Topping L30 Headphone Amplifier Review

[ZLX]

Did anyone else get an L30 with plug that smells quite bad of chemicals? I've had it airing out for days and it doesn't seem to be getting much better. Also when it's plugged in it seems the heat makes it smell more.

 

[dmac6419]

Had it plugged up for months don't smell a thing,bought It the day Apos Audio sold it.

 

[Vini darko]

Did anyone else get an L30 with plug that smells quite bad of chemicals? I've had it airing out for days and it doesn't seem to be getting much better. Also when it's plugged in it seems the heat makes it smell more.

There's a thread for amp sniffing
https://www.audiosciencereview.com/forum/index.php?threads/noob-amp-smelling.18087/unread
Asr Catering to all audio fetishes

 

[v5cvbb]

Static electricity discharge (ESD) can render the L30 useless in select few instances.

Do we have any evidence this is what's killing L30s? Or is this the current best guess?
I'm unsure about how the anodized aluminum case effects ESD. It's obviously not grounded.

 

[_thelaughingman]

Do we have and evidence this is what's killing L30s? Or is this the current best guess?
I'm unsure about how the anodized aluminum case effects ESD. It's obviously not grounded.

That was my recap of what was being presented a few pages back. At best it’s been guessed by couple other people that it may be ESD, no forensic or actual proof or disclosure from Topping at this point

 

[ZLX]

There's a thread for amp sniffing
https://www.audiosciencereview.com/forum/index.php?threads/noob-amp-smelling.18087/unread
Asr Catering to all audio fetishes

Interesting but it's not the amp itself, the amp is perfect it's the actual plug that came with it.

 

[ZLX]

Had it plugged up for months don't smell a thing,bought It the day Apos Audio sold it.

Weird I can smell it from under my desk and if I put it right up to my nose it's pretty bad. Maybe I got a bad one somehow?

 

[Jose Hidalgo]

So you shared a video with us that you knew to be "useless" as proof that we should debate this issue?

Sort of. For me the reasons for external PSUs have been known for a long time. Given the video title I thought it would explain them in detail, and of course I didn't watch it because I thought it'd say things that would be useless for me. I was in a rush, and my point was just to prove that in 30 seconds I could find material on external PSUs assets. Unfortunately it was clickbait. Had I spent more time I would have found better material. Here's something better : https://www.electronicdesign.com/po...e/21808839/3-ways-to-reduce-powersupply-noise .

Let me put it this way : I have never said that external PSUs were intrinsically "better". They're not. I'm saying that reducing the noise and interference of a PSU is always a difficult task. It's all the more difficult in high-performance products like the Topping ones. The slightest PSU design flaw can show in measurements. External PSUs can help get rid of some of these flaws, just by the mere fact of being external. It's not a "better" solution, but it can get the job done in a number of cases. That may be a reason why they are implemented in a number of systems, including Hi-Fi ones. That's all I was saying.

I'm never interested in having a discussion with someone who grabs the first thing they can find off the internet as evidence of something, even though they know it's a terrible source.

Then by all means, don't. Waste of time for both of us.

 

[half_dog]

@JohnYang1997 Can you tell if the L30 has any plug/unplug TRS connector sensor? These days I've being experiencing a few cut outs from right side. I'm not sure, but I may have isolated the problem to TRS connector. The cut out is "solved" after a few plug unplug cicles with the headphone 's jack - does not matter the headphone, DAC or cables - I have tried different cables, DACs and cables.

 

[JohnYang1997]

@JohnYang1997 Can you tell if the L30 has any plug/unplug TRS connector sensor? These days I've being experiencing a few cut outs from right side. I'm not sure, but I may have isolated the problem to TRS connector. The cut out is "solved" after a few plug unplug cicles with the headphone 's jack - does not matter the headphone, DAC or cables - I have tried different cables, DACs and cables.

May be a failed unit.
Left and right are turned on and off the same time using one relay. There's no sensing circuit for plugging in. Only dc protection that's sensing the output of the amplifier before the relay.

 

[half_dog]

Meeh fork. I will try it out a few more days. I have this unit since october and no problem until this... How should I proceed if occurs that it be a faulty unit? It was bought from AliExpress - Aoshida-HIFI Audio Store.

 

[JohnYang1997]

Meeh fork. I will try it out a few more days. I have this unit since october and no problem until this... How should I proceed if occurs that it be a faulty unit?

Just ask your seller and they will help you out.

 

[half_dog]

Thanks! I should contact them if the problem persists.

 

[iucoen]

Just in case ESD is a problem. Is there any precaution I can take to avoid it? Discharge myself on the E30 before touching the L30? (E30 should be grounded via the USB connector, right?_

Also how does ESD get inside the L30? Via headphone connector, volume knob, or chassis?

 

[raistlin65]

Just in case ESD is a problem. Is there any precaution I can take to avoid it?

Don't use it in the winter months.

Seriously, if ESD is the issue, there will be more instances of it over the next few months, since I would imagine most purchases were in the northern hemisphere.

I would apply some of the same principles that people use when putting PCs together. If you are using it with a desktop computer, ground yourself momentarily by touching a metal part of the chassis when you sit down at your desk, or even better, anytime before you touch the amp. Then don't sit at a desk wearing socks on carpet. Wear shoes. And if you have a wool sweater or polyester shirt that when you wear it in the winter, you tend to shock yourself on stuff, don't wear it.

Of course the ultimate protection would be to wear an anti-static wrist strap when using the amp. https://nerdtechy.com/best-esd-anti-static-wrist-strap

 

[half_dog]

Meeh, the problem just got worst. The right side went mute again around 20 min ago and I am power cycling it and reconnecting the headphone since then. Right side stills muted... I contated Aoshida-HIFI Audio Store and they have being very solicitous so far...

 

[half_dog]

During those power cycles is possible to hear a not so loud pop coming from the right side driver (I'm using a Edifier H840 to test it - the "cheapest" headphone lying around here).

 

[solderdude]

Just in case ESD is a problem. Is there any precaution I can take to avoid it? Discharge myself on the E30 before touching the L30? (E30 should be grounded via the USB connector, right?_

Also how does ESD get inside the L30? Via headphone connector, volume knob, or chassis?

Grounding yourself before touching the L30 should prevent this.

For my job I have to test designs for EMC and ESD.
They 'fire', with a device that actually looks like a gun, on every part of the design that can be touched by hands as well as on inputs and outputs.
In these systems there were also PC's.
One day the system had passed all tests (including the ones that are potentially destructive which is done at the end) and shooting at all points of the PC worked fine. Then the tester decided to shoot at the front of the enclosure at a mechanical lock that holds down a lid and the PC crashed.
It was a grounded lid on a grounded enclosure with no electronic parts inside.
We thought it was a coincidence so after rebooting we tried again. Same happens.
Just a shot at a mechanical and safety grounded part of the enclosure locked up the OS.

The thing with ESD is that the frequency component is very high and can cause a high 'peak' somewhere on the PCB.
Very hard to determine what that path is.

For me the solution was simple. We mounted a wristband to the frame and an instruction on the cabinet to wear the antistatic wristband when servicing the equipment.

 

[Jimbob54]

Grounding yourself before touching the L30 should prevent this.

For my job I have to test designs for EMC and ESD.
They 'fire', with a device that actually looks like a gun, on every part of the design that can be touched by hands as well as on inputs and outputs.
In these systems there were also PC's.
One day the system had passed all tests (including the ones that are potentially destructive which is done at the end) and shooting at all points of the PC worked fine. Then the tester decided to shoot at the front of the enclosure at a mechanical lock that holds down a lid and the PC crashed.
It was a grounded lid on a grounded enclosure with no electronic parts inside.
We thought it was a coincidence so after rebooting we tried again. Same happens.
Just a shot at a mechanical and safety grounded part of the enclosure locked up the OS.

The thing with ESD is that the frequency component is very high and can cause a high 'peak' somewhere on the PCB.
Very hard to determine what that path is.

For me the solution was simple. We mounted a wristband to the frame and an instruction on the cabinet to wear the antistatic wristband when servicing the equipment.

I can see the short term Topping fix now. Free ESD wristband with every order.

 

[pimy]

I can see the short term Topping fix now. Free ESD wristband with every order.

After the ground loop of the A90, it starts to do a lot...