Loxjie D40 Pro DAC & HP Amp Review

[robladw]

Alright I must say after a couple of days with it I am impressed. One it has a much better headphone amplifier than my Marantz HD-Dac1. It is a much better DAC than my HD-DAC1. I can hear clear differences between them. I do not think this has anything to with effort though. I think this is all about D40 Pro just being cleaner with a lower noise floor and not trying to provide any color. I have to agree with @amirm I am not sure how anyone can misconstrue this as clinical. All it does is its job of converting digital to analog with as little noise and distortion as possible while not trying to provide color. Thank you for the review and recommendation as I was looking at a couple of more expensive and similar DACs when I ran across this review and decided to go with it. You saved me a couple of hundred dollars off the other DACs I was looking at. This more than met my needs and what I was doing with the Marantz while giving me additional functionality with Bluetooth and a upgrade to my headphone amp. That is hard to beat.

 

[fffffgggg54]

I ordered a unit based on this review and the similarity in design and build to another DAC I own, the Anedio D2 (similar design philosophy as Topping/SMSL/Loxjie/Gustard and similar made-in-china high SINAD DACs but US-based company and released ~10 years earlier).

Subjectively, I can't tell the difference between the two. I hear no issues with the unit, so I will say it is transparent.

The physical features of the unit are nice, many settings are accessible. The display and LEDs are bright and easily readable. Volume control via the encoder is responsive without any skipping if you go too fast, as was the case with my Anedio unit. The clicks on the encoder feel good, though there is some play. Build quality is mediocre, as Amir noted. The aluminum case, while not flimsy, doesn't instill any sort of confidence. There is some rattling when I put the unit down from the case. The unit gets quite warm to the touch when left powered on.

Spoiler: Teardown

I was curious to see what was inside, so I took the cover off. Here are some photos taken with my phone camera and a flashlight.
Inside:

Dac chip:

Output stage? Not sure what chips these are.

AES and I2S input, 75176B=differential bus transceiver, no clue beyond that

BT chipset

Microcontroller (Generic version of STM32F103VET6?) and clocks

Headphone amp:

USB:

Power supply (case tied to ground)

 

[Mark K]

Having been using it for weeks and I cannot be happier. The headphone output is very powerful.

 

[KMS Bisko]

SMSL(big sis company of loxjie) just release there DO400 for 499$, which looks like the same thing as d40 pro, but have 2 more opamp 1612 for IV stage(9 to 11), different and heavier case, better screen, preamp mode and sound color function, other wise they are the same. My d40 pro is going to arrive, but IDK should I sell it and get the DO400 for ~100$ more.

 

[T&T]

Wonder between this loxjie and the cheap SMSL SU 1, which sound better.

 

[wsadkmt]

D40 Pro firmware update
2023-08-29

LOXJIE AUDIO Official-LOXJIE音频官网

DAC,AMP,Headphone AMP,

www.loxjie-audio.com

 

[Berwhale]

Wonder between this loxjie and the cheap SMSL SU 1, which sound better.

When both are used simply as DACs, there should be no audible differences as they both surpass the audibility thresholds described here: https://www.audiosciencereview.com/...-thresholds-of-amp-and-dac-measurements.5734/

Of course, the Loxjie is also a powerful balanced headphone amplifier and has balanced line outputs (very helpful for avoiding ground loops, especially when the device is connected to a PC), so you would expect is to cost a fair bit more.

 

[peterwen]

http://loxjie-audio.com/download.asp There is a new firmware update for the D40 pro, users can download it here to update it

 

[ivanyi]

http://loxjie-audio.com/download.asp There is a new firmware update for the D40 pro, users can download it here to update it

May I ask what updates are available for this firmware?

 

[ejr]

Has anyone successfully upgraded this firmware?

I found the badly-translated instructions confusing.

Especially this

"Steps：
1）Don't supply power to D40pro first ... "

and this

"6 ) Connect the D40pro service interface to the computer via micro USB cable(NOT the USB
input interface). Press and hold the knob, then turn on the power, and release the knob after 5
seconds. If you see the D40pro starts normally, you need to repeat this operation (when entering the
upgrade mode, D40PRO screen will not light up). ... "

There is only one USB port on my unit (and it is currently connected to a PC). The power cable is plugged into a power strip, which is plugged into a wall socket. What do I do? Unplug it from the wall, then run the upate and plug it back in? (My best guess).

Thanks.

 

[ivanyi]

Has anyone successfully upgraded this firmware?

I found the badly-translated instructions confusing.

Especially this

"Steps：
1）Don't supply power to D40pro first ... "

and this

"6 ) Connect the D40pro service interface to the computer via micro USB cable(NOT the USB
input interface). Press and hold the knob, then turn on the power, and release the knob after 5
seconds. If you see the D40pro starts normally, you need to repeat this operation (when entering the
upgrade mode, D40PRO screen will not light up). ... "

There is only one USB port on my unit (and it is currently connected to a PC). The power cable is plugged into a power strip, which is plugged into a wall socket. What do I do? Unplug it from the wall, then run the upate and plug it back in? (My best guess).

Thanks.

i have already update the fireware,don't mind the description,plugged the usb port is ok.first power off,then Press and hold the knob, then turn on the power, and release the knob after 5 seconds. D40PRO will start and screen will not light up,You can continue following the documentation

 

[Appellate Lawyer]

I emailed both Loxjie (which didn't bother responding) and HiFi Express (which did respond). HiFi Express told me to ignore the instruction, on the YouTube video, to use the service interface (and not the USB connection). (There is no service interface on the D40 Pro.) So I followed the instructions to a T. Nothing happened. I would just wait a couple months for Loxjie or whoever handles their firmware update instructions to issue some proper instructions, lest you wind up bricking the unit because of poor instructions.

 

[ejr]

Sorry to say that I was never able to update mine. I followed ivanyi's instructions to the letter, but no luck. It always fails at the point where the installer is supposed to connect to the device. When I press the connect button (or select "Connect" from the menu) nothing happens. If I press the Start Program button, I just get a message saying "Disconnected". I'm giving up on this until the commany gets its act together. And I'm changing my rating of this product from 3 to 2, for its poor documentation and update and its virtually non-existant tech support (I have literally never received a response to any question regarding the D40 or the D30).

 

[ivanyi]

Sorry to say that I was never able to update mine. I followed ivanyi's instructions to the letter, but no luck. It always fails at the point where the installer is supposed to connect to the device. When I press the connect button (or select "Connect" from the menu) nothing happens. If I press the Start Program button, I just get a message saying "Disconnected". I'm giving up on this until the commany gets its act together. And I'm changing my rating of this product from 3 to 2, for its poor documentation and update and its virtually non-existant tech support (I have literally never received a response to any question regarding the D40 or the D30).

 

[ivanyi]

my computer os is windows 10,when i connect the dac with computer usb 3.0 port is unsuccess,but i change to usb 2.0 port, then succes, so you can consider change usb port or change the computer and try again .this dac is really a good product,but the support is really weak

 

[ejr]

Switching to the USB 2 port did not resolve the problem. Worse, attempting to do so has totally screwed up this device. I now can only output through the headphones. The only other output option is labled "L in" (whatever that means) and I can't find anything in the manual that indicates how to changed this. I have a very expensive balanced powered speaker system connected to the XLRs and now there is no way to enable them. - UPDATE: Okay, I figured this last part out. If I press and hold the output button repeatedly, it will cycle through output choices, one at a time (press for each attempt). - Really poor UI and very bad documentation.

 

[ejr]

Tried again. Since my computer is under my desk and my D-40 is on top of a cabinet, under a TV, I had to run a USB extension cable to reach it. Since the extension cable is USB 3.0, I purchased a USB 2.0 extension cable and tried that as well. No luck. Same result as always. It was never able to connect.

I have to say that I'm not convinced that using a USB 3.0 port or cable would make a difference, since they are supposed to be backwardly compatible to the older standards. And though I would expect there could be an issue if I was trying to use a USB 2.0 cable or device on one that required USB 3.0, I have never seen a case where the reverse was true.

I think this is just shoddy tech support, upgrade, and documentation from Loxjie and I will have to take that into account before I purchase any of their other products.

 

[Berwhale]

Tried again. Since my computer is under my desk and my D-40 is on top of a cabinet, under a TV, I had to run a USB extension cable to reach it. Since the extension cable is USB 3.0, I purchased a USB 2.0 extension cable and tried that as well. No luck. Same result as always. It was never able to connect.

I have to say that I'm not convinced that using a USB 3.0 port or cable would make a difference, since they are supposed to be backwardly compatible to the older standards. And though I would expect there could be an issue if I was trying to use a USB 2.0 cable or device on one that required USB 3.0, I have never seen a case where the reverse was true.

I think this is just shoddy tech support, upgrade, and documentation from Loxjie and I will have to take that into account before I purchase any of their other products.

I would not recommend using a long USB extension cable for a firmware update. You want the connection to be as reliable as possible, which usually means as short as possible.

In my experience, USB 2.0 devices can often have problems when plugged into USB 3.0 (or 3.1 or 3.2) ports regardless of any claims of backwards compatibility (the situation with the different USB standard, their cabling and connectors is frankly a mess). The advice to plug the unit into a USB 2.0 port (the black ones on most motherboards) is sound.

However, none of the above excuses Loxjie from providing proper (or properly translated) upgrade instructions.

 

[ejr]

Thanks for the info. I have to say that my own experience differs from yours (that's not to say it is exhaustive or definitive). But I have used all versions of USB since they were invented and I have encountered any of the issues you mentioned. The only problem I've ever seen is if I mistakenly connected a device that required USB 3.0 using USB 2.0. I did try a single cable from a USB 2.0 port on the front panel of my computer, with no luck. And none of these are what I would consider a long run. None of these are longer than four feet.

I also note that the update app says "Disconnect" (sic) in the lower left corner, in red, right from the outset and that never changes. Furthermore, the Exit menu command doesn't work. I have to click the X on the upper right of the UI to close it. So, I have to wonder if this whole problem is a software issue.

 

[ivanyi]

Thanks for the info. I have to say that my own experience differs from yours (that's not to say it is exhaustive or definitive). But I have used all versions of USB since they were invented and I have encountered any of the issues you mentioned. The only problem I've ever seen is if I mistakenly connected a device that required USB 3.0 using USB 2.0. I did try a single cable from a USB 2.0 port on the front panel of my computer, with no luck. And none of these are what I would consider a long run. None of these are longer than four feet.

I also note that the update app says "Disconnect" (sic) in the lower left corner, in red, right from the outset and that never changes. Furthermore, the Exit menu command doesn't work. I have to click the X on the upper right of the UI to close it. So, I have to wonder if this whole problem is a software issue.

this my upgrade step,hope will helpful

how to upgrade D40 Pro fireware

1.first down the fireware from this url http://loxjie-audio.com/download.asp and save the file on you computer or notebook 2.unzip the file 3.enter the ISP_PC_EN2 folder,and open the ispV2.4.exe 4.on the “File” menu,click the “Open” item 4.load the fireware file,the file is in the upper d...

docs.google.com