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There is a VERY slight wobble on a Technics 1200 turntable that I purchased (cheaply). I found a mark on the platter that leads me to believe that something may have been dropped onto it. The wobble is barely perceptible (but it's there).
I cannot see or feel any movement on the spindle. I have checked the screws that hold the spindle in place and all seem to be tight. My only guess is that the spindle may have been damaged. I planned on replacing the spindle (a new one is only $30, and it appears to be an easy job). Anyway, I thought I'd get some opinions before doing this.
If no skipping is taking place, is this worth replacing?
Well, I just spoke with KAB about this issue. They are very nice and very helpful, by the way. It sounds like it is very unlikely that it is a spindle problem. Instead, it's probably one of four different problems:
My imagination (there's a pattern on the side of the platter that can create an optical illusion);
The platter is not sitting properly because I (and the previous owner) did not seat it carefully enough;
There are dents in the platter hole (don't remember the technical term); regardless, these can be fixed without much expense;
The platter itself could be warped (obviously the worst scenario).
I don't have the turntable with me, so I can't confirm the problem. I'm hoping it's just my imagination, though.
--asdf
Last edited by asdf; 04-23-2008 at 08:03 PM.
Reason: formatting (numbered list)
If you hold a piece of soft chalk close, then closer, then closer, then closer to the platter as it spins, you can find the high spot if there is one, or maybe find that it is, indeed, an illusion. On the other hand, your 1200 may have the same problem mine had, and it is common to direct-drive turntables: cogging. As the whole thing turns, one part of the motor swings past the coil [or pole], and gets a boost. Before it reaches the next coil [or pole] it slows down. So, you see, it is always speeding up and slowing down - cogging. I have been told that only Hitachi Uni-Torque motors are immune to this, but then you have to settle for Hitachi. My 1200 got so bad I had to sell it for peanuts.
Worry not! There are gobs of good tables out there!
Laz
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Welcome aboard. You are now looking at the objective reality: please stay focused.
Why, oh why, didn't I take the BLUE fez?!
But you keep looking over your shoulder to see if I am there.
TEAM Mac//TEAM STAX//TEAM MUSTAPHA//TEAM HORRI-FI//TEAM TOO MANY TEAMS
There is a VERY slight wobble on a Technics 1200 turntable
There is often a bit more play in a direct drive platter if you rock it than a belt drive as the spindle is part of the motor so the tolerances are never going to be as tight as on a belt drive. This is just part of the design and shouldn't be a cause for concern unless what you are describing is that the platter has become warped somehow and rises and falls as it spins, which would indicate more serious issues.
Well, I haven't played it, yet. My new cartridge hasn't arrived, but I'm hoping it's waiting for me at home. I don't want to let the previous owners' cartridge get anywhere near one of my albums (even though it sounded fine on his system).
I'll have to try the chalk trick. I spent 15 minutes studying it (after reseating it), and I can't decide whether or not the wobble is actually there. That's probably an indication that it won't affect the sound. We shall see.
If you hold a piece of soft chalk close, then closer, then closer, then closer to the platter as it spins, you can find the high spot if there is one, or maybe find that it is, indeed, an illusion. On the other hand, your 1200 may have the same problem mine had, and it is common to direct-drive turntables: cogging. As the whole thing turns, one part of the motor swings past the coil [or pole], and gets a boost. Before it reaches the next coil [or pole] it slows down. So, you see, it is always speeding up and slowing down - cogging. I have been told that only Hitachi Uni-Torque motors are immune to this, but then you have to settle for Hitachi. My 1200 got so bad I had to sell it for peanuts.
Worry not! There are gobs of good tables out there!
Laz
Cogging is theoretically an issue with all electric motors and since all the turntables I know of use them, no drive system can totally escape the problem. A turntable can be no better than its motor regardless how well the rest of it is made. Since the platters and motors on direct drive tables are essentially one, cogging should be a bit more of an issue but this is more theory than real listening experience. If an audible cogging symptom is experienced on a Technics or an other high quality turntable, I would blame a faulty motor instead of the drive system.
Cogging is theoretically an issue with all electric motors and since all the turntables I know of use them, no drive system can totally escape the problem. A turntable can be no better than its motor regardless how well the rest of it is made. Since the platters and motors on direct drive tables are essentially one, cogging should be a bit more of an issue but this is more theory than real listening experience. If an audible cogging symptom is experienced on a Technics or an other high quality turntable, I would blame a faulty motor instead of the drive system.
If this were the case, would replacing the spindle assembly fix the problem?
If this were the case, would replacing the spindle assembly fix the problem?
no.
if you ave audible cogging you will know INSTANTLY. it is a VIOLENT speed instability.
the technics uses a DC motor, which does not eliminate cogging, but certainly limits it compared to an AC one.
if the dot for the speed ring kind of fades in and out at a fixed pace i would nto wory too much. see if you can get the +3 or -3 dots to be still. the center "dent" bypasses the slider, and does not always EXACTLY meet 33.333RPM. it could be 33.34.
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Originally Posted by mkmelt
ACHTUNG - ALLES KOPFPHONERLISTENERS
Alles kopfphonerlisteners non-technischens! Das tubenmachine is nicht for gefengerpoken und mittengrabben. Oderwise is easy schnappen der springenverk, blowenfus, und poppencap, mit spitzensparken, und smokentubes. Geverken inside der tubenmachine is fur der experten only. Is nicht fur geverken inside by das dumpkopfen. Das rubbernecken amateuren keepen das cotton-picken hands in das pockets. Just relaxen, enjoyen der musik, und vatchen das pretty glowentubes.
no.
if the dot for the speed ring kind of fades in and out at a fixed pace i would nto wory too much. see if you can get the +3 or -3 dots to be still. the center "dent" bypasses the slider, and does not always EXACTLY meet 33.333RPM. it could be 33.34.
The dot for the speed ring does fade in and out (but it's barely perceptible). Are the +3 and -3 dots the ones immediately above and below the main dot? Does it matter if they are closer to +4 -4 dots?
Wobble on platter (Technics 1200)
Linear Mode
