Life span of a Direct Drive Motor, can it die?

ateal

Super Member
I was wondering if anyone knew of anyone who's Direct Drive motor died of either old age, seizure or to high a voltage being used, i.e. 120 v into 100 v.

Just curious as to what would happen if this happened and could it be fixed.

Reason I ask is that there are some really great DD drives from the 1970's and 1980's that people pay a kings ransom for and it would be a crying shame and a hell of an expensive fix if those TT's had the motor die in the near future.

Any thoughts and/or experiences welcome. My question is specifically about the motor only and not all the other bells and whistles which can break down but are reasonably easier to fix or a workaround can be found.
 
I guess the short answer in my case is no. I have several DD tables of that vintage that are still going. The biggest worry is losing an IC chip that is not replaceable.
I'd bet that my heir will need to find a use for some of mine after I am no longer functioning.
 
Oy. The never ending questions about premature deaths of direct drive turntables.

For one thing, the voltage seen by the motor is not line voltage in almost all direct drives, it's produced by the transformer and power supply and driven through an amplifier with a feedback loop for speed regulation. The schematics of the drive systems look not unlike an audio amp.

For another thing, most of them are capable of moving a whole lot more mass than they're called to do in a turntable. As sfox said, burning out an unobtanium IC is more of a concern, but that can be reduced by rebuilding the power supply and making sure it's operating properly.
 
This is encouraging information as I would hate to have a DD motor die as I can imagine it is very expensive fix.

Also, excuse my ignorance but what does the IC chip do and are they in every DD turntable or just ones with auto features.

If they are in every TT where would I start looking for the one associated with my TT.

Thanks.
 
As was said previously, the motor will last forever, the controller may not, however I haven't come across a DD turntable yet that didn't run.

My Technics is modified to run at 78 RPM and it still hasn't died.
 
As was said previously, the motor will last forever, the controller may not, however I haven't come across a DD turntable yet that didn't run.

I have. Both due to dead or dying power supplies. Once that problem was sorted, they were fine. One also had a mess where someone had hacked in an ill-advised remote system which ended up with me actually having to replace a leg on one IC with an old capacitor lead.
 
Only 2 issues I ever saw with Pioneer's DD motors when I serviced them and they were always new enough to be in warranty: a bad Hall sensor (there are usually 3) which would cause the rotor to hunt direction back and forth, and an open frequency generator "FG" circuit trace causing runaway speed. Fix was replace the motor.
 
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Good to know as I just bought another turntable which was not supplied in the US market, only Japan, and it occurred to me that whilst it is working order it may not have been used with a step down convertor in the past. I was therefore worried that if this was the case it may have damaged the motor, i.e. Receiving 120v instead of the 100v rating. Once I receive it I will ensure I use one.
 
Only 2 issues I ever saw with Pioneer's DD motors when I serviced them and they were always new enough to be in warranty: a bad Hall sensor (there are usually 3) which would cause the rotor to hunt direction back and forth, and an open frequency generator "FG" circuit trace causing runaway speed. Fix was replace the motor.

Was the bad Hall sensor in a planar motor or the older core motor?

Sent from my SM-N900V using Tapatalk
 
Was the bad Hall sensor in a planar motor or the older core motor?
Seen failures in both kinds. Once in a while a unit brand-new out of the box would have a defective motor, going berserk back-and-forth or runaway speed. Rarely if ever did I see a bad one that had been in use.

I have spare motors for my PL-L1000, the older "core" type, and also a spare "planar" flat motor used in the PL-L800 I owned years ago. Got rid of that TT, still have the spare motor.
 
Running 100v Japanese turntables on 120v, regardless of their topology is fraught with issues and should never be suggested.

For a start, that 20% extra causes transformers to fail and the extra 20% in secondary voltage prior to the regulators is often sufficient to cause more localised dissipation and failure of the regulator circuitry.

The schematics of DD turntables are not remotely similar to an amplifier.

For one thing, the voltage seen by the motor is not line voltage in almost all direct drives, it's produced by the transformer and power supply and driven through an amplifier with a feedback loop for speed regulation. The schematics of the drive systems look not unlike an audio amp.

For another thing, most of them are capable of moving a whole lot more mass than they're called to do in a turntable. As sfox said, burning out an unobtanium IC is more of a concern, but that can be reduced by rebuilding the power supply and making sure it's operating properly.
 
Seen failures in both kinds. Once in a while a unit brand-new out of the box would have a defective motor, going berserk back-and-forth or runaway speed. Rarely if ever did I see a bad one that had been in use.

I have spare motors for my PL-L1000, the older "core" type, and also a spare "planar" flat motor used in the PL-L800 I owned years ago. Got rid of that TT, still have the spare motor.

I bought a spare motor for my PL-L1000 fairly cheap off the 'bay to insure for Hall failure.

Sent from my SM-N900V using Tapatalk
 
I have a Japanese 100V turntable that was plugged directly into UK 240V mains. The only casualty was a blown fuse! I wouldn't recommend putting this to the test too often, however...
 
I have a Japanese 100V turntable that was plugged directly into UK 240V mains. The only casualty was a blown fuse! I wouldn't recommend putting this to the test too often, however...

Definitely dodged a bullet, it's often the case that a fuse is a 25 cent expendable safety device protected by a $500 component.

Sent from my SM-N900V using Tapatalk
 
Hall sensor issues are very common as the devices are unreliable and deteriorate, often with the black leads of death. Most DDs use one or more hall sensors, often embedded in the coils on the PCB.

Other DDs (akai etc) use optical rotation velocity sensing, with IR led/Photo Tr interrupters and they also fail, as do Sansui with its horrible photo interrupter. Even Denon and Sony's magnetic heads fail as does the imprinted magnetic stripe.

None of these systems will 'last forever'. They are inherently very complicated and will fail way more often than a simple belt drive system.

Technics refined the DD system, with bespoke ICs that have proven themselves in the toughest environments over the longest time. If you want DD AND reliability, I'd go with their TTs.

In my experience repairing every brand I can think of, there's nothing that comes close to the reliability and quality of their DD turntables and arms, from their cheapest ones to the best ones.
 
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I can't be sure it has not been used without a step down transformer, I need to ask the existing owner when I pick it up. If it has been used without a step down its still working. I will ensure to use with a step down once I get it.
 
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