Review and Measurements of Topping DX3Pro DAC and Headphone Amp

[finneybear]

Well, I used to utilize that magic for picking up girls some 30 years ago, but unfortunately it's not the case anymore
What I have left for my autumn years is disassembling broken Chinese devices and blowing wind on them. Now, call it life, if you will...

Btw, DAC is working flawlessly now, regardless of ambient temperature. Moreover, after a minor recap it sounds really great. And I don't mean the whizzing sound of the fan

O man, this is such an ingenious idea! AKM chips in general eat up more power and the 4490 is housed in such a small case with no ventilation.
Probably we should put heatsink on 4493, too? Let's first clean up the power lines though.

 

[yue]

There's no way anyone can recommend this, the amount of dead units and random problems is insane on this device.
I cant even send mine back because the ebay seller has a 20% restocking fee on returns (didnt notice when buying), plus the shipping is way too expensive. I'll have to pray my 200$ bucks device keeps working.
I mean I knew I was buying a chineese product directly, never imagined any product could be this bad.
They should stop selling the unit until they can fix their crap.

@amirm is willing to buy one from those who have a dead device.

 

[finneybear]

Yes, I am also well acquainted with this manufacturer. I bought more than 60 transformers from him. But you bought the wrong model! jensen clone sounds bad. you had to buy exactly what I indicated. This model is called R3.
https://www.audiosciencereview.com/...dx3pro-dac-and-headphone-amp.4967/post-142624

Cidious is getting the same Jayin R3 one. The other E25 is a bit better. In fact, there are even better ones such as PT22. They are expensive and not available through Aliexpress.

 

[finneybear]

The ones in the photo are 10k:10k Jensen clones. I've got a pair even better quality coming in. I got the taobao recommendation from Pavel a bit earlier in this thread. The shop owner is really cool ! And delivers quality and service. He started out cloning buy now his own versions are better quality and after spring festival he has some new products coming. I'll give them a swing.

I worked taobao hard to get the capacitors needed during this spring festival time. And it seems like I've got most of them incoming. The only thing i couldn't get was a 100uf polymer cap for the 3.3V dac power supply. I've got a 220uf though... might squeeze that one in, give it a try if it fits.

I'll replace all the tantalums with polymers kemet co-caps. I found the right sizes and values. And I'll replace the 10uf at the opamp with 33uf ko-cap too.

I would focus on solving the stability problem first. The input power cap, 100uf is definitely too small. The cap at the output side of the first 54331 needs to be replaced by a CDE HAZ as well. This 5V is covering the whole DAC's need.
The decoupling caps around 4493 are barely adequate.

Looks like, based on MacDac's idea, we may have to put a heatsink on top of 4493

 

[finneybear]

Well a mean well 15V 1.66A didn't help, the device shut down in the middle of the game. Was keeping it on A-C too. So this is not the solution.

No no, more current will not solve the problem, especially when you are using a SMPS.

 

[finneybear]

Mine doesn't shutdown. it just stop producing sound in the middle of a track. Apart from that all UI behaves like normal. Rebooting doesn't fix it. One need to Unplug and Replug the power cord to make it work again.

There're also a couple of times it can't play DSD files and need unplug/replug power cord to fix the issue.

Sounds like 4493 had gone to the protection state.

This is the first time Topping putting two high power chips into such a small box. Havent done enough burn in tests, I suppose?

 

[yue]

Sounds like 4493 had gone to the protection state.

This is the first time Topping putting two high power chips into such a small box. Havent done enough burn in tests, I suppose?

not likely. AK chips can operate in 85C degree without issues. mine is far from that.
also the protection logic are made for overcurrent of analog output pins. as long as the pins are not shortened it won't trigger the protection mode.

Unlike computers there's no thermometer in DACs so such logic are not triggered by temperature.


quite a lot of topping products has two dac chips in, such as D50, DX7s, etc.

The NX4 DSD is even more compact. When I got it I was blown away by the nice design.

 

[chrisliuboy]

I would focus on solving the stability problem first. The input power cap, 100uf is definitely too small. The cap at the output side of the first 54331 needs to be replaced by a CDE HAZ as well. This 5V is covering the whole DAC's need.
The decoupling caps around 4493 are barely adequate.

Looks like, based on MacDac's idea, we may have to put a heatsink on top of 4493

Hi Finney, sorry to ask a noob question, what do you think will help to boost the bass on DX3 more? Change the OPA or change the Caps for it? If is the caps, any recommendations? Sorry I knew you mentioned few days ago, I just can't find it in the thread. I was listening to some tracks I familiar with today....I don't know, the sounds how to say..feels no power from bass to mids..

 

[MusicNBeer]

I think the trending data is showing this to be a reliability POS. Mine's going back to Amazon.

 

[Sangram]

The resistance is 1.5K. Enough is enough?

Not really, that's still 1.1mA through the transformer.

Why don't you write to Jensen and ask them if it's OK to have 1.65V across the windings? See what they say as you're simply being mulish about this.

Input, output, mains, coupling, medical, any transformer will NOT work with DC at its input. It's a basic fact that you the great designer seems to be unaware of and persist in propagating untruths. Ask any manufacturer of any transformer anywhere in the world and you will get exactly this answer.

Anyway I'm done replying to you. I've seen enough foolishness in six posts to last me a few lifetimes.

 

[MacDac]

O man, this is such an ingenious idea! AKM chips in general eat up more power and the 4490 is housed in such a small case with no ventilation.
Probably we should put heatsink on 4493, too? Let's first clean up the power lines though.

If (serious) overheating is to blame, then heatsinks alone will not do, I'm affraid. You're probably gonna need to take harder steps, like mounting fans, thermally conductive tapes or heatpipes and drillig holes in the chassis. Or better sink the whole shit in a bowl of some tasty, Chinese peanut oil for perfect heat dissipation. Only if you don't have liquid nitrogen in your cupboard, of course

 

[Cidious]

Yes, I am also well acquainted with this manufacturer. I bought more than 60 transformers from him. But you bought the wrong model! jensen clone sounds bad. you had to buy exactly what I indicated. This model is called R3.
https://www.audiosciencereview.com/...dx3pro-dac-and-headphone-amp.4967/post-142624

And that's the one coming. He had send me the wrong model. But send me the R3 for free. They will arrive today. Thats why I said he is cool

 

[MacDac]

not likely. AK chips can operate in 85C degree without issues. mine is far from that.
also the protection logic are made for overcurrent of analog output pins. as long as the pins are not shortened it won't trigger the protection mode.

Unlike computers there's no thermometer in DACs so such logic are not triggered by temperature.


quite a lot of topping products has two dac chips in, such as D50, DX7s, etc.

The NX4 DSD is even more compact. When I got it I was blown away by the nice design.

Is it possible, that the overcurrent protection mechanism "loses" its logic as a result of thermal overload and triggers the protection mode anyway?

 

[yue]

Is it possible, that the overcurrent protection mechanism "loses" its logic as a result of thermal overload and triggers the protection mode anyway?

it doesn’t feel hot at all.

 

[MacDac]

it doesn’t feel hot at all.

You mean D/A chip or chassis? How about other parts, did you check their temperature?

 

[zephyros]

For those who have problem with the device, can you post the product number (only the first 4 digit is fine, mine is 1812 which means December 2018 batch)? It's on the side of the device with a barcode and DX3 PRO - BLACK or SILVER label. Maybe we can see which batch is problematic.
I got mine from local dealers so return is trivial, fortunately mine doesn't have any problem yet aside from weird interaction with linux (which exist with the D50 anyway).

 

[noobie]

Question... (Cross posting from the DX7s thread because I have the same question with both that and the DX3Pro, and besides, this is where the action is). I am running the DX7s DAC, but I have the same question for my D50 and my DX3Pro... My configuration is Tidal on Windows 10 with Tidal set to play out the Topping in Exclusive Mode...

In the Topping USB Audio Device Control Panel (Windows) there is a format tab. There are two choices - 2 channels, 32 bits and 2 channels 24 bits... What should that be set to? I found mine set to 2 channels 32 bits by default for both the DX7s and the DX3Pro. When I changed it to 2 channels 24 bits the DAC disconnected, but then I reconnected it and it played just fine. There after it stays at whatever I set it to (for that DAC, but is still 32 for the others).

So, my question is, what should this be set to? 24 bits or 32 bits? Does it make a difference?

(I don't think that it matters, but just in case, I have the Windows sound settings set as)

 

[yue]

You mean D/A chip or chassis? How about other parts, did you check their temperature?

I mean DA chips (ak4493) and USB interface chip (xu208). xu208 is a little bit warmer than ak4493 but they are by no means hot. The other parts are hard to get in. One needs a very long hex key to fully open it up so I cannot check.

 

[yue]

For those who have problem with the device, can you post the product number (only the first 4 digit is fine, mine is 1812 which means December 2018 batch)? It's on the side of the device with a barcode and DX3 PRO - BLACK or SILVER label. Maybe we can see which batch is problematic.
I got mine from local dealers so return is trivial, fortunately mine doesn't have any problem yet aside from weird interaction with linux (which exist with the D50 anyway).

mine has 1812.

What problem do you run into on Linux? I don't have any issue with Linux so far. Linux kernel >= 4.18 should fully compatible with it (which means native DSD will be supported). MPD version 0.20.23 should fully work. 0.21.* breaks ARM support for DSD but it should work fine for PCs.

 

[finneybear]

not likely. AK chips can operate in 85C degree without issues. mine is far from that.
also the protection logic are made for overcurrent of analog output pins. as long as the pins are not shortened it won't trigger the protection mode.

Unlike computers there's no thermometer in DACs so such logic are not triggered by temperature.


quite a lot of topping products has two dac chips in, such as D50, DX7s, etc.

The NX4 DSD is even more compact. When I got it I was blown away by the nice design.

You dont need temp sensor here. Just current limit is enough. Before thermal breakdown happens, the current will be out of control. Still, this is just a speculation as we do not know whether 4493 has current limiter built-in.

4493 eats a lot of power, around 250mW, it is 50% more than 4490. AKM probably played the same trick on 4493 as what they did on 4497. Just double the units to make 4493. And the power consumption goes this way... 96K is higher than 44.1K, 192 is higher than 96, etc. So at 384 or 768, the chip can run plenty hot. For big guys such as ES9038 Pro, heatsink becomes crucial:

On the other hand, other Topping machines use mostly mobile ESS chips. They run only 50mW. Very cool to run and no problem with a compact case.