LP 12 and Mark Kelly's Board

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Hi,

I am currently in the process of refurbishing an old LP12. It has an original Valhalla board and very tired motor. I wondering if it would be possible or even wise to switch out the board and motor with Mark Kelly's 2.0 PCB controller board and associated Maxon motor.
I have Mark Kelly's PCB and motor as i took part in an old group buy but never got around to stuffing the boards.
The linn platter is approx the same size as anything else that i would have used and as long as i use the pulley that was designed for the Kelly PCB i should be at least within the correct range?
Any thoughts or warnings?
Cheers
 
Are you sure it's the motor, usually the Valhalla is the one who gets tired first.

Were you going to adapt the Maxon motor to the LP12, or use the platter/sub-platter/bearing from the Linn and build something else?
Sorry, I'm not familiar with the 2.0 PCB controller/motor. Is it DC?

Didn't you have a Pass Pearl for sale a while back?

Jeff
 
I am planning on using the LP12 chassis, bearing, platter and sub platter with Marks controller and DC motor.
I have done a bit of research and it appears that a company sells a motor kit that is basically a DC motor with controller for the LP12. It might take a bit of fiddling with the dip switches but i see no reason why Marks parts can stand in place of these:
http://www.turntable-power-supply.com/turntables_fitting/linn_lp12_fitting.htm
http://www.turntable-power-supply.com/index.htm

I landed up donating the Pearl to Burning amp. I believe the proceeds went back to DIY audio
 
Sounds like the mod should be pretty straight forward. As long as the motor/pulley speed is correct, everything else is just mechanical.

You could build a nice box for the PCB similar to the Origin Live unit with appropriate switches etc.

I've never heard an LP12 with the Origin Live DC kit, but reviews are mostly positive.

Jeff
 
Finally finished installing the LP12 with Marks' DC controller and Maxon motor. Smooth, clean and dead stable
 

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In all honesty i have nothing even close to compare it to. It replaced a Rega P3 with plex platter and Elys cartridge. The Linn runs with a Denon DL103 cartridge.
To my ears the Linn smokes the Rega set up. There is more authority in the base and far more separation across the spectrum. But the mids is were it really shines. PLaying Cat Power is breathtaking.
I do have a couple of questions though:
1. The feet on the turntable are currently three spikes, which i did mostly for leveling purposes. What might I expect to happen if i replaced the spikes with rubber feet?

Thanks
Neil
 
Your mind operates differently to mine :) I would never consider going through all this effort if i don't have a good LP12 at hand as a reference. The majority of LP12 owners use it with an Ittok/Valhalla and generally complain about bass bloat and poor dynamics. Would have been interesting to know if the the dc motor resolves this.

Sorry, no opinion about spiked feet. I always used mine on a ultralight table and without the bottom cover.
 
neil_kaye said:
The feet on the turntable are currently three spikes, which i did mostly for leveling purposes. What might I expect to happen if i replaced the spikes with rubber feet?

Could depend on what your table is sitting on. Going to rubber feet could be like installing a Trampolin. I bought one ages ago but never installed it after reading so many negative experiences from other users. I'm still using black diamond cones that came with my table.

Nice work on the conversion BTW. May I ask why you decided to install the goodies in the table and not outboard?

Jeff
 
For better or for worse I am generally of the opinion "why use two boxes if you can use one".
It was also a bit of a cost issue; if i factored in the cost of an aluminum chassis with custom face plate and anodized, the project seemed less worth while.
I do not believe i am getting any electronic interference from the components, and call me nieve but since it has a suspended chassis design i was not convinced that adding a little extra weight to the chassis was going to make all that much difference.
The weight of the cells is small when compared to the platter
 
analog_sa said:
I also know someone who placed his Valhalla externally and swears it made a big difference. Audiophilia nervosa?

I did this as well, but I wouldn't say it made a BIG difference. It was subtle but definitely audible. I also did the top plate flip and coated the underside of the sub-chassis with Silent Running SR1000 anti-vibration compound. These three mods together made a BIG difference.

Jeff
 
Neil,

Are you using the linn belt with the tape pulley? I just a motor and board to do exactly what you did.

I replaced the 4 bottom bumpers on my LP12 with 3 rubber feet salvaged from an old Rega 2. I didn't hear a difference and it made the TT look funny so I just put the stock feet back on.

With respect to Linn mods, an external Valhalla did seem to tighten things up a bit. Other things that helped on my LP12:
Remove the bottom, I don't know whether having the mass of the controller and battery on your TT would have a similar effect.
Replace the tiny screws connecting the subchasis to the armboard with larger screws.
Do the LP12 "bolt mod" if yours doesn't already have in.
 
Originally posted by summilux I replaced the 4 bottom bumpers on my LP12 with 3 rubber feet salvaged from an old Rega 2. I didn't hear a difference and it made the TT look funny so I just put the stock feet back on.

A way around this is to glue or screw blocks under the corner braces. If you put threaded inserts in the blocks, you can use any type of foot that has a threaded shaft.

Originally posted by summilux
Remove the bottom, I don't know whether having the mass of the controller and battery on your TT would have a similar effect.

Many believe the cheap press-board bottom acts like a drum.

Jeff
 
The base on my modification is 1/2" MDF CNC milled to accept the motor controller and batteries. It is definitely more rigid than the stock Linn masonite base.

The belt is a square shaped 1mm x 1mm. I landed up using a pulley from an earlier group buy with a v-section that accommodates this OEM pulley perfectly. I tried using a Teres pulley with the Linn belt but I had to much drift of the belt on the subchassis. My current solution seems to work well with so far very good speed stability. Of course this could change once the belt begins to deteriorate and stretch. If anyone is interested in this approach i can dig through my records to find the company that i purchased it from. Come to think of it i should order some more to have a few spares.
 
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