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audiopoor
11-19-2011, 01:35 PM
I bought this LP12 (serial no 066634) used about ten years ago and I've always wondered if this was the norm for this tt to give a bit of a grunt sound when you turn it on. I believe it's from the motor and it lasts just a second or two upon startup. I have always given the platter a helping hand, just a finger push from about 8 to 11 o clock to get it up to speed. This lessens the grunt sound by half. The valhalla power supply board was replaced by my local Linn dealer when the stock one quit working six years ago but the grunt continued. I pointed this out to him and he basically said not to worry about it. I've continued to be content with this issue and been mostly happy with the tt performance but now it's bugging me. I was at a fine audio store in Toronto last month and there sat an older LP12 with a raised red push start button, mine is the black rocker type. I turned it on and there it was again. So... is this really normal. Does anyone else hear the same?
Harv

metaphacts
11-19-2011, 02:10 PM
I bought this LP12 (serial no 066634) used about ten years ago and I've always wondered if this was the norm for this tt to give a bit of a grunt sound when you turn it on. I believe it's from the motor and it lasts just a second or two upon startup. I have always given the platter a helping hand, just a finger push from about 8 to 11 o clock to get it up to speed. This lessens the grunt sound by half. The valhalla power supply board was replaced by my local Linn dealer when the stock one quit working six years ago but the grunt continued. I pointed this out to him and he basically said not to worry about it. I've continued to be content with this issue and been mostly happy with the tt performance but now it's bugging me. I was at a fine audio store in Toronto last month and there sat an older LP12 with a raised red push start button, mine is the black rocker type. I turned it on and there it was again. So... is this really normal. Does anyone else hear the same?
Harv

Harv,

Does the table need help to get up to speed? Does the grunt come from the pulley area or from the bottom of the motor?

Take off the mat and flip over the platter. Put the inverted platter back on the table. Watch the belt and see what it does on start up. What do you see?

Bill

audiopoor
11-19-2011, 03:03 PM
The platter does get up to speed and is stable. Nice idea to invert the platter

metaphacts
11-19-2011, 03:05 PM
The platter does get up to speed and is stable. Nice idea to invert the platter

Yes but what does the belt do when you hit the on switch?

audiopoor
11-19-2011, 03:20 PM
I wasn't finished and I some how posted my last reply:confused-22: To continue, at start up the flat belt drops a bit on the pully but quickly rises back up to the middle of the pully. I got out my mechanic's stethoscope and touched the bottom of the motor at start up and there it was. I never tried this before but I tried to slow down the platter with my hand and there was the grunt, it's a motor strain noise. Anyone else getting this out of their Linn?

metaphacts
11-19-2011, 03:26 PM
I wasn't finished and I some how posted my last reply:confused-22: To continue, at start up the flat belt drops a bit on the pully but quickly rises back up to the middle of the pully. I got out my mechanic's stethoscope and touched the bottom of the motor at start up and there it was. I never tried this before but I tried to slow down the platter with my hand and there was the grunt, it's a motor strain noise. Anyone else getting this out of their Linn?


What does the bottom of the motor bearing look like? Does it have a cap on it?

audiopoor
11-19-2011, 03:30 PM
It's a round solid steel shaft about 3/4" long.

metaphacts
11-19-2011, 03:42 PM
It's a round solid steel shaft about 3/4" long.

Steel? Sure it is not the color of steel and hollow?

If your table is the vintage I think it is, it should be a cup pressed over the bottom of the motor bearing.

audiopoor
11-19-2011, 03:57 PM
You are so right. It is the colour of steel and when I gave it a quick push, to my surprise, it popped off. Inside there is a spring with a half sphere covered in white grease.

metaphacts
11-19-2011, 04:08 PM
It's a round solid steel shaft about 3/4" long.

http://img94.imageshack.us/img94/586/p10103861.jpg

Look like this?

audiopoor
11-19-2011, 04:12 PM
Now with the cap and spring off, I turned it on and just as fast I turned it off in fear of damaging the motor because of the grinding sound it's now making. What is happening now????

audiopoor
11-19-2011, 04:15 PM
Yes that is what the motor looks like but without the red painted seal around the cap.

audiopoor
11-19-2011, 04:26 PM
http://img94.imageshack.us/img94/586/p10103861.jpg

Look like this?

Do you have this tt in a jig?

metaphacts
11-19-2011, 04:26 PM
Now with the cap and spring off, I turned it on and just as fast I turned it off in fear of damaging the motor because of the grinding sound it's now making. What is happening now????


Ok should be a bushing and spring in the cap. Is there?

If so make sure the spring is straight up vertical. If not grasp it by the top and turn it in the cap until it sits straight. Take notw of the direction of the turns in the spring.

Now refit the cap on the motor and with the table sitting normally, turn on the motor. If if makes noise grasp the cup and turn it in the direction of the spring turns. Try adjusting the cup until the noise is minimized/eliminated.

Returning to one other thing, the belt should drop all the way down to the bottom of the pully when the motor first starts. If not, the motor may not be aligned properly.

audiopoor
11-19-2011, 04:53 PM
I'm still working it. It one point that seemed to elimate the grunt but now all I've been able to do is soften the sound.

audiopoor
11-19-2011, 05:50 PM
There has been a slight softening of the sound. But of course I want more. (well... less exactly) What exactly am I doing internally, when I 'm turning the cap? Just to be clear on what I'm doing...I'm turning the cap just a fraction at a time then turning it on, hear the grunt, turn it off, turn the cap a fraction, turn it on, listen for an improvement, if not repeat. Correct?
Yes the belt does drop all the way down when it starts up and it also slightly makes contact (rubs) in the fork shaped guide for just a second, then rises up and settles in half way up the pully. Alls good after that. No wavering in pitch, just steady as a rock. :)

metaphacts
11-19-2011, 06:05 PM
There has been a slight softening of the sound. But of course I want more. (well... less exactly) What exactly am I doing internally, when I 'm turning the cap? Just to be clear on what I'm doing...I'm turning the cap just a fraction at a time then turning it on, hear the grunt, turn it off, turn the cap a fraction, turn it on, listen for an improvement, if not repeat. Correct?
Yes the belt does drop all the way down when it starts up and it also slightly makes contact (rubs) in the fork shaped guide for just a second, then rises up and settles in half way up the pully. Alls good after that. No wavering in pitch, just steady as a rock. :)

Turning the cap is trying to relieve torque/tension on the spring so that the bushing centers properly putting even pressure on the bottom of the motor bearing. After you've done a few you can almost do it by feel as much sound. You may have to go back and forth a bit.

Sounds like your start up belt movement is correct.

audiopoor
11-19-2011, 07:12 PM
Thanks so much. I'll keep trying to fine tune it.
Harv

metaphacts
11-19-2011, 07:39 PM
Thanks so much. I'll keep trying to fine tune it.
Harv

I was hoping a more recent Linn guy would chime in at some point. Sold and set up many, many, many Linns in my high end retail days - which ended 25 years ago. I'm sure there are AAers far more versed than I in current Linn lore. :yes:

ronenash
11-19-2011, 11:42 PM
I think that sound is normal and is due to the high torque on the motor when its turned on. A good freind of mine has an LP12 and it behaves the same. Despite its age the LP12 is still a great table.

metaphacts
11-19-2011, 11:49 PM
I think that sound is normal and is due to the high torque on the motor when its turned on. A good freind of mine has an LP12 and it behaves the same. Despite its age the LP12 is still a great table.

When did it become normal? Never was for any Valhalla I sold/set up.

Rafale
11-20-2011, 07:48 AM
Hi
Bill I suppose that you sold and settled of the new LP12 or the verified second-and...
I would begin by cleaning the motor pulley to remove deposits of rubber, the belt should be cleaned too and checked, eventually reverse the belt or buy a new one, there is a direction, the belt has a rough side and a smooth side, finally it would be necessary to check the speed with a strob

enjoy....

jdandy
11-20-2011, 11:48 AM
I have never owned a Linn LP12, but found this thread very interesting. Bill has shared some helpful tips to those with this turntable.

metaphacts
11-20-2011, 12:19 PM
Hi
Bill I suppose that you sold and settled of the new LP12 or the verified second-and...
I would begin by cleaning the motor pulley to remove deposits of rubber, the belt should be cleaned too and checked, eventually reverse the belt or buy a new one, there is a direction, the belt has a rough side and a smooth side, finally it would be necessary to check the speed with a strob

enjoy....


Good advice Philippe, though Harv did say speed was spot on.

Well aware about the belt. Goldmund used to use them on the Reference and rejected 9 of 10 because they were not precise enough. But it was far and away the best belt at the time so there wasn't another choice.

I did say my Linn experience goes way back. At the second store where I worked, the owner had number 74. My 30 year old son once made the mistake of trying to pull himself up on my system shelf while learning to walk. The Syrinx PU2 and Koetsu Rosewood survived - and my son never went near the table again. Twenty some years later he was in Glasgow eye to eye with Ivor being told "I know who you are."

Long way to go to say I set up lots of Valhalla Linns and don't recall not being able to eliminate the noise Harv describes. If the cup adjustment doesn't do it, and your belt Rx doesn't, then he likely has an out of spec motor, ime.

Still hoping there will be a more recent Linn set up man along to make sure my old brain is remembering correctly. If nothing else they could call me out on the pic I posted. Was the first one I found that showed the motor cap but it was in a forum discussing "how not to set up a Linn"! :redface-3:

metaphacts
11-20-2011, 12:24 PM
I have never owned a Linn LP12, but found this thread very interesting. Bill has share some helpful tips to those with this turntable.

Thanks Dan. The funny thing about a Linn is that it is not finicky and it doesn't go out of adjustment all the time. Set it up right in the first place and you rarely have to mess with it, ime.

Rafale
11-20-2011, 12:49 PM
Hi Bill
I am going to ask to Ivor or to Gilad to think of your birthday present ....... a LP12 SE would be of the most beautiful effect next to your SME:D

now regarding a valhalla deck, from the good book -ie LINN dealer manual- the noise should never be loud enough to be intrusive, a good guide is that you should not hear it when you change a record. If the motor with large cap does make a noticeable, loud ticking or scraping noise, the motor bearing requires adjustment:
-check if thrust bearing consists of large ball bearing, ie 9 mm instead of 7 mm. If not replace
-ensure ball bearing and tip of spindle are well greased
-if large end cap is filled, check end of motor spindle for any rough spots, buff end of spindle with emery cloth to remove any rough spots
-re grease and re fit thrust bearing assembly to en of motor

new AC motors are inexpensive and quieter by a large margin

in 1989 at around 79 700 sn a modification designed to reduce motor noise and improue sound quality was designed and fitted as standard to all Vahalla tt. In 1991 a new small thrust cap was introduced, replacing the previous bearing arrangement, as this is glued in place it requires no maintenance but cannot be retrofitted to existing motors

metaphacts
11-20-2011, 01:11 PM
Hi Bill
I am going to ask to Ivor or to Gilad to think of your birthday present ....... a LP12 SE would be of the most beautiful effect next to your SME:D

now regarding a valhalla deck, from the good book -ie LINN dealer manual- the noise should never be loud enough to be intrusive, a good guide is that you should not hear it when you change a record. If the motor with large cap does make a noticeable, loud ticking or scraping noise, the motor bearing requires adjustment:
-check if thrust bearing consists of large ball bearing, ie 9 mm instead of 7 mm. If not replace
-ensure ball bearing and tip of spindle are well greased
-if large end cap is filled, check end of motor spindle for any rough spots, buff end of spindle with emery cloth to remove any rough spots
-re grease and re fit thrust bearing assembly to en of motor

new AC motors are inexpensive and quieter by a large margin

in 1989 at around 79 700 sn a modification designed to reduce motor noise and improue sound quality was designed and fitted as standard to all Vahalla tt. In 1991 a new small thrust cap was introduced, replacing the previous bearing arrangement, as this is glued in place it requires no maintenance but cannot be retrofitted to existing motors

Perfect! Thank you for posting this for Harv.

Puma Cat
11-20-2011, 01:32 PM
I think it's perfectly normal and you shouldn't worry about it. FWIW, my Rega Planar 3 made the same kind of sound upon startup. Guess what? I never worried about it.

It doesn't affect in any way the way the table sound when playing music.

metaphacts
11-20-2011, 01:40 PM
I think it's perfectly normal and you shouldn't worry about it. FWIW, my Rega Planar 3 made the same kind of sound upon startup. Guess what? I never worried about it.

It doesn't affect in any way the way the table sound when playing music.

The Rega makes its noise for a completely different reason and it is normal there.

It is not normal on a Linn.

audiopoor
11-20-2011, 04:21 PM
Hi Bill
I am going to ask to Ivor or to Gilad to think of your birthday present ....... a LP12 SE would be of the most beautiful effect next to your SME:D

now regarding a valhalla deck, from the good book -ie LINN dealer manual- the noise should never be loud enough to be intrusive, a good guide is that you should not hear it when you change a record. If the motor with large cap does make a noticeable, loud ticking or scraping noise, the motor bearing requires adjustment:
-check if thrust bearing consists of large ball bearing, ie 9 mm instead of 7 mm. If not replace
-ensure ball bearing and tip of spindle are well greased
-if large end cap is filled, check end of motor spindle for any rough spots, buff end of spindle with emery cloth to remove any rough spots
-re grease and re fit thrust bearing assembly to en of motor

new AC motors are inexpensive and quieter by a large margin

in 1989 at around 79 700 sn a modification designed to reduce motor noise and improue sound quality was designed and fitted as standard to all Vahalla tt. In 1991 a new small thrust cap was introduced, replacing the previous bearing arrangement, as this is glued in place it requires no maintenance but cannot be retrofitted to existing motors


More good information, thanks guys. I just turned the table on now and I feel there really isn't a satisfying improvement. Last night I would have sworn the grunt was cut in half. It would have been warmed up more than it is right now so maybe that could make a difference. Just to be even more detailed- when I start the tt, say it's at 6:00, the rotation starts slowly and is quiet till 10:00, then the grunt starts and the platter is picking up it's most speed and reaches top speed by 4:00 and at this point the grunt stops. Quiet and stable from this point on.
My tt motor and cap do look identical to the one in the picture. Is this cap considered the large one?
If I'm checking the motor spindle as suggested, does this mean to look up into the bottom of the motor with the cap off...but what am I looking for? Should the end of the motor spindle be a flat or a rounded surface? Can this spindle be moved in or out or it just spins.
I don't mind trying anything but it may be challenging to get up close and personal to the bottom of the motor. A jig would help. Are ther any pics of this spindle anywhere?
Thanks Harv

Rafale
11-20-2011, 05:06 PM
Hi Harv, see the pic below and check your motor bearing
http://i1113.photobucket.com/albums/k517/phidelrv/linnmotor.jpg
it is a Peter Swain's pic- Cymbiosis UK -the man who talks to LP12's ears

audiopoor
11-20-2011, 08:05 PM
I will post some pics after my subscribership goes through. HEA! I'm a subscriber now. I got drawn in and I couldn't get out. Plaese, nobody help me!
Back to business, I'd say the cap on the left looks like mine but the spindle shaft end on the motor in the middle, is different. Mine is wider. This one looks too skinny. Pics to come.

metaphacts
11-20-2011, 08:27 PM
I will post some pics after my subscribership goes through. HEA! I'm a subscriber now. I got drawn in and I couldn't get out. Plaese, nobody help me!
Back to business, I'd say the cap on the left looks like mine but the spindle shaft end on the motor in the middle, is different. Mine is wider. This one looks too skinny. Pics to come.

Is it possible you have a bushing over the bottom of the shaft - a wide flat surface with a small dimple?

audiopoor
11-20-2011, 08:54 PM
YES. That is what it looks like. How did you know that? Experience matters and worth the cost to subscribe. I tried to pull down on the shaft with my fingers but with the grease and if it's a bushing, it's in there tight. Do I need to remove it?

metaphacts
11-20-2011, 09:07 PM
YES. That is what it looks like. How did you know that? Experience matters and worth the cost to subscribe. I tried to pull down on the shaft with my fingers but with the grease and if it's a bushing, it's in there tight. Do I need to remove it?

No. You need to make sure that the little bushing on top of the spring is smooth and properly greased as per Rafale's post from the Linn Dealer manual. Also make sure the spring comes out of the cap parallel to the cup's sides. You want to make sure the high point of the bushing in the spring is aligned with the dimple. That's what you are adjusting as you turn the cap on the bottom of the motor.

audiopoor
11-20-2011, 09:20 PM
I'll put it back together tonight and show you something else if I'm allowed to post attachments tomorrow.

audiopoor
11-23-2011, 08:53 PM
So I'm unable to post pics untill Paypal goes through. So I'm finding out, Paypal takes up to eight days to process your transaction and forward your money. I guess they are earning interest on it for a few days. Multiply that by ten's of thousands of transactions and they're making some mula $$
I'm not making any progress with the grunt but what I wanted to show was that the spring cannot sit perfectly straight up and down because the bottom of the spring does not have a finishing coil. It's like it is just cut to length, so it sits lopsided. It doesn't take much grease in the cap to hold the spring centered and straight but it wouldn't take much for the thrust bearing to go to one side once the cap is pushed into place. Are all springs like that?

metaphacts
11-23-2011, 09:01 PM
So I'm unable to post pics untill Paypal goes through. So I'm finding out, Paypal takes up to eight days to process your transaction and forward your money. I guess they are earning interest on it for a few days. Multiply that by ten's of thousands of transactions and they're making some mula $$
I'm not making any progress with the grunt but what I wanted to show was that the spring cannot sit perfectly straight up and down because the bottom of the spring does not have a finishing coil. It is like it is just cut to length, so it sit lopsided. It doesn't take much grease in the cap to hold the spring centered and straight but it wouldn't take much for the thrust bearing to go to one side once the cap is pushed into place. Are all springs like that?

No! If the spring in not finished top and bottom there may be a problem with it. Cheap fix to replace it.

audiopoor
11-23-2011, 09:41 PM
Yeah, it just doesn't seem right to me. Maybe, I should take the spring and cap to my local Linn dealer in Whitby and see what he says. He's not showing Linn products like he used to. He might have one room with a few pieces. Mostly home theater now, just to stay alive.

metaphacts
11-23-2011, 10:14 PM
Yeah, it just doesn't seem right to me. Maybe, I should take the spring and cap to my local Linn dealer in Whitby and see what he says. He's not showing Linn products like he used to. He might have one room with a few pieces. Mostly home theater now, just to stay alive.

Just make sure he still owns a table himself. Lots of very good Linn dealers out there who got on board more recently who have no idea about tables.

audiopoor
11-29-2011, 08:08 PM
So I'm unable to post pics untill Paypal goes through. So I'm finding out, Paypal takes up to eight days to process your transaction and forward your money. I guess they are earning interest on it for a few days. Multiply that by ten's of thousands of transactions and they're making some mula $$
I'm not making any progress with the grunt but what I wanted to show was that the spring cannot sit perfectly straight up and down because the bottom of the spring does not have a finishing coil. It's like it is just cut to length, so it sits lopsided. It doesn't take much grease in the cap to hold the spring centered and straight but it wouldn't take much for the thrust bearing to go to one side once the cap is pushed into place. Are all springs like that?

Just to update, I called my local Linn dealer on the weekend and was suprised to find out they are no longer a distributer but can still get parts. He says there were different solutions over the years for the motor thrust bearing (as seen in pics above) and doubts that just a spring would be available. So I'm waiting for a reply.http://www.audioaficionado.org/members/audiopoor-albums-lp12-motor-thrust-bearing.html

audiopoor
11-29-2011, 08:23 PM
Sorry, I was trying to show three pics. I don't get how to do it now.

chessman
11-29-2011, 09:56 PM
Click on the landscape icon, then cut and paste the url in the dialog box

Masterlu
11-30-2011, 07:57 PM
Here they are, I'm on my cell phone.

http://www.audioaficionado.org/members/audiopoor-albums-lp12-motor-thrust-bearing-picture717-spring-seems-cut-length-without-finishing-coil.jpg

http://www.audioaficionado.org/members/audiopoor-albums-lp12-motor-thrust-bearing-picture715-bottom-motor-grease-cap-romoved-exposing-bushing-centering-dimple.jpg

http://www.audioaficionado.org/members/audiopoor-albums-lp12-motor-thrust-bearing-picture716-grease-cap-thrust-bearing-spring.jpg

audiopoor
12-01-2011, 07:58 PM
Thanks so much for posting my pics for me. I did highlight and copy the ULR given to my picture in my album section then paste the ULR in the Landscape dialog box. Not sure what I'm doing wrong.
You can see how crooked the sping stands on it's own and then in the cap it's straight with the help of grease. But, does it stay that way? The bushing is shown with the centering dimple for the thrust bearing.

chessman
12-01-2011, 08:16 PM
Do not copy the URL of the website. Instead right click on the photo and choose "copy image location." Sorry my prior advice was vague. :(