Using my deck late one night when all was very quiet I noticed my LP12 making a low level whinning-groaning noise, after the start up groan. The sound varies in pitch and is regular in it's cycle. If you look at a spot on a record label the pitch cycles with about one revolution. You really need to get your ear close to the plinth to hear it but if it's very quiet you will hear it even standing near it.
I immediately took a flash light and peaked under the platter at the belt to make sure it wasn't ridding low and rubbing the belt guide. I even took the platter off flipped it over and double checked. I myself recapped the valhalla less than a year ago. I emptied and carefully cleaned and refilled the bearing w/ Linn oil at he time too. It looked fine and shiny.
What's causing this? Motor or Valhalla, other? It's an old deck I got it used but it has been nirvana'd and valhalla'd. I had a good Linn dealer do a set up and it's been sounding fabulous.
Has a cap failed? Is it other board parts? Motor failing? Maybe the motor height/belt angle screws are pushing too hard on it? I wish I had a stethoscope but I don't.
If it's the Valhalla, this thing is a bit beyond me. My approach to rebuilding it would be to shotgun anything I can replace - the wirewounds and the caps again. I don't have a scope and I wouldn't know how to approach this thing anyway. Anyone know what parts I should just pull and replace?
Maybe it's time to build that 'geddon w/ the Plitron trany I've been planning on but I really don't feel like buy a new motor right now too.
Any advice will be appreciated.
Posted on: 15 April 2002 by Mark Dunn
Hi rp:
The motor may be making the whining noise but unlikely it will groan. Take the plater off, start the motor and put your ear to to it. If it's whining, gently prod it a couple of times from directly above with a finger in the well of the drive pulley. This will help reseat the bearing at the base of the motor.
Groaning is often caused by the suspension's rubber grommets (the large top ones) rubbing ever so slightly against the suspension plate. This can be cured by removing them and applying some talc as a lubricant. However it does indicate that set-up of the suspension isn't perfect.
Please take the above as ideas only as it's hard to diagnose strange noises from afar!
Best Regards,
Mark Dunn
Posted on: 15 April 2002 by rp
I don't think it's the suspension, though I really don't know and will check this too, only because the sound is steady and its pitch varies cyclically with time. I described it as a groan only because it is more of a mid-low frequency sound than whine which to me implies a high frequency whistle sort thing. It's a bit of a buzzy sound. A bit like hearing someone vacuuming the apt. next door only from 10 miles away.
Looks like I'm going to have to open the kitchen table again and crawl under the &%$# TT with a paper towel tube to my ear. Gonna have to wait till the paper towel runs out first though.
This would be a good time to shotgun the Valhalla, regardless if it's causing the trouble. If anyone knows what parts should go, besides the big caps, please let me know so I can order them ahead. I guess the big toasted-looking wirewounds should go even if they're in spec. Anyone have a schematic!?
Posted on: 15 April 2002 by Paul Ranson
If the noise is keyed to the platter it's unlikely to be the motor or Valhalla.
Which doesn't leave much... If you take the belt off and push the platter round is it silent? If you then run the motor is it silent?
Paul
