Erratic motor Audio-Technica AT-LP120-USB?

[splendidmike]

Erratic motors aren't normal, right?

Hey folks,

So I got an Audio-Technica AT-LP120-USB turntable from Amazon today and was instantly off to a bad start. The azimuth on the pre-loaded cartridge was way off and I had to unmount the tone arm from suspension to fix it.

After I finally got that under control, playing the first record, there was very audible noise coming through from the motor, almost like a knocking. When I took the platter off and started it up, the spindle was spinning very erratically, even going backwards at times.

Here's a youtube video of the problem:
http://www.youtube.com/watch?v=GfaG1BpyvM0

What's strange to me is that the motor seems to spin at correct speed with the platter on, but not with it off. Anyway, the real problem is that there's an audible "knocking" when playing records. You can even hear it just listening to the platter spin.

So, this is bad, right? Anyone encountered this before and have a fix or should I just send it back?

Thanks for your thoughts,
Mike

 

[BrocLuno]

Call Amazon and get an RMA # ASAP. Send that thing back. The motor circuits are not trivial. You got a bad one. Get a good one

 

[majick47]

BrocLuno I assume "get a good one" is suggesting the OP purchase a turntable that has a history of reliability and good build quality.

 

[Dr Tinear]

BrocLuno I assume "get a good one" is suggesting the OP purchase a turntable that has a history of reliability and good build quality.

+1 on this implied recommendation to get something other than a replacement AT-LP120-USB. If the OP has a Best Buy with a Magnolia Hi-Fi department nearby, he might be lucky enough to score a Pro-Ject Debut III on close-out for about the same price as the AT. The Debut III is not my favorite turntable, but it's better built than the A-T and should easily outplay it. Otherwise my recommendation would be to hit the used vintage market on Craigslist or at local thrift stores.

Apparently the phrase "Chinese quality" is still an oxymoron, at least where Audio-Technica turntables are concerned ...

 

[splendidmike]

OK, the turntable is on it's way back, but I'd still love for someone to enlighten me: How is it possible for the motor to spin so erratically when it's not under load and then correctly with the platter on? (knocking noise notwithstanding). This is not a common behavior for direct drive quartz tables?

For what it's worth, I probably won't get another LP120 after this experience, but there are many many satisfied reviews on the net by people who seem to know what they're talking about (and buying at this price point). Pitch control is important to me, which was one of the main reasons I went with it.

 

[radioman76]

I saw the video, and the cause is simple electromechanical physics. It's an AC motor, and one or more of the coils was bad, or simply had inverse polarity. With the platter off, that coil then jerks the motor in the opposite direction. Put the platter on, and momentum becomes a factor - overcoming the pull of the bad coil. The "knocking" may have been a result of the bad coil pulling the driveaxle out of alignment.

 

[splendidmike]

Thanks

I saw the video, and the cause is simple electromechanical physics. It's an AC motor, and one or more of the coils was bad, or simply had inverse polarity. With the platter off, that coil then jerks the motor in the opposite direction. Put the platter on, and momentum becomes a factor - overcoming the pull of the bad coil. The "knocking" may have been a result of the bad coil pulling the driveaxle out of alignment.

Thanks radioman, that seems plausible. I didn't think that could be an acceptable behavior for a turntable, but I just wanted someone's second opinion. Thanks folks. M

 

[majick47]

splendidmike a simpler explanation re your problem with the AT USB TT is that there is minimal quality control in the mfg of these new low end TTs and you would get a lot better performance from a vintage TT that was built to higher standards than what we see today.

 

[splendidmike]

there is minimal quality control in the mfg of these new low end TTs and you would get a lot better performance from a vintage TT that was built to higher standards than what we see today.

That may be true, but I also wanted to document this problem in case others run into it. I couldn't find anything on the net about this kind of behavior on a quartz direct drive turntable. Separate issue, but I also couldn't find anything on the azimuth problem I had. I wonder how many LP120 owners are unknowingly chewing up their records. The arm (not just the headshell) was probably off by 20 degrees.

 

[majick47]

splendidmike your feedback/report re the problems (motor/azimuth) you had with the LP120 should be adequate warning to potential buyers of this turntable. Not sure if this is the case with you but my guess is that a good percentage of people looking at this TT have never seen/used a TT before and are unaware of the much higher level of performance of a well designed/built turntable. Hopefully more people will check AK and read stories like this before they plunk their money down for one of these TTs.

 

[iLUVanalog]

I also have the AT-PL120 (non-USB version) and encountered the same issues. The azimuth was easy enough to fix. Another issue was the counterweight. When I initially set up the table, the counterweight was really loose-fitting in the counterweight post, but a quick tightening of the set screw on the counterweight itself, and all was well. The motor issue I had also. There was the very low level "knocking" sound, and the speed stability (even with quartz-lock) was slow. I thought it rather careless of AT to let a table get through that wasn't really "ready to ship" unless/until these issues were addressed. However, despite the above, it's a good table. Not "high end" by any means, but I didn't buy it for that. Once I tightened up a couple of things, it actually performs rather well. Of course, not quite up to the standard of my SL-1200, but not too shabby nevertheless. As for the issue with the erratic motor behavior with the platter off, I didn't worry too much about that because of the simple fact that a turntable is never used without the platter, and I figured that was caused by the magnetic nature of the drive system. The issues IMO were minor and once tended to, did not detract from or deteriorate the sound quality. Others may be much more fussy when it comes to this sort of thing, but I just don't think it is necessary to go into panic mode.

 

[splendidmike]

I also have the AT-PL120 (non-USB version) and encountered the same issues. The azimuth was easy enough to fix.

I'm new to audiokarma, and it seems like the general level of technical know-how is pretty high, but I can assure you that fixing the tone arm/azimuth problem I encountered was not something that the average consumer would know how to do, if they knew they had a problem at all. It's not even something you could attempt without the right screwdrivers, and not something I would suggest unless you've got tons of patience and some previous experience taking apart electronic components. I won't go into the whole process, but this guy kind of explains what I had to do to fix it, and I would consider my azimuth fix a hack to correct a manufacturing problem rather than an adjustment.

The issues IMO were minor and once tended to, did not detract from or deteriorate the sound quality. Others may be much more fussy when it comes to this sort of thing, but I just don't think it is necessary to go into panic mode.

And I'll disagree with you big time there. I'm not trying to start a panic either, but these problems were not minor. After I went through all the trouble of fixing the tone arm, the instant I put the needle on a record, I could clearly hear the motor knocking through my speakers. That's what made me take the platter off and examine it in the first place. It wouldn't have taken an audiophile to hear that something was wrong. In addition to the unacceptable audio quality, to me that knocking means lots of unnecessary vibrations that are potentially causing undue wear on my records and/or needle.

It's possible I just got a dud, or it's possible that the unit was damaged by some pretty horrible packaging on Amazon's part, but either way, my confidence in this model is shot. Maybe I would think differently if I could go to a physical retail store and examine an LP120 in person before buying it, but shelling out $200 for something that would have sounded worse than the $25 turntable it was replacing and could be damaging every single record I play is not a bargain.

 

[iLUVanalog]

I'm new to audiokarma, and it seems like the general level of technical know-how is pretty high, but I can assure you that fixing the tone arm/azimuth problem I encountered was not something that the average consumer would know how to do, if they knew they had a problem at all. It's not even something you could attempt without the right screwdrivers, and not something I would suggest unless you've got tons of patience and some previous experience taking apart electronic components. I won't go into the whole process, but this guy kind of explains what I had to do to fix it, and I would consider my azimuth fix a hack to correct a manufacturing problem rather than an adjustment.

And I'll disagree with you big time there. I'm not trying to start a panic either, but these problems were not minor. After I went through all the trouble of fixing the tone arm, the instant I put the needle on a record, I could clearly hear the motor knocking through my speakers. That's what made me take the platter off and examine it in the first place. It wouldn't have taken an audiophile to hear that something was wrong. In addition to the unacceptable audio quality, to me that knocking means lots of unnecessary vibrations that are potentially causing undue wear on my records and/or needle.

It's possible I just got a dud, or it's possible that the unit was damaged by some pretty horrible packaging on Amazon's part, but either way, my confidence in this model is shot. Maybe I would think differently if I could go to a physical retail store and examine an LP120 in person before buying it, but shelling out $200 for something that would have sounded worse than the $25 turntable it was replacing and could be damaging every single record I play is not a bargain.

While I could hear a very low-level "knocking/clicking" sound when I had my ear right by the spindle, I did not hear the knocking sound coming through the speakers. Further, re. azimuth, there was no mention anywhere in my post anything to the effect of "anybody can do it". And if there is, show me....you won't find it. Yes, I was able to correct the azimuth on my table, and yes, it was fairly easy for me to do. I have the patience, I have the right size screwdrivers, I have the lightweight level to make the adjustment more precise, etc. For me, it was time well-spent. Needless to say, if you are not comfortable doing that sort of thing, your best option is to immediately return the turntable for either a refund or a replacement. I will say is that I have used my AT-PL120 regularly since I bought it brand new over a year ago, and have not had the problem you are experiencing with yours. Also, if you are concerned about wear on your lp and/or your stylus, think about the following:...anytime you play an lp that is warped, you run the same risk....anytime you play an lp with excessive scratches, etc., you run the same risk.....anytime you play an lp and don't have the antiskating set properly and the stylus skids across the lp, same risk.

 

[majick47]

For $200 new out of the box most people would expect the thing to operate/function in some reasonable fashion. And what it is for $200 is a TURD/POS, lets call it what it is and hopefully the word will get out and others wont make the same mistake. For $200 the OP could of gotten an excellent performing/sounding "vintage" turntable that would run rings around the AT in performance/function/design/materials/quality.

 

[BrocLuno]

Huh ...

Man there are a lot of AT bashers here You love their cartridges, mic's and headphones, and hate their TT's :scratch2: Seems to be a bit of the anti-AK here - all attitude and no audio :thumbsdn: I detect a LOT of attitude.

I've been driving an AT PL120 (pre-USB) for about 4 years now. About a 200 headshell changes (cartridge swapper) and arm adjustments and never a whimper. Dead on speed and decent to good sounds.

If the OP has a bad one (and I think we can all agree that he does?) - he needs to make the seller take it back and send him another or refund his money. As long as it's all at their expense, what's the deal? My guess is that number two will be OK - let's see :scratch2:

I'll put my 120 up against all sorts of "vintage" decks that can have all sorts of issues. Is it the best table ever built of course not. Is it a good workhorse and 78 spinner - mine is. Maybe the OP will get a decent one also? Let's wait and see.

There's a lot of steam right now, time to cool off?

 

[splendidmike]

Man there are a lot of AT bashers here You love their cartridges, mic's and headphones, and hate their TT's

That's funny, I actually almost wrote previously, but erased: I was a media technician for four years in a university media production program, and would happily vouch for their mics (never used their headphones)!

The online Amazon return system was a snap, and UPS has already picked up the turntable free of charge. I didn't even have to print out a return label. Amazon is in the process of refunding my money. I have no real complaints other than the 6 or 7 hours the whole ordeal cost me.

I've been driving an AT PL120 (pre-USB) for about 4 years now. About a 200 headshell changes (cartridge swapper) and arm adjustments and never a whimper. Dead on speed and decent to good sounds.

I do sincerely hope that I haven't come across as trying to trash the reputation of an entire product line just because I had a bad turntable. I'm totally willing to accept that I got a lemon. Like I said before, I did a lot of online research and found that many people, who were obviously knowledgeable about turntables, were satisfied with their LP120-USB. I am opting for a refund rather than a replacement for two primary reasons:
- Amazon's packaging really was terrible. I shipped it back in better condition than it came to me. I simply don't trust their packaging department at this point. I've also gotten damaged vinyl from them before.
- If the machine wasn't damaged in transit, (and the tone arm problem at least was likely not in-transit damge) it seems likely that I would be given a replacement that was from the same manufacturing run. I don't want to risk that.

There's a lot of steam right now, time to cool off?

Agreed! Again, thanks so much for all your input everyone. Time to move on to a different thread... tomorrow morning I'm going to make an "unboxing" video of the Ortofon 2M Red I was going to put on that table! Will post a link on AK when it's done.

 

[Miguel760]

I had the pl120, not usb and I hated it. Though the motor on mine was pretty consistent I feel like the arm wasn't set up right at the factory. Sadly I didn't realize how much the arm was affecting the sound till I bought a Rega RP1 that was checked and set up properly by the dealer.

 

[drknstrmyknight]

With the demise of Technics, it's too bad that A/T doesn't step up to the plate and IMPROVE their line. They know how to make such great cartridges, golly.
I have a 6 year old AT-120 (non USB) and it's a fine table for the money.
The preamp sn't anything to write home about (I don't use it) but the table is solid, quiet, just does it's job.
The arm on mine was set up properly for the DJ cart they provide and has been relatively easy to set up for the other carts I use on it for previewing used vinly and playing 78's. Maybe I got in before the QC went down.
What they need to do is shore up quality control and come out with a REAL 1200 clone at a higher price point.

 

[Dr Tinear]

With the demise of Technics, it's too bad that A/T doesn't step up to the plate and IMPROVE their line. They know how to make such great cartridges, golly.
I have a 6 year old AT-120 (non USB) and it's a fine table for the money.
The preamp sn't anything to write home about (I don't use it) but the table is solid, quiet, just does it's job.
The arm on mine was set up properly for the DJ cart they provide and has been relatively easy to set up for the other carts I use on it for previewing used vinly and playing 78's. Maybe I got in before the QC went down.
What they need to do is shore up quality control and come out with a REAL 1200 clone at a higher price point.

As long as AT's current line is selling profitably, what motivation do they have to extend it upwards and chase a small, finicky band of audio perfectionists like us? It's not like the higher-end market isn't being served by Pro-Ject, Music Hall and Rega.

 

[majick47]

Audio Technica along with JBL, Altec Lansing and a few other proud old audio mfgs products when found in big box stores and Amazon etc are not the same level of products we once knew and respected. To be competitive in this low end market it is necessary for them to cut every corner they can to bring the item to this price point. Just because a TT resembles a Technics SL-1200 doesn't guarantee it will be built to the same high level of materials/design/performance. Technics has quite a reputation and given the choice they proudly left the TT market heads high and did not attempt to substitute an inferior turntable at a much lower price.