Review and Measurements of Topping DX3Pro DAC and Headphone Amp

[Cidious]

I send my broken board to a fellow audio electronics tinkerer here in my city to play with. Recon pulling wires from the the resistor positions should fix the broken opamp socket. Both he and I will be tweaking our boards. And I'll share here some of my findings. (DO note that I don't have any serious measurement equipment. So most of the modifications will be judged on hearing and is subjective. SORRY. Not a numbers freak anyway... maybe I'm in the wrong place)

Anyway here a photo of the broken board

This was the result of me accidentally pulling a dip8 socket from the board when soldering at night tiredly and impatiently. LOL

Like I said above I also ordered a new DX3 to keep original to test every mod against. I'm burning it in now. Other than that I got my fresh new board from the factory and ordered a seperate display with it. So he and I can quick access our boards without putting it back into the casing.



Today I did the opamp Dip8 socket mod to roll some discrete opamps


I had to do a lot of tuning and measuring to make it fit in the case with this discrete opamp without using extension wires to keep it as close to the board as possible.


My DX3 Pro just went from a €130 device to €200+ adding a €80 euro opamp hahaha. doesn't make sense but at least the opamp won't be holding it back. now looking for more improvements.

Please share your thoughts and ideas on possible mods.

 

[noel_fs]

Does anyone use the DX3Pro on linux? Whenever I stop/start playing something on Linux, there's a faint buzz sounds, and the USB sign flash (which means no signal I think?). How to deal with that?

try wtfplay to see if it still happens, it might be the motherboard itself, or try on a different computer

 

[simonchretien]

Just wondering if anyone has heard a dx3 output to a pair of PSB Alpha PS1? Massdrop is tempting for 160USD, I'm looking for a pair of relatively inexpensive powered speakers. thanks.
Edit: haha nice no shipping to Canada, funny since theyre from Canada.

 

[777]

The power transistors of a phonespeakers amplifier are 2SB649AG

 

[Cidious]

I'm pairing them with QMS Q5 active speakers. they cost me €260. But outperform the Audioengine line up although having some noise floor thingy. Great dynamics and powerfull bass and ribbon tweeter clarity. I'd say the DX3 Pro pairs really well with them giving a bit of an analog feeling here and there. I'd say the ES9018 gives me more soundstage and instrument seperation but less vocality and recessed mids. The DX3 is really nice and neutral and makes the music flow easily without effort but also without the ESS sparkle in the highs.

 

[777]

The standby state issues are comming from a inrush current. It could be possible like ESR of the capacitors is too small and the charging currents are too big, over adapter power supply capability. I tested today with a large range of capacitors and the shutdown in the standby mode is dependent of that. If I rise up the current of the power supply source, everything returns to normal. So, try another power adapter with bigger current rate.

 

[Cidious]

I'm using a 1.5A LPS. Didn't have a single problem before. Just saying the advice above here might be something

 

[gypsygib]

The standby state issues are comming from a inrush current. It could be possible like ESR of the capacitors is too small and the charging currents are too big, over adapter power supply capability. I tested today with a large range of capacitors and the shutdown in the standby mode is dependent of that. If I rise up the current of the power supply source, everything returns to normal. So, try another power adapter with bigger current rate.

Could you explain this in laymans terms, my apologies that I lack the knowledge to understand what you're saying exactly. Are you suggesting a power supply with more amps?

 

[777]

Could you explain this in laymans terms, my apologies that I lack the knowledge to understand what you're saying exactly. Are you suggesting a power supply with more amps?

Yes, more amps.

 

[Pavel]

Pavel, what transformers do you plan to use?

I prefer Chinese transformers. For my taste, they are better than Lundahl.
https://item.taobao.com/item.htm?spm=a1z09.2.0.0.97252e8dFWOHpG&id=572200266555&_u=p2d14s4bb339
or
https://item.taobao.com/item.htm?spm=a1z09.2.0.0.97252e8dH8pGdd&id=39991111619&_u=p2d14s4bc1a0
Both transformers were developed by the same engineer. Yellow and black are very similar in sound. Black is a bit softer, but this is noticeable only when A<->B is quickly switched. The difference is extremely small. Black made better quality.

 

[chrisliuboy]

Anyone could recommend any modification that could make the DX3pro a little bit warmer?....The sharpness when using it with CD900st is killing me, lol.

 

[Yuno]

Anyone could recommend any modification that could make the DX3pro a little bit warmer?....The sharpness when using it with CD900st is killing me, lol.

Install equalizer APO with peace gui and equalize to your preference.

 

[chrisliuboy]

Install equalizer APO with peace gui and equalize to your preference.

Thanks much, will try. Just it has never been this sharp on any other sources, very thin mid-bass to mid with Dx3pro comparing to others.

 

[Yuno]

The standby state issues are comming from a inrush current. It could be possible like ESR of the capacitors is too small and the charging currents are too big, over adapter power supply capability. I tested today with a large range of capacitors and the shutdown in the standby mode is dependent of that. If I rise up the current of the power supply source, everything returns to normal. So, try another power adapter with bigger current rate.

Assuming this is really the cause, what kind of amperage do you believe is required for dx3 pro to not run into standby issue? Based on your testing that is.

 

[777]

Bigger than 1.5 A

 

[AresHarvest]

So this may be obvious to some, but as I set up a DX3Pro for a family member last week, I thought to add some info about the headphone jack. Specifically, about using headphones that have 6.35 mm (1/4") connectors.

We've all seen the inline adapters, but these put undue strain on the jack, which could potentially cause a problem at some point. As a solution, I've found that "pigtail" adapter cables like this one seem to work very well for desktop use, since the shear stress is no longer present at the amp's 3.5 mm jack.

 

[finneybear]

Anyone could recommend any modification that could make the DX3pro a little bit warmer?....The sharpness when using it with CD900st is killing me, lol.

Just add a pair of output transformers listed by Pavel. If this is too much work for you, get this version instead:

https://item.taobao.com/item.htm?spm=a1z10.1-c.w4004-2105892583.6.5757253e0ceZY4&id=578552446942

Transformer is a much better LPF. It will absorb most of the HF noises and give the sound a touch of warmth.
The edginess will be mostly gone. Connect DX3 outputs to the box then the box to your amp.

Those transformers are basically Jensen clones, some versions may even work better:

https://www.ebay.com/itm/Line-Input...ced-Jensen-Transformers-JT-11P-1/361999364033

 

[Barce]

So this may be obvious to some, but as I set up a DX3Pro for a family member last week, I thought to add some info about the headphone jack. Specifically, about using headphones that have 6.35 mm (1/4") connectors.

We've all seen the inline adapters, but these put undue strain on the jack, which could potentially cause a problem at some point. As a solution, I've found that "pigtail" adapter cables like this one seem to work very well for desktop use, since the shear stress is no longer present at the amp's 3.5 mm jack.

This is a valuable message. When I ordered mine the matter of the adapter was my first order of concern - I took one look at the brass socket extender-types and instantly imagined PCB housings being splintered to pieces forever with one false step + critical leverage.

I went with the irregularly expensive Sennheiser part Amazon carries, because I read more than a few reviews of brands like those VCE 3-packs that said they're dirt cheap because they're incredibly touchy and prone to improper channel pickup or only working in certain positions - doesn't seem worth it to cheap out when you don't specifically need a handful of them.

 

[Cidious]

Anyone could recommend any modification that could make the DX3pro a little bit warmer?....The sharpness when using it with CD900st is killing me, lol.

for How long have you been using the DX3? Since I noticed this harshness went away after some proper burn in time. I also experienced this when running just the DAC. Now I run my Lehman as a pre-amp after it which greatly warms it and smoothens the grainyness. I'd recon some output trafos as described here above could be an outcome too. I'll be looking into that too.

Is the AK4493 able to drive trafos directly like the 4497? Else looking into discrete mosfet buffers before the trafos to not suffer from poor lower frequencies.

Other than that Ive just tested the spare board with the sparkoslabs SS3602 discrete opamp. And this is what I conclude after swapping back and forth between OPA1612 and Sparkos.

Sound got more body and warmth. Bass deeper and more controlled. I'd say quite a performance increase in dynamics. The OPA1612 sounds more airy and thinner. The SS3602 is darker but more transparant and intimate. Vocals with the SS3602 are more warm and pronounced. Instrument seperation still good. But not as good as with ESS chips. The OPA1612 is more neutral than the SS3602 but also more clinical. The Sparkos unit just makes it all more warm and musical and deeper bass (which this unit was lacking). All in all it's just a more musically pleasing and engaging sound than the more clinical and distant OPA1612. The SS3602 has a sort of effortless feeling to it. Just flowing and softer. Depending on taste obviously and what you pair it with.


All in all I feel like at least 20% performance increase to my ears. I'm VERY happy I did the mod. It changed the sound signature pleasantly without loosing anything else. It does right to the VELVET sound.

Sidenote: The Sparkos SS3602 needs burning in for at least 100 hours their website states.. I have maybe just ran 10 hours with it. The board is also brand new and needs a few hours of running time to settle. As is I'd already sign for it. But I have a feeling it will all improve more over time. So I'll post back if something changed.

 

[ngs428]

I currently have the Topping DX3 Pro and am considering moving to the Tone Board and Atom amp. I only use USB as an input connection. The random dying of the DX3 has me worried and warranty to China is not realistic.

How reliable is the tone board and is this a wise decision? I like the screen and remote on the DX3, but it isn’t a deal breaker.