Review and Measurements of SMSL X-USB Digital Audio Converter

[Jimster480]

You mean for D50? If so, no. It has a nice auto-on, auto-off display so once the music starts playing it shuts off and the noise goes away.

Alright, i was wondering if the other jitter you recorded had to do with the screen aswell.

 

[trl]

It is probably off-topic and very controversial topic, but in my measurements USB's +5V ripple & noise had a little bit of influence in DAC's output jack plug, not within the audible range, but more between 3-8MHz. This most likely has no influence on the jitter (haven't tested this, have no decent ADC around). My ears were unable to discern between a noisy USB port and a silent one, just my scope was able to see different results.

One thing's for sure: I always measure the +5V USB's noise before plugging my DAC! If less than 1mV then I'm OK with it, otherwise...I just swap the USB port or the computer. Also, I never use the front USB ports from my desktop nor the USB ports from laptop's docking station!


Front_USB_port, Rear_USB_port, HP8460p_left ,HP8460p_right


iMac_27"_2013, Lenovo_T430_dock, Lenovo_T440_dock

BTW, I have a Lenovo charger with built-in USB hub that measures only few hundreds of uV of AC ripple & noise, almost flat line, so probably the noise I see on my scope it's induced by computer's inside components and not from a bad power regulator. Also, the same noise is still there is laptop's powered from battery, so no difference between AC mains and internal battery.

It would be nice if Amir could compare the jitter and perhaps the noise of a USB-powered DAC on 2 USB ports: one with a very noisy +5V vs. anther USB port with a very clean +5V. In case you already did that, sorry for not being able to find it out.

Thank you very much!

 

[amirm]

Thanks trl. I should make a project out of characterizing USB power....

 

[bbfoto]

Thanks trl. I should make a project out of characterizing USB power....

Thank you for this test, Amir. Obvious n00b here reviving and old, dead thread to ask a question! ...

Are there any newer similar devices that perform significantly or even moderately better than this SMSL?


I am currently using the device under review here in my "audiophile" (*cough*) car audio system. I am generally pleased with the results and there are no particular issues or problems in use. But as with most members here, I'm always seeking the best possible performance.

I use a standalone 20,000mAh rechargable "USB battery bank" to supply power to the SMSL via its DC power input connector, and to supply a powered USB hub to keep the Tablet charged via its USB connection.

Will using the USB Hub "re-clock" or "re-sample" the digital output from the Android Tablet before sending it on to the SMSL X-USB???


GOAL: Extract the best possible "bit-perfect" and "clean" digital audio output signal from an Android Smartphone or Tablet that is used as the music storage and playback Source.

The following is my signal chain (when not using the powered USB Hub):

SOURCE: An 8" or 12.4" Samsung Galaxy Tab S2/Tab S7+ Andriod Tablet with local lossless music files stored on an internal microSDXC memory card, and using the USB Audio Player Pro music player app for Android.

CONNECTIONS:

a. USB out from either of the Galaxy Tablets using an OTG USB Cable connected to the USB input on the SMSL X-USB.

b. Either digital Toslink optical or digital Coaxial output cable from the SMSL X-USB to the corresponding inputs on a miniDSP C-DSP 8x12 v2 DIRAC Live processor.

c. Analog RCA preamp outputs from the miniDSP 8x12 processor to various 12vdc car audio amplifiers powering a 3-way front speaker system comprised of the Purifi PTT6.5 as midbass, Dynaudio Esotar² 430 midrange, and BlieSMa T25B-6 beryllium tweeter, and an older Infinity Beta-X 15" subwoofer in a custom sealed enclosure.

I enjoy listening to my car audio system while driving, of course, but also when not driving, during my daily lunch hour and breaks at work. (I've installed an additional relay-isolated 12V deep cycle marine battery for these longer "car off" listening sessions without the car running that would otherwise provide power & charging for the audio system).

I saw the mention of the Schiit Eitr, and will check it out, but was interested in something perhaps more current to replace the SMSL X-USB. Would the Topping D10S qualify and work as a suitable replacement in this use case scenario?

TIA!

 

[Katji]

? So was this before the pink panthers came?

 

[staticV3]

Are there any newer similar devices that perform significantly or even moderately better than this SMSL

There's the recently released SMSL PO100.
No measurements yet unfortunately, but should perform just fine

I am currently using the device under review here in my "audiophile" (*cough*) car audio system. I am generally pleased with the results and there are no particular issues or problems in use. But as with most members here, I'm always seeking the best possible performance

As most people here will tell you, the real gains come from better speakers/DSP/acoustic treatment. Digital Audio is a solved problem.

Will using the USB Hub "re-clock"

Modern USB Audio and DACs are asynchronous meaning the clock is inside the DAC (or DDC) itself. Adding a hub does not affect that.

or "re-sample"

It's a hub, not a DDC. It's not capable of resampling.