Turntable running fast, fluctuates

I've had a couple instances in the last month of my Clearaudio Concept Wood running noticeably fast. I'd adjust it and then check the next day and it would test different again. Could a worn belt cause that? I would've thought that would make it run slow, not fast. Problem with the motor?

I also suspect power issues, as in we're getting more than 120v. Would a power conditioner/voltage regulator help? Any suggestions?

Thanks!

 

http://www.phoenix-engr.com/#!/ - flawless product iMHO

 

Thanks, I'll check that out. Do these work with a turntable with a DC motor?

 

It appears it will not.

 

Not sure really, they have good customer svc, send them a note.

 

I talked to my local dealer that sold me the 'table. He speculated that the it may be due to he power in our area being over 120v in places (and less in others) due to the power company skimping on repeaters. He said in the last few years clients are coming in with tubes blown after only a year. Apparently another client of his is an attorney who is bringing a class action against the power company over this. I have noticed we go through a lot of light bulbs...

Anyway, while this might be true, does that explain a turntable's speed varying like that? Wouldn't Clearaudio have made it a bit less susceptible to those kinds of power fluctuations? And why am I only experiencing it in the last month, after over a year without an issue?

Could this just be a problem with the motor itself?

 

I would speak to Clearaudio first. My reaction (and only a guess) is that the motor may be fine. This turntable uses a wall wart, right? I assume you don't have a multimeter to check the voltage (not sure if current would change speed- and that's harder to measure). My impression is most quality equipment is built to run within a range of voltage for the particular country/territory. So, my "guess" might be aimed at that wall wart, if that's what your table uses.
I had a speed variance issue with my big, heavy Kuzma. Turned out it had nothing to do with belts, motors or controllers, but simply undue friction between various parts of the platter system, which was rectified by replacing one part. (Wholly different motor system and set up than yours, just pointing out that there could be a mechanical issue too that is at least worth checking). Does your dealer have any technical service capability and is he in your locale?

 

Thanks. The dealer is local (and there's at least one other local dealer for Clearaudio). I'm not sure how much work on the Clearaudio gear they do in-house, though it looks like they do work on a lot of vintage gear there.

I've emailed the US disributor Musical Surroundings about it as well, and I'll follow up with a call to them. They've been good about answering questions in the past.

I just feel like this has to be beyond a power issue for it to be just arising. The specs read this 'table has a decoupled DC motor. And it does use a wall wart, in answer to your question. You think that may be faulty?

 

I don't know, but it is certainly a potential culprit, and easy enough to replace (using one for the correct voltage and current, with correctly wired plug- easiest to get the manufacturer to supply rather than trying to find a compatable one). ClearAudio probably knows enough, based on user issues, to quickly pin-point the most probable causes, so that's where I'd start.

 

Thanks, I'll try to contact them directly as well.

 

+1 for Phoenix ( if you have a AC Motor )

 

Thanks, but it's a DC motor. I just can't understand it being only a recent development of it's something to do with the mains.

 

It's likely in the control circuit for the DC motor. Many have a potentiometer for this and either that or the surrounding circuitry can be at fault. In the most basic designs, the DC output is tightly pinned to the AC input, which is bothersome.
-Bill

 

Is the pulley tight on the motor shaft?

 

Looks like it. I emailed Musical Surroundings, and they thought the belt is the most likely culprit. He advised that if the belt has become less elastic then the tension on the motor pulley will be reduced. Less tension means it will run faster.

 

I would not doubt it. At my current residence (which I will be vacating very-soon), you should see the way the lights dim when the fridge kicks on and how the lights seem to be brighter at certain times of day. I ended up buying a pro-quality sine wave UPS (uninterrupted power supply) because of it. After having a n.o.s. Westinghouse 7591 tube redplate on me, that was it. I had to do something. Now its MUCH better. I now run all my stereo and computer gear through that thing. If I wasn't moving so soon, I would have bought another one for my fridge (I STILL may get another one regardless).

That said, I seem to notice a lot of those expensive modern tables having voltage issues, and then the company rep or salesman is telling you that you need the upgraded standalone factory power supply for only $700 more (I HAVE heard good things about the one for the Scoutmasters though). And honestly, my Dual 1019 has held a consistent speed since I got the thing like 8 years ago. Takes a couple minutes for the motor to completely-warm up, and then it's smooth sailing from there.

 

Bad cap

 

Hopefully not. I've ordered a new belt, so I'll see if that resolves it before I take it back to the dealer. It's still under warranty at least. Not sure if they need to send it away for repairs or what.

 

yes, can be a leaking Cap . if the pcboard has this kind of capacitor and the unit is on warranty my recommendation is to send this TT to repair.

 

Thanks. I'm not sure if it has a cap like that...I can't see the board. I've got a new belt coming in a couple days, so I'll try that first. If it's still a problem, in to the dealer it goes. I'm only about 15-16 months into the two year warranty.

 

Belt issues, grungy pulley and inner platter can cause wavery pitch or speed issues. And also, so can PSU issues or voltage issues especially on DC motor turntables, a big reason why I like my belt drives with AC motors on them locked to the grid. YMMV.

 

So...I cleaned the pulley and inner platter and installed a new belt. I had to readjust the speed immediately thereafter, as the new belt made it run slower than the original (which leads me to believe there was definitely a belt issue, even though it was only about 15-16 months old). I'm also trying out a Furman Elite -15 PF i. Though it's not really a voltage regulator, it may help stabilize the amp's draw at least. I will say that it seemed to improve the sound of the amp, producing a more stable image and bigger sound-stage (placebo effect? Maybe...)

I'll have to see how the turntable holds its speed over the next few days. If it's still fluctuating after this I'm going to have to pack it up and bring it into the local dealer.

 

OP, how did you test the speed being fast? I hope you did not use any of those ridiculous iphone apps.
The best tool that I have found is the KAB speedstrobe disc with the quartz lock illuminator. It is very accurate down to 99.99 %.
I have a Clearaudio Ovation and it is extremely accurate as far as the speed goes, like all Clearaudio. Clearaudio are famous for their speed stability. So, unless something in the system is broken, I would guess that the belt might be the problem. I had some issues with my belt that resulted in speed instability a few years ago but everything got back to normal after I replaced it.

 

Hey, thanks for the response! I used the AP test record and the Feickert app on the iPhone. Is that giving me an inaccurate result?

The pitch was definitely way off before I changed the belt though...it was noticeably fast. I had to dial it way down to get it back to normal with the trim screws on the back. When I put on the new belt I had to dial them back up, as it was then running too slow. So I'm hoping the belt was the culprit. I'll play with it a few days and see what happens, but I was definitely getting a lot of noticeable pitch variation (mostly running too fast) that I could tell by ear, even without a test.

 

I have the AP record and the app and yes, in my case, it was totally inaccurate cause the record was very eccentric. I sent it back to Acoustic Sounds and they sent me a replacement which was also off center. So, make sure that the test disc is not off center. Look carefully at the tonearm and see if there is any waving back and forth. If so, the results will be totally off. That's why the best is to use a strobe disc.