Chapeau ou non? (PCM5102MK non-HAT DAC review)

[Linards]

Got a very similar high frequency oscillations when measuring a M-track solo in loop. No idea what's causing it. It is very little though.

@MCH , thanks for info!
Yes, oscillation is minute. I don't recall it when I was testing E2X2 in loop... but I will double check next time.

 

[Linards]

(Accurate french translation is '' chapeau ou pas ? " , ''chapeau ou non'' doesn't mean anything btw )

@Karmacoma , Thanks for the note! I hope it does not hurt French speaker eyes too much.
I just knew that I will mess up 3 word sentence somehow!

 

[Sokel]

@Sokel Thanks for this note! I use minimum gain and leave it like that on ADC and on external indicator it does not seem to clip... You got me thinking if I should increase gain on ADC when measuring attenuated signals. Potentially this could give a better resolution, right?

It could but you would need an extra clean pre,experiment though and you'll see.
ADCs usually have a sweet spot around 1-1.5V or around -1db to -3db and you must also take the input independence on account,sometimes is low.
Practice makes perfect

 

[Graham849]

I voted

Chapeau​

for the effort put into the review, and the possibility of improvement. Well done!

 

[jbrown]

Thanks for the effort. I voted "non" but if it had reached 95+ SINAD @ 1.0v or more it would have been "chapeau" for sure.

 

[JakeK]

I tip my hat to you for the interesting and informative review.

I don't have any use for the product itself though.

 

[charlielaub]

The Pi (any model) is a complete mess when it comes to ground and radiated noise. When using a HAT the PCB layout must really be optimized to reject all of that crap. What you have tested is a very cheap design, and the performance is about what I would expect. The same problem can occur with any computer but is especially problematic with the Pi and other SBCs. After struggling with audio quality from earlier versions of the Pi upt to the Pi 4, I now only use USB DACs that have their own power supply and USB isolation and with balanced analog connections that minimize noise pickup.

 

[GWolfman]

This is great work! Keep the RPi hat reviews coming. I’d like to see the winner of this showdown!

 

[Gradius]

Found this one, costs around $20:

https://www.aliexpress.com/item/1005001587136416.html

Besides, is plug&play.

Dual DAC:

https://www.aliexpress.com/item/1005005914022540.html

 

[jasonhanjk]

5.3uV noise, good for hobbyist speaker project.

 

[Milanraf]

With those 2nd harmonic dominance, wide bandwidth and output filter profile, this could well be the el-cheapo tube-sound-lovers panacea for the digital era.
Giù il cappello!

 

[trungdtmc]

I also measured with the smallest PCM5102A board on the market, the input signal is from Amanero directly and the other is amanero via ADAU1401.
In below picture it is THD+N vs Level 1kHz

 

[Linards]

I also measured with the smallest PCM5102A board on the market, the input signal is from Amanero directly and the other is amanero via ADAU1401.
In below picture it is THD+N vs Level 1kHz

@trungdtmc , Sweet!
I also have these both boards (GY-PCM5102 and ADAU1401), just haven't started experimenting with them, yet! ^_^
Nice to see the sweep with Amanero! I will look in to getting USB to I2S converter definitely, it will save a lot of time with these boards.
By looking at result I start to think, if RPI 4B does have an impact on board measurements... do you have one RPI at hand to verify even at single point?

 

[somebodyelse]

I can see a pic of the board, but not the sweep.

 

[Linards]

@MCH
Here are measurements of Topping E2X2 frequency response (@ 192kHz sampling frequency) in loop and figure from Amir's review. DAC gain max, ADC gain min. No oscillations, DACs high frequency roll-off @ 20kHz -0.15 dB or so.

 

[JakeK]

So you can test Audio equipment with a Topping E2X2? What else would I need to test line out and headphone out of a PC or even a small amplifier?

 

[Linards]

OK, Guys! There seems to be an issue with measurements of board itself.
It seems that measurements are valid only for entire system RPI (+Volumio?) and PCM5102MK board... here is why.
After @trungdtmc posted sweeps of GY-PCM5102 I did quick 1kHz sine measurements with the same board myself through RPI.

Results are very similar to those in the review, which leads me to think that PCM5102MK board in review is fine. Perhaps it could preform similarly as in @trungdtmc measurements or so. What I have measured is the result of entire system... :/

More figures in the attachment.

 

[Linards]

So you can test Audio equipment with a Topping E2X2? What else would I need to test line out and headphone out of a PC or even a small amplifier?

@JakeK practically any decent audio interface is capable of testing line out signals of board in this review. Problem will be if your testing device preforms similar or better than interface... I even wouldn't try to "review" SOTA DACs with E2X2. That is why Amir spent a lot of money for APx555.
For amps you will need loads (resistors). I bet there are plenty of schematics out there how to do that. Hope it helps. ^_^

 

[trungdtmc]

OK, Guys! There seems to be an issue with measurements of board itself.
It seems that measurements are valid only for entire system RPI (+Volumio?) and PCM5102MK board... here is why.
After @trungdtmc posted sweeps of GY-PCM5102 I did quick 1kHz sine measurements with the same board myself through RPI.

View attachment 359440

Results are very similar to those in the review, which leads me to think that PCM5102MK board in review is fine. Perhaps it could preform similarly as in @trungdtmc measurements or so. What I have measured is the result of entire system... :/

View attachment 359441

More figures in the attachment.

Your measurement results show a lot of noise, including main noise and its harmonics. While H2 and H3 are not too high

 

[Linards]

Your measurement results show a lot of noise, including main noise and its harmonics. While H2 and H3 are not too high

@trungdtmc can you give a shrot description what was your setup in those sweeps?