S.M.S.L PO100, PO100 PRO & PO100 AK - Measurements (Digital Interfaces & DAC)

[Tangband]

Vintageflanker , a short question. In the cheapest SMSL PO100 I see only one clock crystal on the internal pic. In Douk U2 there is three.
One for 44,1 KHz, 48 KHz and ( I guess ) DSD signals.

Using only one crystal as in SMSL PO100 should be optimised for either 44,1 KHz or 48 KHz , and maybe not both at the same time ? I dont understand, but maybe there is no problem.

I know to little about xmos chips but maybe there can be implemented SRC that dont show any artifacts at all , even if the source material are 48 KHz and the crystal is optimised for 44,1 KHz .

Is there a measurable difference between 44,1 KHz input signal or 48 KHz signal in the SMSL PO100?

I write this because in history, there has been some USB/spdif interfaces that show different results depending on the input sampling frequency .

Edit: I found this :

https://www.xmos.ai/download/lib_src-%5Buserguide%5D(1.0.0rc2).pdf

 

[martijn86]

Nice review and products.

Interesting part on the website is the note about support for TV and Android. The question is now does it support usb from a TV with android based smart TV to create additional digital outputs ? Probably not.

https://www.smsl-audio.com/portal/product/detail/id/788.html

I think that's exactly what you can expect them to do. Android is really just a Unix based operating system. You can use USB Audio devices on Android, just like USB Ethernet adapters, USB Storage etc. Sometimes the smart TV interface doesn't expect completely new ports but they'll be active after a reboot. In theory, you should be able to run a single USB cable to a USB dock with 2.5Gbit Ethernet, card reader inside your media cabinet and connect a USB DAC.

 

[Haskil]

Merci VintageFlanker pour ce travail intéressant qui continue de démystifier les interfaces numériques tout en étant sans complaisance pour la partie DAC...

 

[Stokdoof]

I think that's exactly what you can expect them to do. Android is really just a Unix based operating system. You can use USB Audio devices on Android, just like USB Ethernet adapters, USB Storage etc. Sometimes the smart TV interface doesn't expect completely new ports but they'll be active after a reboot. In theory, you should be able to run a single USB cable to a USB dock with 2.5Gbit Ethernet, card reader inside your media cabinet and connect a USB DAC.

Thanks

 

[Sokel]

Vintageflanker , a short question. In the cheapest SMSL PO100 I see only one clock crystal on the internal pic. In Douk U2 there is three.
One for 44,1 KHz, 48 KHz and ( I guess ) DSD signals.

Using only one crystal as in SMSL PO100 should be optimised for either 44,1 KHz or 48 KHz , and maybe not both at the same time ? I dont understand, and maybe there is no problem.

I know to little about xmos chips but maybe there can be implemented SRC that dont show any artifacts at all , even if the source material are 48 KHz and the crystal optimised for 44,1 KHz .

Is there a measurable difference between 44,1 KHz input signal or 48 KHz signal in the SMSL PO100?

I write this because in history, there has been some USB/spdif interfaces that show different results depending on the input sampling frequency .

Edit: I found this :

https://www.xmos.ai/download/lib_src-%5Buserguide%5D(1.0.0rc2).pdf

Judging from the also cheap Khadas tone1 who can't do 48Khz family DSD while goes to DSD512 with the 44.1 it might be worth testing.

Otherwise as an AKM fanboi I have mixed feelings about SMSL's implementation

Edit:May we please have a1Khz SINAD DSD256 measurement please?
I'm curious about the noise level of such.

 

[BR52]

Thank you for the great review VintageFlanker. I am curious to see your next review, hope you can find the time for it.
A happy NEW YEAR and most important, health.

 

[VintageFlanker]

Confused though, amazon has the pro listed a dac.. it's a ddc, right? Only the AK has a dac.

Yep, only the AK can act as the DAC.
These are, unfortunately, common misconceptions with Amazon product descriptions...

Hope your 2023 audio adventures find a use for that PO100 AK!

Oh, I have better plans for this one: being that flawed, it is going back to Amazon!

The digital tests could be made in a different way, maybe more easy and even more accurate.

Many thanks for the input, Matthias!

Sadly, I don't have any RME nearby anymore... If ever, you would have some surplus ADI-2/4 PRO SE somewhere, I'm sure I could help with that. Just sayin' !

Otherwise as an AKM fanboi I have mixed feelings about SMSL's implementation

One result is insanely good for a product like this (Left SINAD is better than many balanced DACs at whatever price) Looks like they either focused on one digit only, or that my actual unit is simply flawed. Maybe @SMSL-Mandy may comment the results?

Is there a measurable difference between 44,1 KHz input signal or 48 KHz signal in the SMSL PO100?

Yes there will, as there is measurable differences between 44.1 & 48kHz with any DAC anyway. Any particular test you would have in mind?

The question is now does it support usb from a TV with android based smart TV to create additional digital outputs ? Probably not.

My guess is that could be possible with Android TV + such apps as UAPP: https://play.google.com/store/apps/details?id=com.extreamsd.usbaudioplayerpro

 

[mickeyinthehouse]

@VintageFlanker douk audio u2 or po100 is better in ur testing? Planning to get a DDC soon

 

[Cc-Mode]

Thanks for the review and sharing !!

 

[charleski]

The frequency response is way off. We get almost 5.1dB missing amplitude at 20kHz for both channels

This suggests they're using one of the Slow Roll-Off filters in the 4493.

 

[VintageFlanker]

This suggests they're using one of the Slow Roll-Off filters in the 4493.

Correct. It behaves the same as AK4493 Slow filter, that I measured months ago with the ADI-2 DAC FS V2:

@VintageFlanker douk audio u2 or po100 is better in ur testing? Planning to get a DDC soon

I posted U2 Jitter plots earlier. I just relaunched REW FFT and got the exact same SINAD for both:

Won't do any more testing with the Douk, I'm running out of time. The PO100 is a better product anyway. More compact, better built, USB-C and better USB drivers support. Better.

 

[Dennis_FL]

I bought the PO100 last summer. I had the USB from my Mac Mini used exclusively for Roon and I wanted to port another Mac USB out for music from sources other than Roon (like SiriusXM and the Tidal APP) and use one of the other digital inputs on my DAC.

The PO100 worked great and sounded great. But then it died and they had discontinued it on Amazon and although they took the return, I couldn't get another. I tried a much cheaper version by Cubilux and it was horrible....the music was frequently interrupted with noise and static.

So I ended up spending more and got the Allo DigiOne.

 

[PyramidElectric]

Any chance of opening up the PO100 PRO so we can see the crystal implementation? If it is using just one, very interested in seeing how this affects results 44khz vs 48khz.

 

[Firespeed]

I am asking myself, as I already hear some questioning the relevance of the review... "Digital is digital", as such, all S/PDIF interfaces should give you the exact same performance. Well, yes, you are right: they should. Yet, I have already observed measured variations between other similar products, mostly audibly insignificant, but sometimes very noticeable (Frequency response and Jitter among others).

Hello Vintage Flanker and hello to all,

First of all, thank you for this very interesting and exhaustive test!

In a much less professional and technical way than you, and as a "simple" end user, I noticed a big difference between 2 digital connections that should have given the same signal qualities. I'm talking about my recent experience with the Node2i streamer which is not as good as it should be on its digital interfaces (link). Sold 4 to 5 times the price of these SMSL interfaces, it is not acceptable.

Hence the importance of these reviews and, here, your work even on coax and optical connections!

So thank you! It is very relevant !!!

 

[Tangband]

Any chance of opening up the PO100 PRO so we can see the crystal implementation? If it is using just one, very interested in seeing how this affects results 44khz vs 48khz.

Maybe Vintageflanker can do a measurements with 1 kHz sinetone at the spdif coaxial output , first with 44,1 KHz digital input signal and then with 48 kHz input ?

Im already happy that Vintageflanker has done extensive testing for us , so maybe If he got the time …?

As linked above to the xmos SRC implementation, it seems there is a possibility to do really good conversion from 44,1 to 48 KHz or reverse.

Expensive DDC converters , such as Matrix xspdif 2 uses two crystal clocks , one for 44,1 and one for 48 kHz, a FPGA and a xmos chip. Does it matter at all ?

Vintagerflanker, as firespeed already has said, your work is really important and the reason for that is that using a laptop with those cheap DDC:s might be a much better bargain than buying a streamer for 500 dollars. There is also no customer help from the hifimagazines to get, because SMSL dont do much advertising and are therefore never tested.

 

[JasonC331]

I bought the PO100 last summer. I had the USB from my Mac Mini used exclusively for Roon and I wanted to port another Mac USB out for music from sources other than Roon (like SiriusXM and the Tidal APP) and use one of the other digital inputs on my DAC.

The PO100 worked great and sounded great. But then it died and they had discontinued it on Amazon and although they took the return, I couldn't get another. I tried a much cheaper version by Cubilux and it was horrible....the music was frequently interrupted with noise and static.

So I ended up spending more and got the Allo DigiOne.

Same here worked fine then one day just died! Now I have the P01000 Pro, I'm still going to get them to replace the other. Just on the principle of not last a year.

 

[Tangband]

Yep, only the AK can act as the DAC.
These are, unfortunately, common misconceptions with Amazon product descriptions...


Oh, I have better plans for this one: being that flawed, it is going back to Amazon!


Many thanks for the input, Matthias!

Sadly, I don't have any RME nearby anymore... If ever, you would have some surplus ADI-2/4 PRO SE somewhere, I'm sure I could help with that. Just sayin' !


One result is insanely good for a product like this (Left SINAD is better than many balanced DACs at whatever price) Looks like they either focused on one digit only, or that my actual unit is simply flawed. Maybe @SMSL-Mandy may comment the results?


Yes there will, as there is measurable differences between 44.1 & 48kHz with any DAC anyway. Any particular test you would have in mind?


My guess is that could be possible with Android TV + such apps as UAPP: https://play.google.com/store/apps/details?id=com.extreamsd.usbaudioplayerpro

I have now read more carefully how you have done the testing and many measurements seems to be with 44,1 kHz 24 bit. Thats fine and good for most music listening, but it looks like you did the jitter testing at 48 kHz.
Is the jitter test result the same for 44,1 kHz ?
(Maybe I ask to many silly questions, but Im genuinely interested.)

 

[Multicore]

Conclusion: good for mono!

Btw, nice work with the measurements.

 

[Dennis_FL]

Same here worked fine then one day just died! Now I have the P01000 Pro, I'm still going to get them to replace the other. Just on the principle of not last a year.

They did it for me.....but kept 15% restocking fee and said I could get that back if I reapplied for the refund.....I asked them why they would restock a dead unit.

 

[AdamG]

Merci VintageFlanker pour ce travail intéressant qui continue de démystifier les interfaces numériques tout en étant sans complaisance pour la partie DAC...

Please post In English in the future. Thanks

Translated:

“Thank you VintageFlanker for this interesting work which continues to demystify digital interfaces while being uncompromising for the DAC part...”