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Topping DX3 Pro+ Review (DAC & Headphone Amp)

anyone subjectively a/b testing this with the old ldac version?
Through speakers, they sound exactly the same to me.
The + remembers volume levels for phones and line out separately which is an improvement. It is also completely muted when switching off, compared to a slight pop with the V2. I really like the orange displays and am not convinced about the blue input indicators on the + - but as that's my biggest concern with the unit, I'm very happy.
The volume encoders work well on both my V2 and +, although I'm aware that they can be fragile and use the remote almost all the time.
There were no issues swapping over - it was literally a matter of removing all the connections from the back of one and putting them into the other. Audio from PC (ASIO) over USB, TV (Sharp) over optical and phone over Bluetooth all just worked. My android phone won't tell me what codec it uses, irritatingly but it's better than 'basic' bluetooth, same on both and definitely fine for background music.
I did plug headphones in and I need to be careful here - I'm not a big headphone listener and I just tried the headphones at the end to check that the headphone amp was working, so I didn't even listen to the V2 and then swap over to the +, let alone any proper blind test. Also the headphones are AKG K361 (nominally 32ohm) which are nothing very special. But I did feel like the + sounded better - more bass clarity and perhaps more bass altogether. I'd been a bit disappointed with the 361s and perhaps it was the V2 all along. I certainly feel a lot more like listening to headphones now. Or perhaps my perception is playing tricks and it just sounds better because it's new. Then again, as my expectation was that it would be the same, this is contrary to confirmation bias.
 
Through speakers, they sound exactly the same to me.
The + remembers volume levels for phones and line out separately which is an improvement. It is also completely muted when switching off, compared to a slight pop with the V2. I really like the orange displays and am not convinced about the blue input indicators on the + - but as that's my biggest concern with the unit, I'm very happy.
The volume encoders work well on both my V2 and +, although I'm aware that they can be fragile and use the remote almost all the time.
There were no issues swapping over - it was literally a matter of removing all the connections from the back of one and putting them into the other. Audio from PC (ASIO) over USB, TV (Sharp) over optical and phone over Bluetooth all just worked. My android phone won't tell me what codec it uses, irritatingly but it's better than 'basic' bluetooth, same on both and definitely fine for background music.
I did plug headphones in and I need to be careful here - I'm not a big headphone listener and I just tried the headphones at the end to check that the headphone amp was working, so I didn't even listen to the V2 and then swap over to the +, let alone any proper blind test. Also the headphones are AKG K361 (nominally 32ohm) which are nothing very special. But I did feel like the + sounded better - more bass clarity and perhaps more bass altogether. I'd been a bit disappointed with the 361s and perhaps it was the V2 all along. I certainly feel a lot more like listening to headphones now. Or perhaps my perception is playing tricks and it just sounds better because it's new. Then again, as my expectation was that it would be the same, this is contrary to confirmation bias.
Thanks. The speaker pop is certainly annoying on the v2 for me as well. I suspect it would be hard to distinguish between them on speakers.
I'm curious about headphones output. I have k371 which is similar to yours. However, I also have he400i which feel somewhat lacking on v2 (when a/b testing with more powerful amp at regular listening level). Even though, on paper, v2 power should be plenty.
The + seems to up in power, so I wonder how it does with more demanding planar.
 
However, I also have he400i which feel somewhat lacking on v2 (when a/b testing with more powerful amp at regular listening level). Even though, on paper, v2 power should be plenty.
The + seems to up in power, so I wonder how it does with more demanding planar.

As noted earlier, I have HE400i 2020 and DX3 Pro+. Even with some bass boost EQ, the power is not lacking at all for as loud as I can stand it (which of course varies by person). On the other hand, the HE400i is somewhat lacking with my previous iFi amp (which I still use in portable situations). Even though it too can get loud to the point of discomfort, something is missing in the bass and overall scale and impact with higher volume levels on the iFi. Though to be fair, I don't have another amp similar to the DX3 Pro v2 to compare.
 
Thanks. The speaker pop is certainly annoying on the v2 for me as well. I suspect it would be hard to distinguish between them on speakers.
I'm curious about headphones output. I have k371 which is similar to yours. However, I also have he400i which feel somewhat lacking on v2 (when a/b testing with more powerful amp at regular listening level). Even though, on paper, v2 power should be plenty.
The + seems to up in power, so I wonder how it does with more demanding planar.
This was my one concern having enough power to properly drive Sundara's. All of the recommended EQ suggests 8dB is needed for bass boost, so giving up 10dB to accommodate that left me with just enough power to get really loud, but still wish I had even 3dB more. More importantly, I never felt as if things were becoming unglued or harsh, so I am very happy. The extra power, however beguiling, isn't in the interest of my long term hearing health, so I'd say it's a perfect match.
 
This was my one concern having enough power to properly drive Sundara's. All of the recommended EQ suggests 8dB is needed for bass boost, so giving up 10dB to accommodate that left me with just enough power to get really loud, but still wish I had even 3dB more. More importantly, I never felt as if things were becoming unglued or harsh, so I am very happy. The extra power, however beguiling, isn't in the interest of my long term hearing health, so I'd say it's a perfect match.
For my ears i dont need more either. Especially since i listen for quite a long while at a time. There is that high gain mode on the amp but i would guess the noisefloor rises as well? Looks good on Amirs graphs so i guess its not problem unless hitting clipping levels?
 
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In my experience, v2 is plenty loud on he400i but mid is slightly pushed back. My listening level is -30 to -26 at low gain. I've never felt bass is lacking. Hopefully, the extra power of the + can push the mids to more balanced level.
 
Thanks a lot, very informative. Useful to remember next time I go fishing for audio equipment (especially if something more pricey).

I perfectly understand that building devices like DX3 Pro+ requires lots of compromises. It is just sucks that you can observe the problem practically from the get-go.

Out of curiosity - judging from your posts history/profile I would assume that you may be in position to answer such a question - can you provide any ballpark estimation how much expensive the device would be if Topping used magnetic or optical rotary encodes? I assume it primarily boils down to the costs of materials and design and then manufacturing challenges/complexities.
You have a large collection of DACs. Which one of them has a properly working knob?
Unfortunately all products are the same.
This issue is not unique to audio equipment. Mechanical rotary encoders are used in various devices and I have experienced many troubles so far.
There is a big difference in quality between manufacturers of mechanical rotary encoders, and we have no choice but to ask Topping to select and use products of good quality.
Better products naturally have higher prices. I think that the ones currently used for Chinese products have a parts unit price of about $ 2. If this is a magnetic rotary encoder, the unit price of parts will probably be over $ 20. In addition, peripheral circuits will become complicated, which will greatly increase the cost. But my desire is to choose a higher quality rotary encoder for DX7 Pro class products.

I am fully aware of the drawbacks of mechanical rotary encoders, so when I can use a remote control, I try not to operate with knobs as much as possible.
 
Thanks again, with that and few more searches about rotary encoders I have a bit better understanding of the problem.

That said, I'm finding this rather unacceptable. There is nothing in the DX3 Pro+ manual about 'hey, the volume knob may be malfunctioning from the get-go because we use a cheap encoder' or 'please try to use the remote to control the volume level exclusively'. Topping is selling a device with the volume knob which should work correctly. If they are aware that the encoder they choose to put into DX3 Pro+ is of such a low quality it is shame on them. Maybe me or Miiman are just got unlucky, dunno, honestly judging from your posts one should be in wonder that the volume knob works at all (I'm exagerrating a lot obviously).

Using the remote is all and dandy, but I suspect that many people plan to use DX3 Pro+ as the desktop DAC & headphone amplifier. If I want to quickly adjust the volume it is easier to me to quickly reach for the knob which always stays in the same place than look for the remote (which may be somewhere on the left, or somewhere on the right, or maybe on the top of the speaker).

I will be contacting Topping about this problem and depending on what's their take I will think what's next. Personally I expect the device I'm buying to work without any problems at least for the first 2-3 years.

Thanks for the info about prices. Now, for me I would be OK with the price being $30 more (just guessing based on the numbers you provided) if I was aware of the problem and manufacturing/design choices. Assuming that it would give me a reliable volume knob (how long a magnetic rotary encoder is supposed to last?). But then it is like +15% of the current price so other more cost-conscious people could hesitate with purchasing this device.

If anyone wonders no hard feelings for Amir ;-). I've seen him few times clearly expressing what is the focus of his reviews and if anyone wonders about other aspects of tested products one should check other sources/wait for info from other users. I was also aware about the risk of ordering from ShenzhenAudio - I was just itchy to have something with the volume knob after replacing my old speakers with KRK's, as well as not having plug the headphones in and out. If I got something 'fulfilled by Amazon' I would probably just shrug my shoulders now and order new device or request my money back (although for now I would rather avoid trying to find another product...). Well, tough luck...
 
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Thanks again, with that and few more searches about rotary encoders I have a bit better understanding of the problem.

That said, I'm finding this rather unacceptable. There is nothing in the DX3 Pro+ manual about 'hey, the volume knob may be malfunctioning from the get-go because we use a cheap encoder' or 'please try to use the remote to control the volume level exclusively'. Topping is selling a device with the volume knob which should work correctly. If they are aware that the encoder they choose to put into DX3 Pro+ is of such a low quality it is shame on them. Maybe me or Miiman are just got unlucky, dunno, honestly judging from your posts one should be in wonder that the volume knob works at all (I'm exagerrating a lot obviously).

Using the remote is all and dandy, but I suspect that many people plan to use DX3 Pro+ as the desktop DAC & headphone amplifier. If I want to quickly adjust the volume it is easier to me to quickly reach for the knob which always stays in the same place than look for the remote (which may be somewhere on the left, or somewhere on the right, or maybe on the top of the speaker).

I will be contacting Topping about this problem and depending on what's their take I will think what's next. Personally I expect the device I'm buying to work without any problems at least for the first 2-3 years.

Thanks for the info about prices. Now, for me I would be OK with the price being $30 more (just guessing based on the numbers you provided) if I was aware of the problem and manufacturing/design choices. Assuming that it would give me a reliable volume knob (how long a magnetic rotary encoder is supposed to last?). But then it is like +15% of the current price so other more cost-conscious people could hesitate with purchasing this device.

If anyone wonders no hard feelings for Amir ;-). I've seen him few times clearly expressing what is the focus of his reviews and if anyone wonders about other aspects of tested products one should check other sources/wait for info from other users. I was also aware about the risk of ordering from ShenzhenAudio - I was just itchy to have something with the volume knob after replacing my old speakers with KRK's, as well as not having plug the headphones in and out. If I got something 'fulfilled by Amazon' I would probably just shrug my shoulders now and order new device or request my money back (although for now I would rather avoid trying to find another product...). Well, tough luck...
If your DX3Pro+ has just been purchased and you already have such symptoms, it is clearly defective. Please consult your dealer for exchange or return.
 
And what kind of encoder is there? Details, please.
There are a great variety of rotary encoders. It is sold by various manufacturers only by mechanical type. There are many manufacturers in Japan where I live.
Search the web for mechanical rotary encoders, optical encoders, and magnetic encoders. At the same time, there are many explanations about its structure, so you can understand it.
The difference between the three types is that mechanical rotary encoders do not require a power supply, while optical and magnetic encoders do.
I wouldn't recommend it if you're thinking of modifying the product you have. Finding the perfect match is hard.
 
The poor quality of the Pro + encoder worries me too. The Loxjie A30 ($ 180) also has an encoder, but it rotates very smoothly and silently. The Topping has a dangling control knob and a strong crackle when rotating. It seems that he will soon break.
 

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I suspect the price is much lower. I just looked at Digikey and found many manufacturers (including Bourne) which offer a range of number of products (incremental, 20 or more increments/revolution--best I can tell, ours is 32) in the 2 to 4 dollar range that are expected to survive 30,000 or more revolutions. So I suspect it's a bad batch.

FWIW I just got mine and it is working fine. I am not defending Topping, just trying to add some more data to the issue.
 
The poor quality of the Pro + encoder worries me too. The Loxjie A30 ($ 180) also has an encoder, but it rotates very smoothly and silently. The Topping has a dangling control knob and a strong crackle when rotating. It seems that he will soon break.
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.
The rotary encoder used in DX3 Pro + has a strong click feeling, but the rotary encoder used in the SMSL Group products has a weak click feeling.
If you don't feel a click and it rotates smoothly, you are using something other than a mechanical rotary encoder.
 
Are you absolutely certain it's a mechanical problem with the encoder? I'm still leaning towards compromises in the firmware causing the "issue". It could be a debounce code that lets a click slip now and then, or polling done in a way that gives the same unfortunate leeway.
 
Hi,
That's probably a dumb question, but there's one one setting I can't clearly understand. While using the USB input, if I press the headphone button on the remote, 0-2 symbol is shown, DAC symbol is turned off in the display and volume goes down slightly....

According to the manual, 0-2 and 0-3 setting has to do with enabling line out....

Why is the DAC logo turned off in the display in O-2 mode?

Thanks.
 
Have a look at the manual again, O-2 is the headphone output and O-3 is both headphone and line-out outputs. For each of these three modes (O-1, O-2, O-3) the device maintains (remembers) a separate volume level.

And I don't think it is related to the USB input itself - output modes should work the same for any input mode (personally I've tested USB and BT).
 
Have a look at the manual again, O-2 is the headphone output and O-3 is both headphone and line-out outputs. For each of these three modes (O-1, O-2, O-3) the device maintains (remembers) a separate volume level.

And I don't think it is related to the USB input itself - output modes should work the same for any input mode (personally I've tested USB and BT).
Thanks, I get then the volume thing.... what about the DAC logo going off in 0-2?
 
Thanks, I get then the volume thing.... what about the DAC logo going off in 0-2?

Yeah, it is a bit confusing. I think that it is best to think about the 'DAC' indicator as 'the line-out (RCA) output is active' and the headphone indicator as 'the headphone output is active'.

Why is it called 'DAC'? I don't know. To add even more confusion for the line-out output you have two 'submodes', one named 'DAC' and the other (the default one) 'Preamplifier' in the manual. You can switch between these two modes using the setup menu only. I think the only difference between them is that in 'DAC' mode the volume is fixed at 0dB (beware and protect your ears ;-)).
 
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