SL-D2 acceptable speed variation

w1zz4

New Member
Hello,

Is there any norm about acceptable speed variation? When I look at the dots, it's moving back and forth in the same dot for about 1 1/2 minute while gradually moving to the next dot and then moving back and forth in this dot, gradually moving to the next one and goes on and on...

I don't ear specific pitch problems but it stress out my OCD a bit.

Is it normal speed variation?
 
The D2 doesn't have any mechanism that controls the speed for you. Its up to the user to eye ball the correct speed then cue. I am always making small adjustments to mine between LPs. I just chalk it up to a fact of life with this table. I also feel as if hitting 33 1/3 rpm manually, yourself is probably next to impossible so I don't worry about it too much. When it looks close enough to right I go.

Sent from my Nexus 7 using Tapatalk
 
I would not worry about it too much, but my D2 stays on the dot when I adjust it. Could be your power in your house.
 
I've had the D2 and D3 and they both drifted a small amount while running. Seem to be just the way they are, could be due to age also. I currently run a belt drive no strobe to scrutinize while playing records.
 
Hello,

Is there any norm about acceptable speed variation? When I look at the dots, it's moving back and forth in the same dot for about 1 1/2 minute while gradually moving to the next dot and then moving back and forth in this dot, gradually moving to the next one and goes on and on...

I don't ear specific pitch problems but it stress out my OCD a bit.

Is it normal speed variation?

Try cleaning the pitch adjustment switch and all speed switchs/pots with DeOxit. :music:
 
I would not mess with it by trying to clean the pots unless you really know what you are doing. You can't hear that slight amount of variation so just enjoy listening to your records. Sometimes there is very slight variation with belt drive turntables.
 
I would not mess with it by trying to clean the pots unless you really know what you are doing. You can't hear that slight amount of variation so just enjoy listening to your records. Sometimes there is very slight variation with belt drive turntables.

The SL-D2 is direct-drive.
 
I don't know what I'm doing ever. My fists are made of ham and to me tools are things for adults to use.

That being said identifying the proper pot and furthermore, cleaning all of them with deoxit took all of five minutes. Take the bottom off. Carefully remove the board with the pots on it. Apply
Put back together. Work pots. Let dry.

Sent from my Nexus 5 using Tapatalk
 
The D2 is a pretty precision table for one so inexpensive. Get the pots clean, carefully set the speed and it should be good, at least for the session. So it is with mine, anyway. Cleaning the pots made all the difference with mine, that I can tell you. YMMV
 
It could be just the platter mirror-dots. Recommend confirming this with a speedstrobe disc and comparing the results with one or two other known good turntables.

With such a mass-produced table from such a recognized expert in the process I highly doubt the dots are off. As the others said, clean the pots, & lube the spindle. Then sit back and enjoy!
 
Hello,

Is there any norm about acceptable speed variation? When I look at the dots, it's moving back and forth in the same dot for about 1 1/2 minute while gradually moving to the next dot and then moving back and forth in this dot, gradually moving to the next one and goes on and on...

I don't ear specific pitch problems but it stress out my OCD a bit.

Is it normal speed variation?

Yes, there is a norm for acceptable speed variation. The DIN standard calls for a speed accuracy of +/- 0.2% for professional equipment, 2% for consumer equipment. According to your post, your SL-D2 is much more accurate than that - in fact, better than the mains so you can't really tell whether you are seeing the fluctuations of your turntable or of the mains - seriously! You are overthinking this :D And you are unaware of several points that will make you sleep better (or worse, depending on your temper ;) ) once you know them:

- The SL-D2 is not crystal-driven, it uses a resistor-capacitor circuit to set its speed, and both components have some temperature drift. As a result, it is perfectly normal for the speed to evolve over the first 15-30 minutes, and to fluctuate somewhat even after that.

- The stroboscope of the SL-D2 is not crystal-driven either. It is synchronised to the mains which is not perfectly stable: the regulations allow 0.1% drift on a regular basis, and even worst-case fluctuations of 1% for a limited time. It is not considered important as long as the long-term average frequency is accurate. So don't take that stroboscope too litteraly, it is not completely accurate either.

- At 33 1/3 RPM the stroboscope dots are accurate, but at 45 RPM they are off. This is because it is impossible to match the mains frequency with an integer number of dots. The difference is not taken into account when engraving the 45's, so if you adjust the speed with the stroboscope you are very slightly off - and don't even notice ;)

- You will never get the stroboscope perfectly still, so stop staring at it and enjoy the music instead ;)

- If you really really must know the speed accuracy of your turntable (and assume that your mains is perfectly accurate), you can measure it by the time it takes for a dot of the stroboscope to visually drift to the position where its neighbour was. The speed drift is given by the following formula:

dS = 1 / (F * t)

where:

  • dS = relative speed drift (multiply this figure by 100 to have it in %)
  • F = strobe frequency: for the SL-D2 it is 100 or 120 Hz depending on your country.
  • t = virtual strobsocope drift, in seconds/dot.

Oh yeah, one last thing: since the speed tends to drift a little for the first minutes of playing, it is best to adjust it only after roughly half an hour of spinning. After that it will remain practically constant.
 
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It happens; the bars, too.

Bring speedstrobe disc to a Sam Ash store and hang out. :smoke:

Granted. I'm not saying it ca't be off by a hair. But as jib2 has stated so well, I don't think the op has anything to worry about. And as I said, sit back and enjoy the music. :)
 
Digital Turntable Tachometer

- If you really really must know the speed accuracy of your turntable (and assume that your mains is perfectly accurate), you can measure it by the time it takes for a dot of the stroboscope to visually drift to the position where its neighbour was. The speed drift is given by the following formula:

dS = 1 / (F * t)

where:

  • dS = relative speed drift (multiply this figure by 100 to have it in %)
  • F = strobe frequency: for the SL-D2 it is 100 or 120 Hz depending on your country.
  • t = virtual strobsocope drift, in seconds/dot.

It's hard to believe that no one came up with a better system to measure platter speed than this; until now:

RoadRunner digital tachometer. 3 decimal places of resolution. First reading within 2 revs, updates every rev afterwards. 2.5ppm time base (±0.00025%).
 

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It happens; the bars, too.

Bring speedstrobe disc to a Sam Ash store and hang out. :smoke:

It's important to remember that the OP said the dots appear to oscillate (move back and forth) as they advance. There's no way that poorly calibrated dots on the platter rim could oscillate.

John
 
i have to adjust the pitch control on my D2 every time i put a record on. im OCD about it too. i haven't cleaned the pots yet so the slightest turn makes the pitch way off, kind of annoying.
 
...When I look at the dots, it's moving back and forth in the same dot for about 1 1/2 minute while gradually moving to the next dot and then moving back and forth in this dot, gradually moving to the next one and goes on and on...

I'm gonna regret jumping in here, I know I am...

The OP's statement suggests two separate issues to me, wavering and speed accuracy. The moving of the strobe marks from one dot to the next, even while wavering, is a speed issue and should be correctable by the pitch control (they can be very sensitive).

The wavering may be a number of things. Can I suggest that you put a small paper arrow or reference mark between the platter mat and the platter to try and see if the wavering is once per revolution. That would suggest a mechanical problem.
 
It's important to remember that the OP said the dots appear to oscillate (move back and forth) as they advance. There's no way that poorly calibrated dots on the platter rim could oscillate.

I'm gonna regret jumping in here, I know I am...
Why would you? The worse thing that can happen is to learn new things :)

As regards the wavering, it is almost always caused by the platter being slightly off-centre. Don't sweat it, they all are, more or less. It the amplitude is small, it's not a problem. If the dots move a full position back and forth (or more), if the frequency of the wavering is not once per revolution (great test idea BTW 12ax7), or is irregular, then they may be a more serious issue.
 
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