Trans-Fi Audio

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Magnetic Platter Bearing

Transfi  Salvation Magnetic Bearing Update

First of all, thank you to all that have purchased Salvation. For me its creation has been motivated by a dissatisfaction of the other turntables I have owned in the past. Since I have lived with & perfected my own Salvation over the years, there has been no other turntable I have lusted after. I hope you feel the same.

This simple modification takes Salvation to another level. Although the performance of the deck in its previous incarnation continues to be immensely rewarding, those of you that know me realise I have an innate desire to tinker, & magnets were on the agenda!

This diagram shows what the magnets do & how it completely alters the forces acting on the bearing structure:



You will notice with the magnets, there is effectively no point of contact now between the platter & plinth. The sonic benefits of this are enormous. Together with Terminator & its air cushion this means there is total decoupling of the record & stylus from the environment meaning less to colour the sound. As we all realise, the stylus is working to extract & magnify information contained in the record groove. Any spurious signals coming up from the surroundings through the plinth will also be magnified. This will normally not be heard directly, but will have an overall effect on what we are hearing, be it smearing of the sound, loss of focus & dynamics etc.

The effect of this new magnetic bearing is summarised in this mini assessment by Enjoy the Music hi-fi reviewer, Clive Meakins:

 

The first thing that hit me was the thwack of drumsticks on skin. Then I noticed a highly confident authority and speed.  Finally I spotted that sparkly treble sounds stood out better against a now incredibly silent backdrop.  The major aspects that leave a lasting impression are those of authority, scale, speed and dynamics.   Bass has the ability to be explosive and with no bloom or smearing, it's as tight as a proverbial duck's rear-end.  I can't begin to tell you how many times I've sat down to listen to one track to check how it sounds but invariably I end up listening to the whole side.  There's incredible foundation the music, the quality and scale of the bass could underpin a skyscraper.  Kick drums really KICK.  The sound is in balance right across the range characterized by tremendous dynamics, clarity and superb timing; only the very best record decks can do this.

 Having heard so much to love with my London Reference I wanted to try an MC cartridge.  I duly fitted my Transfiguration Spirit to the deck.  When comparing London Reference and Transfiguration Spirit previously I found the Reference more dynamic and open with the Spirit smooth but ultimately a tad laid back in comparison.  Bear in mind the Reference is higher priced cartridge that sets the bar high so this is no criticism of the now superseded but excellent Spirit.

 Teeing up the Spirit for the first time with the magnetic bearing revealed the same sort of improvements I heard with the Reference.  To cut to the chase, the 2 areas that stood out with the Spirit were:

 1)      The ability to hear the effect of very small setup changes, especially with regards to azimuth. 

2)      The Spirit now held its own vs the Reference in that they each did what they do well without one cartridge being noticeably better than the other.  The Reference excels at dynamics and clarity.  The Spirit excels and smoothness and flow whist achieving great authority, just as the Reference does.

With the cartridges and speakers I'm using the benefits of the magnetic bearing are very clear to hear, that's not to say the standard bearing is wanting, it's not.  It's more that a magnetic bearing provides even better isolation than any bearing with a thrust pad could ever hope to.

 One last point.  Friction?  What friction?.the platter takes over 5 minutes to come to a standstill from 33.33 rpm.  Levitating 9kg of platter is impressive and the resulting sound is really very impressive indeed.

 

Ok.....enough indulgence, let's get on with replacing the bearing.

First off, let's get the nomenclature established so you know what I'm talking about. You will also need some kind of adhesive.....superglue or silicone based.


You need to determine if your platter is a loose or tight fit on the bearing sleeve. To do this you need to remove Terminator & lift the platter off. If the sleeve easily pushes out it needs to be fixed in place so this doesn't happen.

Note: If the spindle is already a tight fit do not attempt to remove!

1.Fixing the Sleeve into the Platter

First remove the thrust plate. Blow gently through the top & it will pop out. This is not longer needed so put to one side.

The sleeve will be a tight fit, so whatever you use it won't take much....loctite, superglue, silicone will all work. Apply a thin bead to the circumference of the sleeve as shown:

A note on feedback from clients who have fitted these updates: It's probably safer to stay away from the superglue as this may set too fast. The threadlock type or silicone based adhesives will give more time. I guess I am used to the procedure so can outpace the glue!


Then push into the base of the platter rotating as you go so it spreads evenly. Make sure you press fully home ensuring the sleeve base is in contact with the underside of the platter.


2. Fitting Magnet to Platter

Next fit the thin rubber elastic ring to the base of the sleeve.


This simply acts as a spacer for the ring magnet.

Next take the magnet assembly & remove the top magnet which will have markings on it. There is a nylon ring separating the 2 magnets. Here you will experience how strong these magnets are so take care not to pinch your  fingers between them. Also, once you have them apart keep them a long way from each other. If they snap back together there is a good chance they will crack as they are very brittle!


Do a trial fit of this magnet to the platter base. The markings must be always visible. Never turn to face the platter or the magnets will attract rather than repel!


Ensure the magnet fits over the rubber ring & rests fully against the platter. Make sure the magnet has not trapped the rubber ring behind it & also is not protruding beyond the thickness of the magnet.

If this is all good, fix into place with a few drops of whatever you are using.

A note on feedback received from clients: Some have had trouble with this rubber ring either getting trapped under the magnet while fitting, or protruding so much after fitting that it fouls the bottom magnet during rotation. I will not cut these so thin in the future so it is easier to handle & can be removed once the adhesive has set.
Also suggested the superglue may set too fast.

3.Mounting Magnet to Plinth

Remove the current arrangement  from the plinth & replace with the modified one. The spindle is retained, but remove the ball which just lifts off. This is no longer needed but keep in a safe place along with the thrust plate.


Install in this sequence:

Insert  the bolt & washer from the base of the plinth.


Insert  collet/spacer & spindle from the top of the plinth


Tighten the bolt from beneath the plinth & this completes bearing assembly.


Fill the top of the spindle with oil & let it drip over the sides until the well is 1/3 full. Doesnt matter if oil overflows when platter is replaced. Better too much than too little!


Carefully lower the prepared platter onto the spindle. It should settle with approximately 1mm gap between the magnets.


Confirm platter is levitated by pushing down & watching spring back. Spin the platter & keep an eye on the platter magnet to ensure it is flat & not wobbling. If there is wobble the magnet is not resting flat on the platter & needs to be re-checked.

JOB Done! Refit Terminator, sit back & enjoy. There may be a slight height adjustment needed where the drive wheel contacts the traction belt but this will be minimal.


IMPORTANT: OIL PRIMING PROCEDURE

As the bearing has been out in the field for a while now, a few clients have had issues with dry bearings. To ensure the bearing is adequately oiled I have developed the following procedure. You will need to obtain a cheap Monojet 412 syringe. If you cant get hold of one easily (e.g., eBay/Amazon) I can send you one.

Hopefully this is a fool-proof procedure to ensure the Salvation bearing is properly oiled. You need to see oil filling the gap between the top & bottom magnets.

Using the Monojet syringe & Mobil Synthetic 30 SAE oil (or equivalent) inject the oil through the hole in the top of the spindle (ensure first you have got all the air out of the syringe by holding upright so the air rises to the top). Try to establish a seal by pushing into the hole or else the oil will go everywhere. Remove Resomat to avoid contaminating it.

As you squeeze the syringe keep an eye on the gap between the magnets. You should see this gradually filling with oil.

Every so often stop adding oil & gently push the platter down. This acts like a pump to expel the air. The bearing is flooded when oil is expelled from the top. Clean up the excess oil & run the platter. Ensure no oil is coming out of the spindle by fully depressing platter before replacing Resomat. Need to allow for oil expansion during use. Excess can be removed by tightly rolling up some tissue paper so it fits down the spindle hole or use the syringe to suck out.

This procedure will ensure oil is reaching every part of the bearing & you should not get any problems. Top up once a month.


Testimonials

MAGNETIC BEARING TESTIMONIALS

 

Christian (Switzerland)

 I just wanted to let you know that I'm really impressed by the new bearing. Unfortunately I have to admit that I first did not think that a magnetic bearing without any deduction of resonances could work. With the two new vacuum pumps (great recomendation and much better, but they need at least some boxing)  I've listened to the deck with bearing update for a couple of weeks now. After first set up I was somehow a little bothered that my deck would not reach Clives reported 5 Minute spinning from 33 1/3 rpm to 0. While setting up the tracking force of my cartrige I left my electronic balance on the platter and to my suprise it turned. I had forgotton to balance the plint carefully so I suppose that there was some friction within the bearing. Having straigtend out the plint spinning from 33 1/3 rpm takes much longer now. Somehow strange how these things can be of influence.... I never bought the deck to watch it spinning... but there you go...

 Good news is that there is also a severe improvement when it comes to sound. My first impression was that the ammount of groove noise is reduced to a minimum. Not that this was an issue with the conventional bearing but I think one will notice the difference immediately. Sound stage turned out to be more precise. It was broad and deep with the conventional bearing as well but with the bearing update there is more headroom or quietness between the instruments. This leeds to even better transparancy, dynamics and attac. Especially small signal reproduction benefits from the update. Timbre and timing is rock solid. I'm really suprised and I wonder to which level the deck can be taken with future updates...;-)))

 

 

Frank (UK)

 Well, just as I think vinyl replay with the Terminator / Salvation combination cannot get much better, you prove me wrong with every upgrade! The improvement is massive! Rather than go into too much detail, I think I can summarise as follows:

I consider that the overall improvement results from elimination of mechanical noise from a bearing / thrust plate assembly which results in reduced smearing of information. The reduction in background noise level is stunning bringing with it a clearer more relaxed natural sound yet having improved detail, timing, transient attack and 3D spatiality. Fantastic!

 

 

Alan (USA)

Well the new magnetic bearing is a clear and unmistakable improvement. The sound has more swing (prat), bass is firmer, information across all frequencies is clearer, instruments more distinct, soundstage wider. Large dynamics and percussive effects are more and more naturally pronounced. One unusual and unexpected improvement: sudden transient bursts (dynamics) in the 3-5khz range have tended to be a bit hard/bright/too vivid on my system and in my room. But after changing the bearing, not so much. Also, one a few records the entire sound is different ( positively that is): instruments are much more distinct, the vocal more lifelike, the soundstage very different than before the change.

 

 

 

Ray (UK)

 Hi Vic,

 Ray put his turntable back together- fairly quickly, but he?s quite adept at setting up the T3 by now- and we had a listen to the magnetically levitated bearing mod. No possibility of a direct before and after comparison, but of course Ray knows his system and music very well. The consensus was that the sound was better in several ways. Bass seemed to have better definition and texture- it was easier to hear what was being played on bass and drums for example, and the character of instruments was more apparent. Bass power and impact seemed slightly improved. Stereo seemed better focussed but at the same time scale, including a sense of image depth, seemed greater. Ray?s general impression was a cleaner ?less grainy? sound. My impression was similar, that the sound was less like a mechanical reproduction and had more of the ease of real music. Treble seemed better to me too- subtle changes in stick and brush work on cymbals was more obvious, in terms of technique and dynamics. Dynamics seemed better across the board in fact. I was more aware than I usually am with recorded sound how dynamics were being used expressively by the musicians. As usual with descriptions of differences, this tends to read as if the improvements were profound, but of course the sound was already very good, so these changes are incremental, not revelatory. I thought it was a significant step forward though. No voodoo, just the effect of less noise being read by the stylus to interfere with the music. Thanks again from Ray and me for a very worthwhile upgrade and I look forward to hearing my deck with the mod- when I finally get it set up!

 All the best,

 John.

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Magnetic Feet

Salvation Magnetic feet Update Sept 2014
 
Testimonial from client:
 
 .......... after extended listening I would say definitively that the magnetic feet
provide a major benefit.

What I heard consistently was deeper bass (I also was able to measure this in my
room, pre and post magnetic feet--clearly a few db more output 25-60hz), more
propulsive dynamics, greater instrument separation, lower noise floor. The bass
foundation of music was hugely helped by the feet and generally music is more
effortless.

I didn't think that these feet would provide this kind of benefit, as my table
was already well isolated, so I think that whatever one's table set-up, adding

these feet will be a major benefit--as long as the rest of the system will allow
it to be heard.
 
 
 
Having successfully converted the platter bearing to run magnetically I turned my attention to see if something similar could be done with the supporting plinth feet. It turned out to be fairly simple retaining the existing Aluminium collets & finding appropriate magnets. This consisted of a pair of opposing rare earth ring magnets, one housed in the top collet & one in the bottom. The top magnet was designed to fit on a cylindrical delrin carrier with captive thread to allow for height adjustment. This is done by simply turning clockwise to raise the height (viewed from top) & anticlockwise to lower.

With the magnetic platter the level is absolutely critical & this will be discussed at the end on setting up.

The plinth will be dispatched with the top aluminium collet already bonded to the slate plinth & the delrin carrier/magnet fitted.

Note: If you are updating a standard Salvation to the new magnetic feet, the black cylinders carrying the top magnets will need to be fitted to the upper plinth collets. The existing
fitting will need to be replaced & discarded. The front cylinders carry one magnet, the rear 2.

 
The bottom collets are separate & it is assumed you already have a level platform for Salvation to sit on. Also please realise with these feet, lifting Salvation & moving is not possible without going through this whole procedure again.....you will soon see why!

This pic shows the 3 feet the plinth must be lifted into. The 2 front ones are identical but the rear one contains more magnets as the rear has to do more work. Please identify which one this is, but it will come labelled.

It is also suggested to proceed with the platter already fitted as per original instructions. The weight of the platter will help to seat the magnetic feet. At this stage the turntable should therefore be sitting on its delrin carriers on its dedicated platform with the platter fitted.


Should also be mentioned to keep the feet away from each other & clear any iron tools/objects from the vicinity. The magnets are extremely powerful & also brittle.

Starting on the front feet, one at a time, lift the corner of the plinth enough to allow the bottom collet to be placed underneath it. As you bring the top & bottom sections together you will feel resistance as the magnets repel. Fight against this & force the top into the bottom. Once located it will be stable within the collet lip.

The following sequence of pics illustrates:



Do the same for the other side.

The 2 front fit should now be fitted & stable. Its now a question of lifting the rear & inserting the last foot. Procedure is the same as the front 2:




If you find the front feet have a tendancy to lift off,  support with chest/stomach or engage the assistance of a second person.


All feet are now engaged. The turntable can be gently slid into its final position with the feet engaged.

Test the magnetic suspension by pressing down on the corners. Should be a couple of millimeters free play.

Now mount the Terminator using is appropriate slot shown below:

.....and tighten to the plinth ensuring space is maintained between mounting column & platter edge:


Finally, level the plinth using the bubble provided & spacer to position over the platter spindle:


As mentioned earlier, height adjustment is achieved by rotating the delrin cylinder in the upper collet  by simply turning clockwise to raise the height (viewed from top) & anticlockwise to lower.

Refer back to the original manual for more detailed info on levelling.