Topping L30 Headphone Amplifier Review

[Giangi71]

They are the power supply lines to the OPA.

Could it be, maybe, the AC/AC adaptor the problem?

 

[solderdude]

Could it be, maybe, the AC/AC adaptor the problem?

Highly unlikely. It is just a transformer. The AC is rectified and goes into reservoir caps and then to regulators. Nothing 'fast' gets past the reservoir caps.

 

[Giangi71]

Highly unlikely. It is just a transformer. The AC is rectified and goes into reservoir caps and then to regulators. Nothing 'fast' gets past the reservoir caps.

Correct, eventually the adaptor breaks not L30

 

[artburda]

I can't find my macro lens, but I think I managed to get some more close-up pictures with my phone:

 

[Vini darko]

They are the power supply lines to the OPA.

Thanks , I'm out of ideas then.

 

[solderdude]

I can't find my macro lens, but I think I managed to get some more close-up pictures with my phone:

View attachment 105602View attachment 105603

Looks 'normal'. I think the power supply line is still O.K.
I would suspect the PCB had a short between the via and the trace and is scratched away.
As said, opamps that go defective don't have to show this on the outside. Only measurements can tell if it is defective or not.

 

[BDWoody]

One more incident was reported in another thread. Adding here to keep us updated.

Can anyone pls tell me how to add a user to my message, so that they get a notification?

@PSO ,
Put an @ in front...

 

[Giangi71]

One more incident was reported in another thread. Adding here to keep us updated.

Can anyone pls tell me how to add a user to my message, so that they get a notification?

Azz

 

[enomiss]

Seemed like some sound advice given in good faith.
Maybe take the edge off.

I apologize, wasn't ment personal. I would just not accept ending up with a non stack solution. End of L30 would mean end of E30 for me.
I did a lot of research finding a nice small stack for on my desk that has good availability in Europe. If I can't use L30 anymore, wouldn't know what to do.

 

[filipduarte]

Spoiler: Topping L30 Review

Joshua Valour review already including a "PSA" at the beginning about the failures that have happened with the L30.

 

[Dotcha]

By the way I'm now using headphone output for topping DX7. the reason I bought L30 was that I needed a low-impedance output.
Hope this issue gets fixed well...

 

[enomiss]

On a related note, why do headphones not offer a protection mechanism for receiving bursts of too much voltage (to my understandign this is what blows them up)? Or do some headphones do? Any way to check? And are speakers less sensitive to blow up from this? In short, is there a way to calculate the risk of severe consequences?

 

[threni]

On a related note, why do headphones not offer a protection mechanism for receiving burst of too much voltage (to my understandign this is what blows them up)? Or do some headphones do? Any way to check? And are speakers less sensitive to blow up from this? In short, is there a way to calculate the risk of severe consequences?

Probably impossible for IEMs; would add to the cost and mass of regular headphones.

That aside; is such a thing possible without harming sound quality/sensitivity? And would it necessarily be sacrificial, and need to be sent off to be reset/replaced once it kicked in and saved the drivers? Is there a chance of a false-positive tripping it (ie a fuse)?

 

[kkeretic]

Got an email message/answer today from the local store where I purchased my copy of L30. They informed me that the problem had been noticed with L30 by the manufacturer and that I should stop using it and return the device for service/inspection. They also offer an option to replace it with some other device. I think I’ll go with the A50s.

 

[solderdude]

On a related note, why do headphones not offer a protection mechanism for receiving burst of too much voltage

Actually in the old days the Beyerdynamics had zenerdiodes limiting the voltage.
These days with amps being able to provide high output voltages and currents it would blow up the protection.

The problem in this case is that there is DC (not audible and max power) on the output of the amp.
It would not have to be something catastrophic if the DC protection circuit would have kicked in which alas it doesn't.
When that would have worked it would just not give any sound at all.

 

[trl]

Going back in time and install output caps, like old times.

 

[Pillars]

In another thread, I saw that JDS labs Atom has also affected HPs - hearsay, I have not read any user reporting an incident. At the same time, I have heard very good things about their customer service.

I've not seen any reports on this. Absolutely nowhere near levels of the current L30 issues for sure... or even in the same consideration.

 

[filipduarte]

Got an email message/answer today from the local store where I purchased my copy of L30. They informed me that the problem had been noticed with L30 by the manufacturer and that I should stop using it and return the device for service/inspection. They also offer an option to replace it with some other device. I think I’ll go with the A50s.

I couldn't hold back the wait, I decided to send an email to Shenzhenaudio, where I bought mine L30, asking if they have any information and how to proceed with them since my return period ends tomorrow ...

 

[Giangi71]

I couldn't hold back the wait, I decided to send an email to Shenzhenaudio, where I bought mine L30, asking if they have any information and how to proceed with them since my return period ends tomorrow ...

They told me to use 2011 sn with confidence

 

[Frio]

Well that's pretty optimistic when Mr yang says they made changes in December..