Record Weight contains a lot of technology devised during the development of their excellent Synergistic Research MiG SX footers which I recently reviewed.
I most enjoyed the openness and bloom it brought to much of the music, particularly at the top end where analog playback tends to drop off in comparison with digital formats. I'll also include improved resolution, air, depth of the soundstage, and more emotional engagement with the music. At $895 it seems very pricey, but the fit and finish are superb and you could spend a lot more money trying to achieve similar results by buying a new cartridge — particularly older gentlemen seeking better performance in the top octaves. I loaned the review sample to my audio buddy, Tom Lathrop, for a day, and he returned it in two weeks. Not long afterward he scooped up the first one to show up on Audiogon. More bloom, more air, more resolution. Are you picking up the theme?
A couple of months later I received a prototype of their new UEF Record Mat and I sent them some copy with my initial reactions.
"Close on the heels of their UEF Record Weight now comes a turntable mat comprised of a circular sheet of carbon graphite with a concentric cover of "leather alternative", both precisely die-cut. Add to that their magic UEF sauce between the layers. Having experimented with numerous mats over the years in my ongoing Linn Project I gave it a spin, placing it atop the superb Soundeck mat that replaces the outer ring of my Linn platter. As good as the Soundeck is, the SR mat improved the resolution even more, and revealing micro-details, dynamics, and tonal color that I didn't know existed on even my garage sale LPs. But the fun didn't end there. I then swapped out my reference record weight with the new Synergistic Research SX Record Weight. The music went from being interesting and revealing to full-on toe-tapping with neck-to-ankle goosebumps upon my clammy skin on a hot summer day."
Once again, I loaned the mat to Tom to play with while I turned my attention back to the Mober motor and bearing. Surprisingly, Tom came back to me with news that it didn't sound as good to him as the Herbie's Audio Lab mat he was using. I've tried numerous soft-layer mats on top of the stainless steel Soundeck platter but they've all overdamped the music. So when he returned the UEF Record Mat he brought along his mat for me to try for an hour. Having reviewed some of Herbie's isolation footers back in 2003, my expectations were low, but I was very impressed with this record mat and I'll be requesting a review sample. The point here is that different platters are constructed of different materials that will react differently with different mats. Each of us has his / her priorities of different qualities we hone in on while listening, so there is a wide range of opportunities for something to work well for you. Fortunately, with all Synergistic Research products, you have a 30-day money-back guarantee if you feel it doesn't work well for you. Of the UEF Record Mat, I will add that the carbon fiber layer, protruding 8mm beyond the vinyl pad made it somewhat difficult to lift the record off the turntable. The carbon fiber extends about 2mm further out than a so-called 12" LP, making it difficult to lift the record off the turntable while it is still spinning, if that's your usual technique. I would recommend against doing that with this mat. There's too much chance of things getting nasty with the platter in motion. The vinyl layer does lift the LP slightly higher than the carbon fiber, so it is possible to get your fingernails beneath the edge of the LP. It's just not as easy as when the LP completely overhangs the edge of a mat or platter as it does with the 292 mm Soundeck mat I use.
Grounding Rather than recreate the original Linn ground scheme I asked my friend Tom Lathrop to build up some wires using Belden mil-spec silver-plated copper 24 AWG wire that would connect directly to the Ground Block. I wired the chassis of the Mober power supply directly to the Ground Block. Inside the plinth, I wired the Mober Bearing Cup to a bolt that was also connected to the top plate. This bolt was then directly grounded to the Ground Block. The cartridge was left grounded to the phono stage via the phono cable as is standard practice. Adding the home-brew ground wires from the Mober power supply and the Linn made a noticeable, but not huge improvement to the transparency and the tonal color of the music. It was like the performers stepped closer to the mics — not so much that the music got louder, though it did seem the needle got closer to the red on the VU meters on peaks, but that the music got more real or present and less like recorded music. Given that the ground wires were connected to the passive Synergistic Research Ground Block, and that these wires were not expensive Synergistic Research purpose-built Ground Wires like I have to the preamp and other sources, the result was pretty much what I expected. It was a welcome improvement, but not of the magnitude of saying an upgrade in a power cord. One would naturally expect upgrades of that magnitude to come with more expensive active ground systems such as those from Synergistic Research or Computer Audio Design, or the star grounding system in Ansuz Acoustics power distributors — but that's an adventure for another day.
Did Someone Mention Orange Fuse?
A little more transparency and a lot more bloom making the soundscape seem more three-dimensional like real space. I like bloom, so it's a keeper. If you're not so fond of it, you have the 30-day return privilege to fall back on. It may seem a little overkill to put a $160 fuse in a motor / CPU / power supply that is $930, yet keep in mind this turntable is playing way above its price point.
Putting It In Perspective The Synergistic Research UEF Record Weight and UEF Record Mat are luxury items with the record weight opening the gates to the highest octaves. But the luxury end is where this project is taking me — into the realm of turntables costing tens of thousands of dollars. The price of all the products in Part 3 is close to $3000, but you may not need or want them all. In the world of DIY, you get to choose. Had I known that this project was going to reach such a high level of performance, I would have gladly spent the money much sooner. Like the AC Ace sports car that evolved into the Shelby Cobra, there are not many OEM parts left on this turntable. The ribbed wood plinth retains its Linn roots and pays homage to Ivor Tiefenbrun, MBE, who created the LP12, though gorgeous plinths made with other wood species are certainly available. The springs and grommets at $25 per set are available only from Linn. I'm still using an OEM belt and bearing oil, too. There is a new, higher-quality tonearm waiting for review, and a higher quality cartridge as well. These two items are usually a matter of personal choice or taste. Who knows what blacker background or musical ecstasy still lies ahead? While I'm at it maybe I should come up with a new name? How about "The Bard"?
Specifications And Manufacturers
Soundeck
Synergistic Research, Inc.
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