Review and Measurements of Topping DX3Pro DAC and Headphone Amp

[noel_fs]

When volume showing it is in DAC pre-amp mode (you can control the volume of the line level outputs, the RCA phono outputs at the rear), when sample rate showing in DAC mode it is at fixed level line output (0dB full line level output).

Thats kinda what I thought, thanks! No idea about the headphone blinking mode?

 

[lucadoc]

The name is DX3 Pro.
Please be sure to install the BT antenna.

Thanks Toku but this device does not appear when I search available devices.

The antenna is installed

 

[noel_fs]

Thanks Toku but this device does not appear when I search available devices.

The antenna is installed

Another dumb question, are you on BT mode?

 

[lucadoc]

Yes, BT source, I tried with two phones

 

[bleachershane]

I was looking at the PCB and noticed it's labeled DX3/DX3pro, implying they planned a non-pro variant based on the same board.

View attachment 17809

What might the difference be in a non-pro version?

Have you got any other photos of the PCB?

 

[bleachershane]

Thats kinda what I thought, thanks! No idea about the headphone blinking mode?

There were other previous mentions of the flashing/blinking headphone symbol, mine did that at first and now doesn't. I can't remember if a conclusion as to what causes it was got to earlier in this thread...

 

[MacDac]

If the idea has arisen that the device fails due to overheating, can anyone disassemble it and check the heating of the chips, perhaps with a thermocouple or just with your hand. If so, then we can stick radiators on the chips and solve possible problems in the future.

If overheating is substantial sticking heatsinks on chips won't help much to effectively dissipate heat due to their modest dimensions, I'm affraid.

 

[Toku]

Yes, BT source, I tried with two phones

Even if BT is not selected for input to DX3 Pro, BT is in the active state even in standby mode, and pairing is possible.

I am using two DX3 Pro, and I can connect two smartphones and iPad Pro2.

 

[777]

If overheating is substantial sticking heatsinks on chips won't help much to effectively dissipate heat due to their modest dimensions, I'm affraid.

No. Thermall resistance between jonction and ambient it is 180 degrees/watt. Between jonction and case 55 degrees/watt. See datasheet OPA2140. If you will use a heathink , the op-amp will be termally safe.

 

[lucadoc]

Even if BT is not selected for input to DX3 Pro, BT is in the active state even in standby mode, and pairing is possible.

I am using two DX3 Pro, and I can connect two smartphones and iPad Pro2.

So my unit is defective or the Bluetooth is not activated... But there is no way to activate /deactivate, am I wrong?

 

[bleachershane]

So my unit is defective or the Bluetooth is not activated... But there is no way to activate /deactivate, am I wrong?

First thing is try a full factory reset, instructions posted earlier in this thread. Second would be to try reflashing the firmware.
After doing these I would then consider the Bluetooth unit to be faulty and you may have to consider sending back to the retailer you purchased from.

 

[MacDac]

No. Thermall resistance between jonction and ambient it is 180 degrees/watt. Between jonction and case 55 degrees/watt. See datasheet OPA2140. If you will use a heathink , the op-amp will be termally safe.

I heave serious doubts about it, as my attempts to cool down my tiny AKM4490 DAC with heatsinks proved otherwise If ambient temperature rises above 30 C (which was the case last summer) passive heatsink cooling simply won't do, especially if the chassis is small and is missing ventholes.

 

[Yuno]

There were other previous mentions of the flashing/blinking headphone symbol

Flashing headphone symbol indicates that dx3 is running in headphone+line out volume controlled mode (meaning audio is output to both at the same time). It's activated with round unlabeled button between + and -

 

[lucadoc]

First thing is try a full factory reset, instructions posted earlier in this thread. Second would be to try reflashing the firmware.
After doing these I would then consider the Bluetooth unit to be faulty and you may have to consider sending back to the retailer you purchased from.

Reset done, no changes... But not important for me, I don't need Bluetooth, it was just to try it

 

[SemperUnum]

Do you guys think it is better to run DX3pro in WASAPI push? I have been using WASAPI event to this point, but after reading your post I switched to 'push'. I thought it is generally recommended to use 'event' with devices that support it. I tried using SACD files, but I can get it to work only if SACD in Foobar is set to PCM. My SACD is set to (double precision with 30kHz filter. DSD direct mode doesn't work, any suggestions?

Today I reset my computer and afterwards both WASAPI (push) and WASAPI (event) work like they should with PCM and DSD. It seems a clean reset might improve things after installing the Topping drivers.

Here are my Foobar2000 settings:

Choosing the correct "DSD : ..." device here is important to get DSD working correctly.

 

[bleachershane]

Flashing headphone symbol indicates that dx3 is running in headphone+line out volume controlled mode (meaning audio is output to both at the same time). It's activated with round unlabeled button between + and -

Brilliant, thanks for clarifying that! So if you're only using the headphone output you really want no flashing/blinking with the headphone symbol.

If you want to listen through headphones while simultaneously having a volume controlled line-level output to say monitors, then the flashing/blinking headphone symbol is what you want.

 

[bleachershane]

Reset done, no changes... But not important for me, I don't need Bluetooth, it was just to try it

Have you tried reflashing the 1.04 firmware onto the unit? It may fix something that was corrupted on the initial install.

The Bluetooth input is surprisingly good and it's a shame if you can't get it working on your unit. I would most certainly contact your retailer for at least a partial refund if one feature of your unit isn't working.

 

[bleachershane]

Here is what I see on my Bluetooth screen on a Huawei P10 (Android 8). When I first installed the DX3 Pro it didn't show up on my list of Bluetooth devices until I hit Scan.

 

[bleachershane]

Today I reset my computer and afterwards both WASAPI (push) and WASAPI (event) work like they should with PCM and DSD. It seems a clean reset might improve things after installing the Topping drivers.

Here are my Foobar2000 settings:
View attachment 19963

View attachment 19964
Choosing the correct "DSD : ..." device here is important to get DSD working correctly.

Found this myself, I was selecting the non-DSD WASAPI modes initially, either missing the options, or they suddenly appeared after fiddling with something. Either way, I've had no issues with DSD playback since then.

 

[lucadoc]

Have you tried reflashing the 1.04 firmware onto the unit? It may fix something that was corrupted on the initial install.

The Bluetooth input is surprisingly good and it's a shame if you can't get it working on your unit. I would most certainly contact your retailer for at least a partial refund if one feature of your unit isn't working.

I did again the firmware upgrade and scanned the Bluetooth devices without any chance . I'll contact Audiophonics