Topping DX7 Pro DAC and Headphone Amp Reviewed

[Harmonie]

Here's a video of the volume control on mine:

Definitely faulty. The control on my dx3 pro works flawlessly.

I just wonder if there is a bad contact from time to time.
Does it also happen if you use the two fingers, I mean moving the knob perfectly centred so that it may avoid the bad cotact.

 

[SRKRAM]

I just wonder if there is a bad contact from time to time.
Does it also happen if you use the two fingers, I mean moving the knob perfectly centred so that it may avoid the bad cotact.

No, that doesn't make any difference. I usually turn the dial with two fingers, but just did it like that when I filmed.

 

[SRKRAM]

Another thing I've noticed is that the detents (clicks) aren't aligned with the actual steps. In certain positions, moving the volume dial very lightly (without clicking) causes the volume to step up and down. Here's a video of the issue :

On my dx3 pro the volume changes reliability with the clicks.

 

[Jimmy]

I think this unit uses an encoder, this may be a good or a bad thing, good encoders aren't cheap, and cheaper ones sometimes are worse/less reliable than regular potentiometers.

The only way to know what Topping has used would be to open the unit to check it, voiding the warranty. If the malfunctioning has started after some time, and the unit was working OK when brand new, maybe cleaning the part can fix it, but care has to be taken since these components are fragile, here an example is shown :

https://es.ifixit.com/Guía/CMT-CP1+Rotary+encoder+cleaning-replacing/108360

 

[Martin]

I'm having another strange problem with my DX7 Pro. I have mine connected via USB to piCorePlayer on a 2GB Raspberry Pi 4. When I power them on the DX7 Pro does not recognize the connection and I get no sound. The display always shows 22.57MHz when this happens. It usually takes several rounds of powering the DX7 Pro and Raspberry Pi off and on along with unplugging and replugging in the USB cable then suddenly it magically starts working. Any ideas of what could be causing this? Is this an indication of impending death?

Martin

 

[Jimbob54]

I'm having another strange problem with my DX7 Pro. I have mine connected via USB to piCorePlayer on a 2GB Raspberry Pi 4. When I power them on the DX7 Pro does not recognize the connection and I get no sound. The display always shows 22.57MHz when this happens. It usually takes several rounds of powering the DX7 Pro and Raspberry Pi off and on along with unplugging and replugging in the USB cable then suddenly it magically starts working. Any ideas of what could be causing this? Is this an indication of impending death?
View attachment 83830
Martin

Got any other USB sources you can test with? And cables. Rule out the cheaper fixes?

 

[Martin]

Got any other USB sources you can test with? And cables. Rule out the cheaper fixes?

Nothing has changed in quite some time. The problem started a couple of months ago and seems to be getting worse with time. I can try swapping USB cables and using my NUC instead of the Raspberry Pi. Maybe I should keep the Yulong Aquila II just in case it is the DX7 Pro dying.

Martin

 

[Toku]

Here's a video of the volume control on mine:

Definitely faulty. The control on my dx3 pro works flawlessly.

Inexpensive brush rotary encoders are used in many products. The rotary encoder structure has two tracks on a disk-shaped insulating substrate, and slit-shaped electrodes are alternately arranged on the tracks. The rotation position is detected while rubbing this electrode with two brushes.

However, due to such a simple structure, a contact failure occurs in the brush while using it, and the reading of the rotation direction and the rotation step becomes incorrect. It is an inexpensive part and deterioration is unavoidable from the structural viewpoint. The occurrence of this problem depends on how often you use the dial knob. Therefore, I use the remote control without using the knob as much as possible.

To avoid this, use a high-grade magnetic rotary encoder, but this will increase the cost. However, I would like you to use a magnetic rotary encoder if it is a DX7 Pro price rank product.

 

[JohnYang1997]

Inexpensive brush rotary encoders are used in many products. The rotary encoder structure has two tracks on a disk-shaped insulating substrate, and slit-shaped electrodes are alternately arranged on the tracks. The rotation position is detected while rubbing this electrode with two brushes.

However, due to such a simple structure, a contact failure occurs in the brush while using it, and the reading of the rotation direction and the rotation step becomes incorrect. It is an inexpensive part and deterioration is unavoidable from the structural viewpoint. The occurrence of this problem depends on how often you use the dial knob. Therefore, I use the remote control without using the knob as much as possible.

To avoid this, use a high-grade magnetic rotary encoder, but this will increase the cost. However, I would like you to use a magnetic rotary encoder if it is a DX7 Pro price rank product.

Do you have some specific models? The ones I saw are 30+ dollars each. It's only fine if the unit is load with 4493.

 

[Toku]

Do you have some specific models? The ones I saw are 30+ dollars each. It's only fine if the unit is load with 4493.

For example, there are the following products.
The operation is the same as that used for DX7Pro, but it is difficult to use this for DX7Pro because the circuit is different.

https://tech.alpsalpine.com/prod/e/html/encoder/magnetic/em11b/em11b_list.html

 

[JohnYang1997]

For example, there are the following products.
The operation is the same as that used for DX7Pro, but it is difficult to use this for DX7Pro because the circuit is different.

https://tech.alpsalpine.com/prod/e/html/encoder/magnetic/em11b/em11b_list.html

This model is out of stock. Next alternative is bourns which is very expensive.

 

[Harmonie]

Inexpensive brush rotary encoders are used in many products. The rotary encoder structure has two tracks on a disk-shaped insulating substrate, and slit-shaped electrodes are alternately arranged on the tracks. The rotation position is detected while rubbing this electrode with two brushes.

However, due to such a simple structure, a contact failure occurs in the brush while using it, and the reading of the rotation direction and the rotation step becomes incorrect. It is an inexpensive part and deterioration is unavoidable from the structural viewpoint. The occurrence of this problem depends on how often you use the dial knob. Therefore, I use the remote control without using the knob as much as possible.

To avoid this, use a high-grade magnetic rotary encoder, but this will increase the cost. However, I would like you to use a magnetic rotary encoder if it is a DX7 Pro price rank product.

For once, I'm happy to have the D90 and it's 2 volume buttons
Indeed, visually it's less attractive (IMHO)

 

[Toku]

This model is out of stock. Next alternative is bourns which is very expensive.

It is also available at MOUSER, but it is currently out of stock.

https://www.mouser.jp/ProductDetail/ALPS/EM11B16140AE?qs=HXFqYaX1Q2xFXT2bQIItHg==

 

[dsgoen]

I have an issue with the DX7 Pro on Windows 10. In addition to the DX7, I also have some Bower & Wilkens powered speakers with a built-in DAC. When I want to switch from the DX7 to the speakers, Windows reports Speakers (MM-1), but the sound still emanates from the DX7. I have to physically turn-off the DX7 in order to switch. A minor issue, but annoying.

Another issue: I'm using J-River Media Center 26. You have to put your audio device, in my case MM-1 (WASAPI) or DX7 Pro (WASAPI). I know this isn't the right place to ask, but since I'm here: Is there a way to automatically switch between the two instead of entering Tools-->Options every time?

I have always been a little disappointed with my Sennheiser HD 800s. Until now. They sound fantastic with the DX7 Pro. The DX7 is one of my best purchases ever.

I'm planning to use the DX7 Pro as a pre-amp to a Bel Canto power amp to drive a pair of the new KEF LS50 Meta speakers to replace the Bowers & Wilkens. Any comments on the practicality of this?

Thanks.

 

[intelfx]

Question: is DX7 Pro (built-in amp) going to be enough for, say, 600 ohm headphones?

 

[Veri]

Question: is DX7 Pro (built-in amp) going to be enough for, say, 600 ohm headphones?

You can't generalise "600 ohm headphones". What is important is their sensitivity. Which headphones we talking about?

 

[intelfx]

You can't generalise "600 ohm headphones". What is important is their sensitivity. Which headphones we talking about?

"96dB sensitivity" (I assume that's 96 dBSPL/V?) I was talking about Beyerdynamics DT990, but I don't exactly have them, that was just an example. Aren't most quasi-hi-end headphones similar in sensitivity, or does a difference of 10dB mean a lot?

 

[Kaiede]

Ditto with the volume knob on the DX7 Pro I picked up (new) over the summer. It has a mind of its own, sometimes moving 0.5dB per click, sometimes 1dB, sometimes zero. Once it actually moved the volume in the opposite direction than it was turned, astonishingly. Like Martin said, it works flawlessly with the remote but that never gets employed in my near field setup.

Otherwise there are no complaints so the plan here is to simply endure.

I’m noticing that under a specific volume level, it uses 1dB steps. Above that, it uses 0.5dB steps. Somewhere around -50dB I believe (I have to double check). If your setup has you near that boundary, it will definitely feel weird.

I did run into one glitch when I rapidly turned the volume knob where it no longer would reduce volume, only increase it. Had to power cycle the whole thing to fix it. So there’s definitely some fit and finish issues around the volume behavior, including bugs that go beyond the quality of the knob itself.

In terms of performance, this thing is top notch, but I’m starting to see what you pay for when going with something like the ADI or Benchmark DACs Instead.

 

[GD Fan]

I’m noticing that under a specific volume level, it uses 1dB steps. Above that, it uses 0.5dB steps. Somewhere around -50dB I believe (I have to double check). If your setup has you near that boundary, it will definitely feel weird.

I did run into one glitch when I rapidly turned the volume knob where it no longer would reduce volume, only increase it. Had to power cycle the whole thing to fix it. So there’s definitely some fit and finish issues around the volume behavior, including bugs that go beyond the quality of the knob itself.

In terms of performance, this thing is top notch, but I’m starting to see what you pay for when going with something like the ADI or Benchmark DACs Instead.

Good observations, thanks for sharing. -50 is a common number in my arrangement so I'll definitely look out for that phenomenon.

 

[Kaiede]

Good observations, thanks for sharing. -50 is a common number in my arrangement so I'll definitely look out for that phenomenon.

So, I did double-check, and above -50 dB it is 0.5dB steps. Below -50 dB it is 1dB steps.