Topping DX3 Pro+ Review (DAC & Headphone Amp)

[UAN]

The shaft of the mechanical rotary encoder has a click feeling when turned. Depending on the product you are using, the click feeling may vary, but it is a function required for the brush contacts to make correct contact with the electrodes in the specified position.

This means that a better quality encoder is installed in the A30.
I don't like the ratchet encoder in Topping, it feels like a very cheap device.
This DAC also uses a cheap LM4562 instead of the OPA1612 in the Pro V2.

 

[Killingbeans]

This DAC also uses a cheap LM4562 instead of the OPA1612 in the Pro V2.

That must be why it only manages to keep the distortion products of 1KHz below measly -125dB

 

[Doodski]

This means that a better quality encoder is installed in the A30.
I don't like the ratchet encoder in Topping, it feels like a very cheap device.
This DAC also uses a cheap LM4562 instead of the OPA1612 in the Pro V2.

Here is a test @ASR of OP amp rolling.

 

[UAN]

Distortion at a frequency of 1 kHz is not the main parameter for an objective assessment of the quality of an operational amplifier. I don't want to get into theory, but there are more than two dozen parameters. There are many examples of comparison of objective parameters and sound of these operas on the Internet.
I like OPA better. And not only me, earlier manufacturers mainly used OPA, and not the ancient LM. But now there is a crisis, a shortage of components, so you have to save.

 

[Doodski]

Distortion at a frequency of 1 kHz is not the main parameter for an objective assessment of the quality of an operational amplifier. I don't want to get into theory, but there are more than two dozen parameters. There are many examples of comparison of objective parameters and sound of these operas on the Internet.
I like OPA better. And not only me, earlier manufacturers mainly used OPA, and not the ancient LM. But now there is a crisis, a shortage of components, so you have to save.

If the gain, bandwidth/slew rate are similar and exceeding the audio frequency range and no oscillation is present then why would one sound better?

 

[UAN]

If the gain, bandwidth/slew rate are similar and exceeding the audio frequency range and no oscillation is present then why would one sound better?

What about thermal distortion?
They are not easy to measure, but sound quality is greatly affected.

 

[Killingbeans]

Distortion at a frequency of 1 kHz is not the main parameter for an objective assessment of the quality of an operational amplifier. I don't want to get into theory, but there are more than two dozen parameters.

You are preaching to the choir. But parameters that look good on paper don't mean squat if non of it has any audible influence. Implementation is king, IMO.

There are many examples of comparison of objective parameters and sound of these operas on the Internet.

Was those parameters shown to have an effect on something audible, and was the sound comparisons done in any reliable way?

 

[Doodski]

What about thermal distortion?
They are not easy to measure, but sound quality is greatly affected.

LM4562 Average Input Offset Voltage Drift vs Temperature 0.2 μV/°C
OPA1612 VOS over temperature, Typical 1 μV/°C, Max 4 μV/°C
They are different. How much that affects the signal integrity I don't know. I searched for some graphs but did not find any.

 

[Miiman]

Does it work without issue on Windows 11? Not upgrading just yet but thought it would be good to ask if someone tried it.

 

[UAN]

LM4562 Average Input Offset Voltage Drift vs Temperature 0.2 μV/°C
OPA1612 VOS over temperature, Typical 1 μV/°C, Max 4 μV/°C
They are different. How much that affects the signal integrity I don't know. I searched for some graphs but did not find any.

This is the temperature dependence of the static DC parameters. In reality, when the signal amplitude rises and then falls, the temperature of the crystal changes. Thus, the modulation of the parameters by the signal takes place. By ear, this manifests itself as a change in tonal balance. This is very clearly seen when replacing with another type of OA.

 

[UAN]

Was those parameters shown to have an effect on something audible, and was the sound comparisons done in any reliable way?

Can't you hear the change in sound when replacing OA?
Moreover, the measured parameters of the amplifier after replacement are the same.

 

[UAN]

My Pro + has warmed up, the tonal balance has stabilized. Compared to Pro V2, the sound is more neutral and analytical. Of course, this is my subjective assessment. The main thing is that you like it!

 

[JRS]

LM4562 Average Input Offset Voltage Drift vs Temperature 0.2 μV/°C
OPA1612 VOS over temperature, Typical 1 μV/°C, Max 4 μV/°C
They are different. How much that affects the signal integrity I don't know. I searched for some graphs but did not find any.

Maybe the OPA's have a "warmer" sound.

That we are even discussing microvolts of an offset voltage boggles the mind.

 

[Killingbeans]

In reality, when the signal amplitude rises and then falls, the temperature of the crystal changes. Thus, the modulation of the parameters by the signal takes place.

Crystal? Are you talking about the semiconductor substrate?

If you are driving a set of headphones with the opamp and pushing it hard, sure. But when handling line level signals in a DAC? I find it hard to believe.

By ear, this manifests itself as a change in tonal balance. This is very clearly seen when replacing with another type of OA.

By "seen" do you mean listening tests with no controls?

Can't you hear the change in sound when replacing OA?

No. And if I could, I'd suspect oscillations or some other horrible side effect to be the cause... or more likely, expectation bias. I see no reason to replace opamps without specific improvements in mind and verifying these with measurements.

Moreover, the measured parameters of the amplifier after replacement are the same.

So, no changes in the measurements, but yet you still hear a change? And instead of going: "Maybe my head is messing with me... I should do a listening test again, but this time I must design it to rule out perceptual bias", you jump to: "There MUST be something happening that we can't measure"?

Op Amp Measurements

INTRO: In last week’s Op Amps: Myths & Facts article I covered the background for op amps, why they’re important, and some common audiophi...

nwavguy.blogspot.com

 

[UAN]

So, no changes in the measurements, but yet you still hear a change? And instead of going: "Maybe my head is messing with me... I should do a listening test again, but this time I must design it to rule out perceptual bias", you jump to: "There MUST be something happening that we can't measure"?

You are very annoyed ...
I'm sorry...
Thousands of people hear the difference in the sound of OA, Topping went to meet them and in the D50s installed the OA output in the socket.

P.S.This site is for a discussion of measurement, not sound, so let's stop the useless discussion.

 

[Veri]

Thousands of people hear the difference in the sound of OA, Topping went to meet them and in the D50s installed the OA output in the socket.

Citation needed.. It's just to please the enthusiast DIY/modder crowd. Future Topping products so far, none of them support op-amp swapping because it is a silly thing generally downgrading performance.

 

[UAN]

Citation needed.. It's just to please the enthusiast DIY/modder crowd. Future Topping products so far, none of them support op-amp swapping because it is a silly thing generally downgrading performance.

The diyAudio website will help you, "clever".

 

[conuss]

if I could, I'd suspect oscillations or some other horrible side effect to be the cause... or more likely, expectation bias. I see no reason to replace opamps without specific improvements in mind and verifying these with measurements.

So, no changes in the measurements, but yet you still hear a change? And instead of going: "Maybe my head is messing with me... I should do a listening test again, but this time I must design it to rule out perceptual bias", you jump to: "There MUST be something happening that we can't measure"?

Confirm that you consider the audio op-amp market a cynical business, essentially a scam.

 

[JRS]

Confirm that you consider the audio op-amp market a cynical business, essentially a scam.

I don't believe anyone said it was a scam, only that Topping recognized a niche market for those wishing to experiment. Nor does it necessarily prove that Topping agrees that there are significant and readily perceived differences. Nor does it prove that manufacturers are striving to meet the approval of a tiny segment of the market. My guess is that the focus is on reliable, inexpensive products that perform by demonstrating measurable differences in objective measurements without reference to such claims that they typically "sound better" made by a few for the few.

I'd like to see a spec sheet from any of the major op amp manufacturers bragging that they sound better, even while measuring more poorly. .Generally the assumption is that those that measure better will sound better. Yet when it comes to buying amplifiers, there are indeed cases made that some amps sound better despite eschewing what are generally considered as best design practices. Nelson Pass comes to mind. But there it is possible to turn a profit on the sales of a few hundred to a few thousand units whereas I suspect those numbers are a drop in a bucket to what is needed to make money selling IC's.

That said, I suspect the majority of those here are more or less of the belief that there is likely a minimum standard beyond which all these devices sound the same. That's not the same thing, however, as being indifferent to improvements in measured specs known to influence audio performance, namely linear FR along with low noise and distortion. While it may be a matter of "gilding the lily" why not champion ever more faithful designs when there is little difference in price?

 

[Killingbeans]

You are very annoyed ...
I'm sorry...

No worries. Sorry if I had smoke coming out of my ears. The whole "I think I heard something, but it might just be in my head" vs. "I heard something, so it must be true!" -thing is just one of my personal pet peeves.

Thousands of people hear the difference in the sound of OA, Topping went to meet them and in the D50s installed the OA output in the socket.

Topping is just a company comprising human beings. They do their best to make the products attractive to the market segments they are interested in. They are generally a beacon of good engineering, but in the world of supply and demand, they don't mind dipping their toes in facepalm-worthy waters.

Confirm that you consider the audio op-amp market a cynical business, essentially a scam.

There are differences between general purpose op-amps and those designed for audio. Some parameters are more important than others in those applications. But implementation is still king. A really good engineer will be able to design an audibly transparent circuit around a "low-tier" op-amp, and upgrading to a fancy OPA won't be a scam, but it will definitely be overkill. The most fantastic audio op-amp in the world won't help a really bad engineer.

Then there's all of the discrete stuff, like the Burson op-amps, specifically aimed at op-amp rolling. In my book that's just nonsense.. borderline snake-oil.

P.S.This site is for a discussion of measurement, not sound, so let's stop the useless discussion.

It's definitely gone off-topic Back to the DX3 Pro+?