Review and Measurements of Topping DX3Pro DAC and Headphone Amp

[amirm]

To be clear, the second set of image I posted was with a hair drying on hot setting close to the board to elevate its temps. The actual conditions without that are in the first post which are much, much cooler. And that is with a severe load.

 

[mikehoopes]

My speculation now is those no brand e-caps ripple current drops fast along the rise of temperature. When temp drops, those caps work fine again. Then it will also depend on where those bad caps are. Amir's thermal shot shows caps are relatively cool though.

Anyway, wait until I get a chance to measure those caps.

On the flip side, I recall e-caps in simple-switcher power supplies whose ESR would drop when you pointed a heat gun at them. A dead switcher would come back to life until you withdrew the external heat source. That was a quick test for non-functioning LCD monitors; nine times out of ten it was prematurely-aged e-caps on the SMPS output. I’d replace them with Panasonic FM series or equivalent.

 

[yue]

I will take one with those symptoms too but yes, a completely broken one may be better.

You can send messages to those who run to this issue a lot.
for instance, reddit
or

(posted by our forum member @exaudio)

 

[chrisliuboy]

1808, ~2 hrs/day, 60% headphone. No issues so far.

Same 1808 here, ~6 hrs/day, mixed use, about 1 random shutdown per month. No other issues.

 

[splkn]

Still have not got my long hex key to pull up the main board yet.

Where can I buy this key?

 

[finneybear]

Where can I buy this key?

eBay. 2mm by 200mm hex t handle

 

[pejakovic1]

Can we also know for those that experience random shutdowns if they have topping drivers installed?
I had a few random shutdowns (totalling 4) and I do have the drivers installed. Owning the device since mid december.

 

[yue]

Can we also know for those that experience random shutdowns if they have topping drivers installed?
I had a few random shutdowns (totalling 4) and I do have the drivers installed. Owning the device since mid december.

Not related to topping driver. Some people have random shutdown in Linux as well. Some experienced it using spdif so not even usb related.

 

[splkn]

Can someone explain how in DX3Pro they get -10v?

 

[SiW]

@amirm what date is shown on the label of your unit?

Mine is 1808 and no shutdown...yet!

 

[pacman]

1808, 1 month of use, about 4 hours of active use per day, half on DAC, half on headphone amp. The PC runs 24/7 and noticed 1 single standby shutdown while the unity were iddle.

 

[y845133y]

Can someone explain how in DX3Pro they get -10v?

The 15v input to dual buck circuits can output two 10v. Then first 10v's negtive electrode (-) connects to second 10v's positive electrode (+) as below. The second 10v provides the -10v.View attachment 21167

 

[splkn]

The 15v input to dual buck circuits can output two 10v. Then first 10v's negtive electrode (-) connects to second 10v's positive electrode (+) as below. The second 10v provides the -10v.

Is the input ground disconnected from the output ground?

 

[bravomail]

since I have a degree in radio engineering, I'll tell u that there is no point in capacitors or resistors rolling, unless u change the value of capacity or resistance. Those both are passive elements and the way they made will not change your sound or measurement.

 

[Pavel]

eBay. 2mm by 200mm hex t handle

I can not find. Can you provide a link to the product?

 

[wchens]

1812 here too. Thanks Amirm for the effort and recommendation for this cute DAC/AMP
- Started using on 4/1/19,
- 5hrs per day usage
- No topping drivers are installed
- Using currently for connecting to my Audio Engine 2 only via RCA
- Turn off my dac/amp and power off after usage
- No Auto shutdown, standby mode encountered yet

Clicking issue happen only when I manually changed the sample rate


*****Update on 18 Mar 19******
- Few days ago I accidentally pressed the volume knob to switch from DAC to OPT (instead of powered off) and when I switch it back to DAC mode, the volume of my speakers suddenly went very loud.
- Encountered no sound on my right channel Audio Engine 2 sometimes but after I switch off and on DX3 pro, it seems to resolve the issue.
- Not too sure whether my DX3 pro or my Audio Engine 2 speakers are fried due to the sudden change in volume spike.

 

[y845133y]

[QUOTE =“splkn，post：145507，member：5632”]輸入接地是否與輸出接地斷開連接？[/ QUOTE]
一世

Is the input ground disconnected from the output ground?

The +/-10v power is provided to op amp and headphone amp. Those device's ground is disconnected with input ground.

 

[Rollingsound514]

OK, I cooked it and cooked it good:

EDIT: this is after a hairdryer on hot setting raised the temps to see if anything fails:

View attachment 21140

As you see temps are now nearly 70 degrees C. The unit operated perfectly and continues to do so as I type this.

We really need some broken units to make progress here.

If you have a broken DX3 Pro and live in US, please contact me and I will purchase it from you.

Doing Jesus`s work. God Bless.

 

[splkn]

I can not find. Can you provide a link to the product?

http://www.carbideprocessors.com/t-handle-hex-driver-2mm-x-200mm-wiha-33436/

 

[amirm]

5/64th also works and since I hate buying one tool at a time, I bought this nice set from Amazon: https://smile.amazon.com/gp/product/B013H2Y0T4/ref=ppx_yo_dt_b_asin_title_o04__o00_s00?ie=UTF8&psc=1