Topping DX5II teardown

[delta76]

People talking of RME like it launches their products flawless. Please, take a look at RME's firmware change logs from 2019 until today.

You cannot compare a unit that launched 6 months ago, with something that has received firmware patches for over 7 years.

Edit: Oh, and not to mention the Hardware rev. X and rev. 7 all over their change log.

And yet they still update software, driver and firmware. You will be lucky if DX5II get any update 1 year after release.
It is impossible to release products without bugs, it is possible and important to keep improving it and supporting it long terms. Especially a product with that many features as RME.

And we can't ignore the topic of the thread. The internal components in DXII is not build to last, and not to repair. That is very important for longevity, and we can say they did not design nor manufacture it with that in mind.

 

[Mutex]

And we can't ignore the topic of the thread. The internal components in DXII is not build to last, and not to repair. That is very important for longevity, and we can say they did not design nor manufacture it with that in mind.

I basically placed this question in here already, but didn't get a proper response.

What component exactly do you see, that you think will not last?

 

[Mocie]

I use my DX5 II every day and have no issues

"Works fine on my machine" is the most low IQ response to anything, without further context. Look into why that might be the case, is it a batch thing? These are the questions and answers you should be providing, rather than the tribalism smugness.

 

[Mutex]

These are the questions and answers you should be providing, rather than the tribalism smugness.

He doesn't need to provide you anything. This isn't the "Help me investigate my DX5 II issues" thread. He gave his feedback as an owner of "My unit works". Take this as a data point and build your own batch-statistics if you like.

Mine also "just works" (not that I have a complicated use-case anyway). Batch 26035*****. Hope this helps.

 

[Berwhale]

"Works fine on my machine" is the most low IQ response to anything, without further context. Look into why that might be the case, is it a batch thing? These are the questions and answers you should be providing, rather than the tribalism smugness.

You selectively quoted half of the first sentence of the paragraph that I wrote. Perhaps you missed the 'further context' in the rest of it?

The rest of your comments make little sense, maybe have a think about what you are trying to convey here.

 

[Mocie]

Mine also "just works" (not that I have a complicated use-case anyway). Batch 26035*****. Hope this helps.

The Batch Number is what I was implying here, that's the extra context needed.

You selectively quoted half of the first sentence of the paragraph that I wrote. Perhaps you missed the 'further context' in the rest of it?

It was more smugging by implying he was in a spiral of disillusionment rather than understanding he was put off by 50+ pages of troubleshooting and breakages, nothing to really consider there.

 

[Berwhale]

The Batch Number is what I was implying here, that's the extra context needed.

It was more smugging by implying he was in a spiral of disillusionment rather than understanding he was put off by 50+ pages of troubleshooting and breakages, nothing to really consider there.

It was a reference to Gartner's Hype Cycle and a joke #toughcrowdtonight

 

[Deleted member 93967]

It was a reference to Gartner's Hype Cycle and a joke #toughcrowdtonight

 

[Whatsthephuss]

Not sure if someone mentioned this already, but does putting an SMPS internally basically guarantee failure after a few years?

Why SMPS fail

home back to articles back to technical explanations back to power supplies published: Jun-17-2014, last edit: Mar-16-2017 Why SMPS often fail after just a few years of service As explained in the …

diyaudioheaven.wordpress.com

Even with my RME Fireface, the internal power supply is what usually fails. Luckily RME has a system in place to replace old power supplies. What are the chances Topping will offer power supplies to repair these units?

 

[arecibo]

It boggles the mind that people can't quite grasp that cheap chinese garbage that measures well is still ... cheap chinese garbage that won't last.

 

[Mutex]

It boggles the mind that people can't quite grasp that cheap chinese garbage that measures well is still ... cheap chinese garbage that won't last.

Right. Please post pictures of the many electronic devices you own that say "Made in USA", starting from your phone please.

 

[arecibo]

Right. Please post pictures of the many electronic devices you own that say "Made in USA", starting from your phone please.

Not everything made in China is "cheap chinese garbage", it depends on the production and manufacturing standards in play. Topping scores quite low on these areas.

 

[Viper780]

Not everything made in China is "cheap chinese garbage", it depends on the production and manufacturing standards in play. Topping scores quite low on these areas.

do you have any examples and numbers from topping?

 

[Bleib]

It boggles the mind that people can't quite grasp that cheap chinese garbage that measures well is still ... cheap chinese garbage that won't last.

Some might be surprised if they looked into western build "high-end" only to see what cheap parts they use inside.
My local hi-fi shop sometimes used to mutter "it uses parts from the 70s inside" about some electronics.
The parts generally are relative inexpensive..

 

[Sokel]

Some might be surprised if they looked into western build "high-end" only to see what cheap parts they use inside.
My local hi-fi shop sometimes used to mutter "it uses parts from the 70s inside" about some electronics.
The parts generally are relative inexpensive..

The ones that use nice parts (or knock-offs of nice parts) usually proudly show them.
There's not enough fake red Wima for example to supply Ali or some trending OPAs ² .

Look at the reviews here, insides are always welcome.

What can't be hidden or faked though are the basics, thermals (it goes hand-to-hand with size at the non-active solutions) and actual size (despite the photo efforts to make them look bigger) .

 

[Bleib]

The ones that use nice parts (or knock-offs of nice parts) usually proudly show them.

Nah, I'd rather wager that most of the high-end crowd do not know the parts at all. It's the marketing, the hopes, fear of missing out, the price etc that plays a role

The insides here is a bit different, there is a bit more knowledge here, but I'd again wager that most don't have the right kind of education to understand most of it

 

[Sokel]

Nah, I'd rather wager that most of the high-end crowd do not know the parts at all. It's the marketing, the hopes, fear of missing out, the price etc that plays a role

The insides here is a bit different, there is a bit more knowledge here, but I'd again wager that most don't have the right kind of education to understand most of it

There's not one single person of the subjective crowd who does not interpret a forest of ELNAs as nice, even if they don't know what a cap does.

What was the thread about the famous green bipolars (not even the brand is needed! ) that changed to Rubycons without mention at the brochure and caused mayhem?
A 3e audio amp of shorts? I don"t remember.

And that was here, at ASR!

 

[MaShu_K]

mine stopped working after less then 2 months. waiting to see if i can get another one but i bought it from china so you never know.
may i ask you how you opened it? i unscrewed 10 screws but it didn't open

I'm in China，mine stopped working after only half a month by a power cutting。I sended it back to topping-official within 2 days and they told me the fuse blew，they replaced the fuse and re-burned MCU firmware ，it's on the way back 。

 

[MaShu_K]

I'm in China，mine stopped working after only half a month by a power cutting。I sended it back to topping-official within 2 days and they told me the fuse blew，they replaced the fuse and re-burned MCU firmware ，it's on the way back 。

and u may need a surge protector

 

[de grave]

@kevin gilmore has the circuit diagram posted here. Here's the full pcb board.


View attachment 467197

First, the digital part


View attachment 467198

You can see the bluetooth module on the top left.
On the middle right is the MS8422N, which is a chip to do routing, replacing LC89058W on earlier topping devices.
The signal then routes to the XMOS for final digital processing (EQ).

On the middle left is the ES9018 DAC. generating analog audio signal and then sending to the synwit processor below.
The Synwit chip will use onboard 12 bit ADC to convert that back to digital signal, and perform the FFT computation.
The FFT bin amplitude will be displayed on the screen as spectrum.

Right side is the I/V module and on the top is the output buffer for RCA using OPA1612.

The power supply is spread across the entire PCB. but below is the main one.

View attachment 467199

Here're the step down converters that generate +/-15V from the switching power supply. There're also mosfets/bjts that control the on/off of the power rails on the top.
the lower right is the headphone protection circuit, by detecting the sum of 4 (2 ch x 2 phase) outputs, so if any transistor fries, it should be able to prevent your headphone from being destroyed.

View attachment 467200

Here you see two I/V boards. Op Amps seem to be OPA1656.
I/V boards are dual sided and the front side can be seen as an improved op amp based on this patent.
once the circuit is simplified to equivalent circuit according to the patent,
what remains is a textbook I/V, identical to op1, r1, r2 and C1 in this article
The back side of the board is just the current source to support the differential pairs on the front side.

Below the I/V boards are the DAC chips and passive output stages.
Topping D50 III has the same board. but DX5 II has twice the I/V.
Each board computes the difference of L+/L-/R+/R- and Ref/2 per DAC.
D50III may omit the Ref/2 or just sum the L/R.

The middle part is particularly interesting. There're multiple transistor pairs. The output of those transistors goes to the I/V board's diff pair input.
So it's the reference voltage for the DAC chip. Based on the transistor counts I am pretty sure it's this patent.
D50 III has the same circuit, by the way. It's safe to assume both devices are designed at the similar time frame (2023).

On the right portion there's +/- 5.8V power rails (half of that shown in the photo), which power the op amps.

In kevin's diagram you can find the transistor pair model.

View attachment 467201

Finally the tiny PCB here is the HP Amp's input and VAS. BJTs are power source, similar to the I/V. The transistor pairs are the input stage (differential pairs).
The input signal is from the bottom motherboard's resistor group, which has the I/V output and HP amp feedback signal, with gain control / mute switches.
The Op Amp (looks like OPA1612) is the VAS. It finally goes to the heat sink on the right (not in the photo) for output.

The output stage is nothing special but a classic class B amplifier. Thanks to the global feedback and tons of compensation it doesn't show any signs of crossover distortion.
The efficiency of the amplifier is also how Topping can cram so much power inside this small box.

Hi. Could you please tell me how to disassemble the DX5 II? I took mine to a repair shop, but they didn't know how to disassemble it, so they refused to repair it.