The Mike New Bearing Base Plate

[Audio Al]

especially one with short arms.

And short legs

[worrasf]

I'll have you know my legs are perfectly proportioned

[Audio Al]

I'll have you know my legs are perfectly proportioned

Opps !

Thought we were referring to our leader

[Ammonite Audio]

I have had my MN bearing a goodly while and am more than happy with how much it has improved the SQ over the stock and Vantage bearing. I have angsted over the base plate as I can totally see how it would improve SQ still further but I just don't want the platter lifted higher (Funk and bonded achromat) and if I'm honest didn't want to shell out any more dollar. So, after much thought and trepidation I decided I would permanently bond the bearing to the chassis thereby realizing the sonic benefits of improved structural rigidity. This is not for the timid as it is irreversible but having done it I can report definite improvement in low level detail (especially instruments "well back in the mix") and tighter, deeper bass - plucked double bass in particular.

I wanted to take the deck down to remove the pitch control as I've just bought a new top plate with no cut outs for the pitch control or 45rpm adapter so this was the ideal opportunity to "do the bearing"

Having totally dismantled the deck and removed the bearing I thoroughly cleaned the bearing case and the bearing well with acetone before pouring 25ml (20ml would be better I think) of mixed fibre glass resin into the bearing well. This has about 5 minutes of working time and sets in 20 minutes so you need to be nifty. Having partially filled the well I then gently placed the MN bearing into the resin and secured as usual with the 3 motor bolts and PCB screws - you need to fit the PCB because there is a deal of play in the bearing with just the 3 bolts. The bearing will displace some resin out of the well which will fill the void between the undersurface of the bearing and the chassis which results from the 3 proud mounting lugs. All the bolts and PCB screws were fully tightened and the assembly left for 60 minutes for the resin to fully harden.

There is no going back after this! If you FUBAR the deck is scrap!! There is no way to remove the bearing. Like as not you will also find that the 3 bolts will be fixed solid as a bit if resin will find its way into the threads even if like me you remove, clean and reinsert them. However, this is not FUBAR because if you do need to remove the PCB in future you can drill out the bolt heads and slip the PCB off and then (probably) remove the bolts with a mole grip.

Having reassembled the motor fired up no problem ( phew) and the improvement in timing and detail and bass was instantly obvious. So this "tweak" worked out very well but as I say does have the potential to seriously spoil your day if you get it wrong.

As a bonus having removed the pitch control I connected the earth wire that was previously attached to it and the arm board so that the arm board was earthed direct to the PCB earth screw instead - this totally removed the little bit of hum I was getting previously since installing the Croft MC headamp. previously with no music playing there would be audible hum with the volume pots above about 5, now I can wind them right up with no hum at all!

So all in all a very worthwhile few hours

Not attached and piccies as there really isn't anything to show

I would have used beeswax instead - it's still used for temporary mounting of accelerometers since its vibration transmission characteristics are rather good.

[worrasf]

I would have used beeswax instead - it's still used for temporary mounting of accelerometers since its vibration transmission characteristics are rather good.

Before this intervention I used the KAB thrust plate support wax which is very similar to the bees wax. As I posted previously it did indeed improve over no support but the "resin bonded" solution resulted in a significant improvement over the KAB wax. The main areas are in low level detail retrieval and improved timing

[worrasf]

Indeed, Mike - and quite simply, it allows the bearing itself to perform to its full sonic potential. I was shocked and stunned at just how much more ‘grown up’, weighty and purposeful sounding my SL-1210 was after fitting the BBP, having up until then used one of your bearings (and loved it), but not realising *just* how good things could get!!

Marco.

Having listened to the deck a few hours this morning with the "bonded bearing" I am astounded just how much better all music genres are sounding now. It's not just the bass that benefits. There is a tangible improvement in grip and timing across all frequencies resulting in a more lifelike and natural presentation - these improvements are not subtle IMO.

I would hesitate to say ( but I will) that the improvement is so great due to the greater rigidity and stability of the bearing that anyone considering a MN bearing should give serious consideration to getting a base plate at the same time and have done with it.

Because of the irreversible nature of the way I have mounted my bearing I would not suggest this is a route many would want to follow and would support Mike's view that the base plate is the preferred option but I can categorically say that my "bonded bearing" solution gives a significant improvement in SQ - actually it's remarkable how much better it is.

Steve

[Wakefield Turntables]

Having listened to the deck a few hours this morning with the "bonded bearing" I am astounded just how much better all music genres are sounding now. It's not just the bass that benefits. There is a tangible improvement in grip and timing across all frequencies resulting in a more lifelike and natural presentation - these improvements are not subtle IMO.

I would hesitate to say ( but I will) that the improvement is so great due to the greater rigidity and stability of the bearing that anyone considering a MN bearing should give serious consideration to getting a base plate at the same time and have done with it.

Because of the irreversible nature of the way I have mounted my bearing I would not suggest this is a route many would want to follow and would support Mike's view that the base plate is the preferred option but I can categorically say that my "bonded bearing" solution gives a significant improvement in SQ - actually it's remarkable how much better it is.

Steve

Steve,

I did this mod years ago and have never looked back. Welcome to the club.

[worrasf]

Steve,

I did this mod years ago and have never looked back. Welcome to the club.

Outstanding!
Glad I'm not just guilty of "emperors new clothes" syndrome.
Did you use liquid resin like I did or epoxy?

[CageyH]

Would wax not do the same thing, with the added advantage of being able to be removed?

[worrasf]

Would wax not do the same thing, with the added advantage of being able to be removed?

Nope! See post 115 above for my experiences with both