Review and Measurements of Topping DX3Pro DAC and Headphone Amp

[finneybear]

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..

Well, just got my DX3 three hours ago! DId a quick test with HD600... and the sound.... is awful!!!! LOL

Yeah, no mid-bass. Shrill and dry on top. Now I know what people were complaining about. Good side is it has decent image, good instrument separation, etc. I can see how it got good measurement numbers. At the same, the test just matched what I had been worried. Those small spikes around 1KHz would make all the troubles. Definitely does not sound like AKM 449X, nor like 1612. Will do test with DSD512 to see whether there's any change. Next will let it run for 200 hours then start to figure out how the LPF is done.

 

[yue]

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:
View attachment 21008

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.

those are just myths. If you take a look at Oppo Sonica DAC implementation there's no heat sink on top of ES9038Pro at all.
LKS is just a hoax like audio-gd who makes pretty looking PCBs.

And I said above that the AK chips are very cool when the audio gets cut. Usually even if they run DSD512 they still keep cool

 

[finneybear]

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.

LOL The transformer can easily handle 10-15mA.

DC isolation/line transformers are widely used in telecommunication industry. As mentioned above, tube amp uses transformers and the DC bias can be in the range of a few hundred volts.

So how about I declare you as the winner? Will this make you happy now? LOL

 

[finneybear]

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

No no, I want to keep it decently hot. Hot machines sound better. This is what Nelson Pass said.

 

[finneybear]

those are just myths. If you take a look at Oppo Sonica DAC implementation there's no heat sink on top of ES9038Pro at all.
LKS is just a hoax like audio-gd who makes pretty looking PCBs.

And I said above that the AK chips are very cool when the audio gets cut. Usually even if they run DSD512 they still keep cool

No no no, LKS did not have heatsink originally. It was installed later when people complaining the chips got really hot. That company is really different from audio-gd, BTW. LOL

Sonica was an early design for 9038 pro. A lot of things were not learned yet. Later the company simply abandoned the product.
That machine has good measurement numbers yet sound overwhelmed. I sold it in one week.

 

[finneybear]

those are just myths. If you take a look at Oppo Sonica DAC implementation there's no heat sink on top of ES9038Pro at all.
LKS is just a hoax like audio-gd who makes pretty looking PCBs.

And I said above that the AK chips are very cool when the audio gets cut. Usually even if they run DSD512 they still keep cool

BTW, DSD is different from PCM. DSD will by-pass the DSP, PCM to bitstream conversion stage inside 4493. It actually may not run as hot.

 

[Wolven]

Well, just got my DX3 three hours ago! DId a quick test with HD600... and the sound.... is awful!!!! LOL

Yeah, no mid-bass. Shrill and dry on top. Now I know what people were complaining about. Good side is it has decent image, good instrument separation, etc. I can see how it got good measurement numbers. At the same, the test just matched what I had been worried. Those small spikes around 1KHz would make all the troubles. Definitely does not sound like AKM 449X, nor like 1612. Will do test with DSD512 to see whether there's any change. Next will let it run for 200 hours then start to figure out how the LPF is done.

I didn't see any complaints about the sound quality (one person thinks little bass is present), perhaps I have missed some posts.
Most people seem to like the sound. Then again I have not tried DX3pro with HD600, sounds fine with HE400i but those headphones are lean on bass, no hint of harshness. My speakers are happy, the bass may sound lighter although I have attributed it to a cleaner sound.
At the start I equalized the sound a little, but have since stopped.
Can you mention some songs where you found lack of mid-bass and shrill? I would like to try those songs in my setups.

 

[yue]

It was installed later when people complaining the chips got really hot.

A good proof that they don't know how to design correct circuit so they can only come up with a heat sink to solve a problem that simply shouldn't exist in the first place.

Sonica was an early design for 9038 pro. A lot of things were not learned yet.

I would rather trust Oppo designers. They worked in the same area as the ESS guys a few blocks from my home and they shared a lot of information.

Later the company simply abandoned the product.

Not because of the product at all. They just shut themselves down as they believe hifi and bluray will eventually becomes an irrelevant market.
Mobile is a more lucrative and fast growing market after all.

 

[finneybear]

I didn't see any complaints about the sound quality (one person thinks little bass is present), perhaps I have missed some posts.
Most people seem to like the sound. Then again I have not tried DX3pro with HD600, sounds fine with HE400i but those headphones are lean on bass, no hint of harshness. My speakers are happy, the bass may sound lighter although I have attributed it to a cleaner sound.
At the start I equalized the sound a little, but have since stopped.
Can you mention some songs where you found lack of mid-bass and shrill? I would like to try those songs in my setups.

I did a quick A/B test between DX3 and my bedside tablet system - a lowly ES9018K2M DAC with a cheap SMSL TPA6120 based headphone amp.
The 9018 can dance around DX3. Ok, ok, DX3 has better image/stage. The 9018 had gone through mods with better caps, a femto second clock, film caps for LPF, and one OPA2228. The headphone amp is pretty much stock.

I am not saying DX3 is bad as this is still too early to tell though I can see why some people would complain about it. I do feel this machine has a lot of potentials, in fact. Need to burn it for 200 hours before making the nest step.

 

[finneybear]

A good proof that they don't know how to design correct circuit so they can only come up with a heat sink to solve a problem that simply shouldn't exist in the first place.


I would rather trust Oppo designers. They worked in the same area as the ESS guys a few blocks from my home and they shared a lot of information.


Not because of the product at all. They just shut themselves down as they believe hifi and bluray will eventually becomes an irrelevant market.
Mobile is a more lucrative and fast growing market after all.

Another No no no here. Hot 9038 Pro has nothing to do with good engineering or not. This thing is hot as it can output current as high as 100mA. Datasheet does not mention it hence nobody cares about it. Sonica's 9038 Pro runs very hot, too! One of the reasons I dumped it. ESS engineers may think it's OK yet LKS just wants their customers to be worry free.

Actually I got to know the chief designer of the ESS chip. When the first 9018 just came out, we were in such a heated discussion, he even asked me whether he should show me the Verilog codes. LOL

 

[Wolven]

I did a quick A/B test between DX3 and my bedside tablet system - a lowly ES9018K2M DAC with a cheap SMSL TPA6120 based headphone amp.
The 9018 can dance around DX3. Ok, ok, DX3 has better image/stage. The 9018 had gone through mods with better caps, a femto second clock, film caps for LPF, and one OPA2228. The headphone amp is pretty much stock.

View attachment 21010

I am not saying DX3 is bad as this is still too early to tell though I can see why some people would complain about it. I do feel this machine has a lot of potentials, in fact. Need to burn it for 200 hours before making the nest step.

You are killing me. I went back to the saved equalization settings from the day I got DX3pro, and guess what my first impression apparently was:: increase everything under 600Hz, roll of the highs. I just put those settings back on and yeah, its' better. I was reading somewhere that AKM chips with the velvet sound have typical japanese sound signature as in recessed mids and exaggerated highs, not sure if that's true. I'm going to hookup my Denon which has high end AKM chip and see if there is a difference.

 

[777]

After one hour of music on RCA-pre output, with pre at -25dB, both AK4493 had the temperature around 35C-40C. Ambient temperature is 22C. May be wrong but AK4493 does not seem to have temperature problems.

 

[Cidious]

After one hour of music on RCA-pre output, with pre at -25dB, both AK4493 had the temperature around 35C-40C. Ambient temperature is 22C. May be wrong but AK4493 does not seem to have temperature problems.

It doesn't have heat problems. It runs cool enough. Might be other issues though. I sometimes get into trouble when going to another track or skipping within a track.. hear the click inside and need to wait a few seconds and restart the song.. hardware.. or software. hard to say.

For the rest I have to admit that my LKS 9018 is better in some areas of refinement. sounding more smooth overall and more holographic but the potential of the AKM having more detail and imaging is definitely there.. I think with some mods the AK4493 chips will be able to sound very decently.

 

[y845133y]

I changed the DX3-PRO's output capacitors to KO-CAP 150uf. The low frequency has improvement.

Using the KEMET SIM tool for checking KO-CAP 150u and Tantalum CAP 33u as below. We can get lower impedance and ESR from 100Hz to 100kHz.
If the AK4493's output doesn't have noise which is from 20kHz to 100kHz or more, change the capacitor will have more cleaner sound.

 

[simonchretien]

You are killing me. I went back to the saved equalization settings from the day I got DX3pro, and guess what my first impression apparently was:: increase everything under 600Hz, roll of the highs. I just put those settings back on and yeah, its' better. I was reading somewhere that AKM chips with the velvet sound have typical japanese sound signature as in recessed mids and exaggerated highs, not sure if that's true. I'm going to hookup my Denon which has high end AKM chip and see if there is a difference.

Mostly using my HD6XX with it, sound is pretty good.
So even considering my negative rambling about the unit I like the unit

Got a reply from Topping, their solution is to send it back to the seller, oh yeah I'll surely pay 45$ for air shipping plus 40$ of restocking fee lol.

They say they dont have any problematic unit so they cannot test or do anything about it yet...

 

[Cidious]

That's interesting. I just checked for the 100uf parts that I ordered.

 

[Yuno]

Got a reply from Topping, their solution is to send it back to the seller, oh yeah I'll surely pay 45$ for air shipping plus 40$ of restocking fee lol.

They say they dont have any problematic unit so they cannot test or do anything about it yet...

I assume your issue is phantom shutdowns? Personally I had 3 since I bought my unit on 11.11, last one 3 days ago. It's quite bizarre, not a big deal overall, but I would like this thing not to die on me, and those shutdowns as you say don't seem normal.
Just got my mean well 1.66A psu today (GS25A15-P1J) but that apparently does nothing anyway, oh well.

 

[777]

I don't understand why you want ultra-low ESR in the signal path.

 

[ChuckT]

Yea babe, we have the music now

Ha ha, I did exactly the same. I replace all 8 tan caps with the green Nichicon Muse ES. And I removed the 2 tan cap and 2 ceramic caps around opa1612 and replace with a small value Nichicon KZ. It brought a more organic sound to the dac where before it has a relatively clinical sound.

 

[ChuckT]

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..

I remove the ceramic and tan caps for decoupling opa1612 and put in a Nichicon KZ.