Jump to content

Sign in to follow this  
unclemack

Is there a TT bearing expert in Vic? the Luxman beckons..

Recommended Posts

Hi all,

 

I'm thinking of taking another run at fixing my PD 350. The TT has so far had pretty much every electronic component changed including caps and all controller ICs. Stuart from SGR spent many hours working on this and could not fix the speed issue... the Ghost in the Machine.

 

After all that time, Stuart concluded that the likely cause is in the bearing. After running for an hour or several hours at correct speed, (depending on the environmental temperature), the platter picks up speed and races along spinning very quickly. It seems that the bearing might be heating up the electronics responsible for speed control somehow causing the speed anomaly after warm up time has elapsed.

 

Now I need to have someone diagnose what my bearing is doing and how it is causing this heat/friction so a fix can be applied...

 

I know you're probably all sick of hearing about this freaking Luxman but, everytime I look at it sitting idle...well, I just can't give up on it.

 

So, is there somone who knows this stuff...who is the bearing king?

 

Cheers

 

M

Share this post


Link to post
Share on other sites

 

 

I know you're probably all sick of hearing about this freaking Luxman 

 

 

Pigs arse.

Share this post


Link to post
Share on other sites

Hi all,

 

I'm thinking of taking another run at fixing my PD 350. The TT has so far had pretty much every electronic component changed including caps and all controller ICs. Stuart from SGR spent many hours working on this and could not fix the speed issue... the Ghost in the Machine.

 

Cheers

 

M

 

So Stuart spent "many hours" working on this ... did he charge you for his time?

 

If he didn't ... you're a very lucky man! ;)

 

If he did ... I suggest you've already spent more than the TT is worth - with the need to spend more, to fix the problem.

 

So why not put this further expenditure towards a "decent" TT - that actually works - and give the Luxman to a cash-strapped vinyl enthusiast who likes fixing things? :)  That way you:

  1. get some karma points, and
  2. get to enjoy your listening to vinyl!

 

 

Regards,

 

Andy

Edited by andyr

Share this post


Link to post
Share on other sites


Bad luck M. I can't recommend anyone but I have a couple of questions:

Have the speed adjusting pots been replaced?

Does this thing have a strobe light?

Is the speed unstable with and without the vacuum hold down on?

Is the speed unstable on both 33 and 45 speeds?

What belt are you using?

Edited by Telecine

Share this post


Link to post
Share on other sites

So Stuart spent "many hours" working on this ... did he charge you for his time?

 

If he didn't ... you're a very lucky man! ;)

 

If he did ... I suggest you've already spent more than the TT is worth - with the need to spend more, to fix the problem.

 

So why not put this further expenditure towards a "decent" TT - that actually works - and give the Luxman to a cash-strapped vinyl enthusiast who likes fixing things? :)  That way you:

  1. get some karma points, and
  2. get to enjoy your listening to vinyl!

 

 

Regards,

 

Andy

Andy,

 

I have a "decent" turntable atm. I purchased an Acoustic Signature Challenger TT and am enjoying it very much. So, I am enjoying vinyl once again. Is this worth pursuing? I have no idea and I suspect that I am being ruled by my heart on this rather than my head. The Challenger works beautifully but is a sterile looking piece of equipment. the Luxman is simply a gorgeous TT, more a gorgeous boat-anchor at this point I guess, but when it works, its hard to beat both from a sonic and aesthetic viewpoint.

 

I find it hard to fathom that there is no-one that can inspect a bearing and diagnose whether it's at fault in any way...

 

Cheers

M

Share this post


Link to post
Share on other sites
Guest JohnA

So Stuart spent "many hours" working on this ... did he charge you for his time?

 

If he didn't ... you're a very lucky man! ;)

 

If he did ... I suggest you've already spent more than the TT is worth - with the need to spend more, to fix the problem.

 

So why not put this further expenditure towards a "decent" TT - that actually works - and give the Luxman to a cash-strapped vinyl enthusiast who likes fixing things? :)  That way you:

  1. get some karma points, and
  2. get to enjoy your listening to vinyl!

 

 

Regards,

 

Andy

 

he does have a very nice acoustic signature turntable, and can understand why he wants to keep the luxman.

 

M, as Turantable said, contact Duc (Lovetube).

Share this post


Link to post
Share on other sites


Bad luck M. I can't recommend anyone but I have a couple of questions:

Have the speed adjusting pots been replaced? No but they have been checked and ruled out as a cause.

Does this thing have a strobe light? No

Is the speed unstable with and without the vacuum hold down on? Yes

Is the speed unstable on both 33 and 45 speeds? Yes

What belt are you using? I think it's the original belt. it's the one that came with the TT.

Thanks Telecine...

 

Cheers

 

M

Share this post


Link to post
Share on other sites

he does have a very nice acoustic signature turntable, and can understand why he wants to keep the luxman.

 

M, as Turantable said, contact Duc (Lovetube).

2 for Duc....

 

Thanks John and TT, I'll give it a shot.

 

Cheers

 

M

Share this post


Link to post
Share on other sites

Andy,

 

I have a "decent" turntable atm. I purchased an Acoustic Signature Challenger TT and am enjoying it very much. So, I am enjoying vinyl once again. Is this worth pursuing? I have no idea and I suspect that I am being ruled by my heart on this rather than my head. The Challenger works beautifully but is a sterile looking piece of equipment. the Luxman is simply a gorgeous TT, more a gorgeous boat-anchor at this point I guess, but when it works, its hard to beat both from a sonic and aesthetic viewpoint.

 

I find it hard to fathom that there is no-one that can inspect a bearing and diagnose whether it's at fault in any way...

 

Cheers

M

 

 

I guess if I had to sum up why I persist with the Luxman...

 

Sorry, UM - I had no idea your Luxman was such a top TT when it was released.  Or that you had another good TT as well.  :sorry:

 

In terms of aesthetics - yes, I agree the Luxman is more attractive than the "thing" in the RHS pic ... but it still doesn't exactly float my boat. ;)

 

BTW, if you compare the listening experience from the Acoustic Signature Challenger vs. the Luxman (when it's working properly, before it starts racing), which gives you the more pleasure?  By which I basically mean ... which TT communicates the emotion in the singer's voice better than the other?

 

Re. your complaint that it can't be too hard to inspect a bearing, to see if there's anything wrong with it ... without wanting to contradict Stuart (because he is da Man! :D ), as I had a similar speed problem with my LP12 recently - which turned out to be the Lingo speed controller - I would've thought it is more likely there is a something wrong with your Luxman motor controller, rather than the bearing.  (My problem resulted in the Lingo needing to go back to Scotland, for a compete overhaul! :( )

 

 

Regards,

 

Andy

Edited by andyr

Share this post


Link to post
Share on other sites


Sorry, UM - I had no idea your Luxman was such a top TT when it was released.  Or that you had another good TT as well.  :sorry:

 

In terms of aesthetics - yes, I agree the Luxman is more attractive than the "thing" in the RHS pic ... but it still doesn't exactly float my boat. ;)

 

BTW, if you compare the listening experience from the Acoustic Signature Challenger vs. the Luxman (when it's working properly, before it starts racing), which gives you the more pleasure?  By which I basically mean ... which TT communicates the emotion in the singer's voice better than the other?

 

Re. your complaint that it can't be too hard to inspect a bearing, to see if there's anything wrong with it ... without wanting to contradict Stuart (because he is da Man! :D ), as I had a similar speed problem with my LP12 recently - which turned out to be the Lingo speed controller - I would've thought it is more likely there is a something wrong with your Luxman motor controller, rather than the bearing.  (My problem resulted in the Lingo needing to go back to Scotland, for a compete overhaul! :( )

 

 

Regards,

 

Andy

Hi Andy,

 

If you mean the speed control ICs then they have been replaced with new ones bought from Germany and the US. The speed adjustment pots have been checked and cleaned and found not to be at fault. I think the bearing theory is reasonably sound as the TT works fine until it heats up and it's likely that the heat is coming from a mechanical source which is, in turn, causing an electronic malfunction. Again, it's all about proper diagnosis and this is why I am looking for someone who can conclusively determine if and why the bearing is not functioning correctly... 

 

Cheers

 

M

Share this post


Link to post
Share on other sites

Hi Andy,

 

If you mean the speed control ICs then they have been replaced with new ones bought from Germany and the US. The speed adjustment pots have been checked and cleaned and found not to be at fault. I think the bearing theory is reasonably sound as the TT works fine until it heats up and it's likely that the heat is coming from a mechanical source which is, in turn, causing an electronic malfunction. Again, it's all about proper diagnosis and this is why I am looking for someone who can conclusively determine if and why the bearing is not functioning correctly... 

 

Cheers

 

M

 

Hi UM,

 

By "speed controller" I mean the totality of the electronics driving the motor.  In my case, with the LP12, this is an external box - the Lingo.  My problem could've been caused by something heating up (a resistor?) and affecting some other component in the circuit.  I have no idea; it was intermittent and the local Linn dealer first of all said there was nothing wrong with the Lingo - luckily, he then tried it again the next day and "found" what I had told him was the problem! ;)

 

It seems to me that if the bearing itself was heating up - you said after a few hours - then:

  1. I find it hard to see how this would, in turn, heat up speed-control circuit components (and cause an electrical malfunction) ... unless in the Luxman, they are tightly packed around the bearing?
  2. The heat in the bearing would surely have a negative effect on it - so it would no longer run smooth?

Can you remove the speed control components from the plinth into an external box (like many TTs have! ;) ) so bearing heat can be discounted?

 

 

Regards,

 

Andy

Share this post


Link to post
Share on other sites

Hi UM,

 

By "speed controller" I mean the totality of the electronics driving the motor.  In my case, with the LP12, this is an external box - the Lingo.  My problem could've been caused by something heating up (a resistor?) and affecting some other component in the circuit.  I have no idea; it was intermittent and the local Linn dealer first of all said there was nothing wrong with the Lingo - luckily, he then tried it again the next day and "found" what I had told him was the problem! ;)

 

It seems to me that if the bearing itself was heating up - you said after a few hours - then:

  1. I find it hard to see how this would, in turn, heat up speed-control circuit components (and cause an electrical malfunction) ... unless in the Luxman, they are tightly packed around the bearing? Yeah. I believe that the affected components are in reasonably close proximity to the bearing housing.
  2. The heat in the bearing would surely have a negative effect on it - so it would no longer run smooth? Maybe, maybe not. That's where an expert is needed.

Can you remove the speed control components from the plinth into an external box (like many TTs have! ;) ) so bearing heat can be discounted? Many TT's now maybe but back in '77 it wasn't as common I guess. 

 

Regards,

 

Andy

Share this post


Link to post
Share on other sites

A turntable bearing heating up enough to affect speed control electronics? You are living in la la land.

ron

Share this post


Link to post
Share on other sites


 

Hi UM,

 

By "speed controller" I mean the totality of the electronics driving the motor.  In my case, with the LP12, this is an external box - the Lingo.  My problem could've been caused by something heating up (a resistor?) and affecting some other component in the circuit.  I have no idea; it was intermittent and the local Linn dealer first of all said there was nothing wrong with the Lingo - luckily, he then tried it again the next day and "found" what I had told him was the problem! ;)

 

It seems to me that if the bearing itself was heating up - you said after a few hours - then:

  1. I find it hard to see how this would, in turn, heat up speed-control circuit components (and cause an electrical malfunction) ... unless in the Luxman, they are tightly packed around the bearing? Yeah. I believe that the affected components are in reasonably close proximity to the bearing housing.
  2. The heat in the bearing would surely have a negative effect on it - so it would no longer run smooth? Maybe, maybe not. That's where an expert is needed.

Can you remove the speed control components from the plinth into an external box (like many TTs have! ;) ) so bearing heat can be discounted? Many TT's now maybe but back in '77 it wasn't as common I guess. 

 

Regards,

 

Andy

 

 

If you can't find a "bearing expert" then I suggest if you take up my suggestion to externalise the motor controller, you will then at least be able to decide whether there's a problem with the bearing ... or the speed control circuitry. ;)

 

Yes, externalising the motor controller will make your Luxman non-standard - and so, potentially, reduce its "desirability" and therefore resale value - but I suggest it has little resale value in its current state! :lol:   However, I suggest you won't get much change out of 6 or 700 dollars, to put the circuitry into a nice case, with all the work involved.  And all that will do is confirm whether the bearing is the problem ... or the speed control circuit.  You'll then have further money to spend on one or the other, to fix the problem.

 

 

Regards,

 

Andy

Edited by andyr

Share this post


Link to post
Share on other sites
Guest JohnA

A turntable bearing heating up enough to affect speed control electronics? You are living in la la land.

ron

instead of mocking someone, how about offering some advice

Share this post


Link to post
Share on other sites

A turntable bearing heating up enough to affect speed control electronics? You are living in la la land.

ron

Thanks for your input Ron.

 

Cheers

 

M

Share this post


Link to post
Share on other sites

Sorry more questions. Is the bearing a sealed unit?

It really sounds like a bad resistor though.

Sorry don't know any bearing experts

Share this post


Link to post
Share on other sites

I know lots of bearing experts.

Checking and monitoring the temperature is the first port of call.

(unless it's noisy..........then you know you have a problem)

Share this post


Link to post
Share on other sites

I know lots of bearing experts.

Checking and monitoring the temperature is the first port of call.

(unless it's noisy..........then you know you have a problem)

Thanks LP,

 

The bearing seems to run very freely and is silent from what I can tell although I haven't had a stethoscope to it. I assume I'd have to get one of those thermometers to check the temp... Is there someone you could put me onto regarding this?

 

Cheers

 

M

Share this post


Link to post
Share on other sites

What sort of bearing are they using on it?

A pic or number would be good.

I'm guessing all the 'experts' I know have never worked on a turntable bearing!

Share this post


Link to post
Share on other sites

Thanks LP,

 

The bearing seems to run very freely and is silent from what I can tell although I haven't had a stethoscope to it. I assume I'd have to get one of those thermometers to check the temp... Is there someone you could put me onto regarding this?

 

Cheers

 

M

sorry to hear you have some problem with this Luxman again .

some advise for you M.

don't get anything's you just thrown your money away. just get it fix proberly by a turntable expert instead of a bearing expert . your problem have nothing's to do with your bearing as other have spoted it.

 

Duc

Share this post


Link to post
Share on other sites

Sorry to hear this problem unclemack, Im in Manly ATM and here is my $0.01 cent worth of input even though it might not apply to your issue or resolve TT bearing issues.

 

In my world( High speed Printing & not in TT world), bearings over heat for the following reasons:

 

there is no lubricant or the lubricant has dried out, this normally binds and cease the bearing, therefore it either requires lubrication or the bearing needs to be replaced

 

They are subjected to abnormal loads and often the bearing will cease to operate or lock up due to other mechanical devices failing!

 

Never has a bearing problem increases the speed of the device!

 

If a device suddenly increase speed, its normally an electronic  driver issue or a control issue, therefore I still believe there is something wrong with the speed logic control.  To test this,  is there a way to run the motor without speed control?  if this is possible then it will prove whether the logic and driver is still at fault.

2ndly I dont like pots period, cleaning them will have no effect on the wearing issues you have with typical mechanical pots, Some pots are loaded with conductive grease, so cleaning it will remove that grease and push it outside operation specs.

I have experimented with enough pots and all different type pots to come to this conclusion.  In order to get to the bottom I suggest you replace the pots regardless of what advise you have had, this way every possibility is covered. 

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Sign in to follow this  

  • Recently Browsing   0 members

    No registered users viewing this page.

×
×
  • Create New...