WiiM pro soundquality as a digital transport and the digital volume control quality when listening to music

[Tangband]

I take it all of these comparisons and therefore your conclusions were performed using sighted testing?
Keith

Yes.
I listened to one song at a time, while comparing the two streamers side by side during three days, and the power supplies for the WiiM pro were used longtherm a couple of days each, before I made the listening test against the Linn Klimax DS/0. So very subjective review and I have no measurements to back this up at all.

Subjective thoughts again: The klimax DS/0 sound a tiny, tiny bit cleaner than WiiM pro with stock power supply and connected to the Rega Dac R . This differences dissapears completely if I use the Apple iPad charger A1357 from 2012.

Someone should measure the stock power supply for the WiiM pro to se how much noise it puts out on the main grid ( If any ).

Vintageflanker or onlyoneme ?

 

[Purité Audio]

Without wishing to diminish your efforts sighted comparisons in this particular scenario are more or less completely worthless.
It’s just anecdote ,.
I have just seen a pig fly past the window.
Keith

 

[onlyoneme]

Someone should measure the stock power supply for the WiiM pro to se how much noise it puts out on the main grid ( If any ).

I do not have an equipment for this.
In terms of the ripple noise generated on the DC side - it's really noisy.

 

[morillon]

I do not have an equipment for this.
In terms of the ripple noise generated on the DC side - it's really noisy.

the behavior in dc, noise, etc etc also questionable on the coaxial spdif output as you observed..

 

[BDWoody]

Yes.
I listened to one song at a time, while comparing the two streamers side by side during three days, and the power supplies for the WiiM pro were used longtherm a couple of days each, before I made the listening test against the Linn Klimax DS/0. So very subjective review and I have no measurements to back this up at all.

Instead of measurements, how about a controlled test? We've been down this road over and over. You tend to just believe your impressions without even considering that this whole focus on controlled testing you find around here has any merit.

 

[Tangband]

I do not have an equipment for this.
In terms of the ripple noise generated on the DC side - it's really noisy.

Ok - thanks for knowing this.

 

[Tangband]

the behavior in dc, noise, etc etc also questionable on the coaxial spdif output as you observed..

What If the power supply is leaking noise on the grid where other electronics are connected, such as power amp and dac ?

 

[Tangband]

I do not have an equipment for this.
In terms of the ripple noise generated on the DC side - it's really noisy.

I found measurements for my used Apple iPad charger, Apple 10W 2.1 A USB Power Adapter A1357 from 2012 :



”The iPad charger almost eliminates the ripple; only a small blip is visible in the orange spectrum on the right. The noise level is low, although appreciably worse than the iPhone ( charger ) ”

A dozen USB chargers in the lab: Apple is very good, but not quite the best

When you buy a USB charger, how do you know if you're getting a safe, high-quality charger for your money? You can't tell from the outside...

www.righto.com

 

[morillon]

I found measurements for my used Apple iPad charger, Apple 10W USB Power Adapter A1357 from 2012 :

View attachment 330864View attachment 330865

”The iPad charger almost eliminates the ripple; only a small blip is visible in the orange spectrum on the right. The noise level is low, although appreciably worse than the iPhone ( charger ) ”

A dozen USB chargers in the lab: Apple is very good, but not quite the best

When you buy a USB charger, how do you know if you're getting a safe, high-quality charger for your money? You can't tell from the outside...

www.righto.com

the old little apple was also surprisingly clean...but with its 1A it would probably be too tight for the consumption of a "plus" pro
for rappel..interresting

Index of tested and reviewed USB power supplies/chargers

 

[BenjaminB]

I have just seen a pig fly past the window.

Hm, does this happen often to you?

/worried

 

[Purité Audio]

It is like a subjective review I am absolutely certain I saw it, unfortunately I have no actual proof.
Keith

 

[onlyoneme]

I found measurements for my used Apple iPad charger, Apple 10W USB Power Adapter A1357 from 2012 :

View attachment 330864View attachment 330865

”The iPad charger almost eliminates the ripple; only a small blip is visible in the orange spectrum on the right. The noise level is low, although appreciably worse than the iPhone ( charger ) ”

A dozen USB chargers in the lab: Apple is very good, but not quite the best

When you buy a USB charger, how do you know if you're getting a safe, high-quality charger for your money? You can't tell from the outside...

www.righto.com

WiiM Pro Plus stock charger, 20 MHz BW, 0.350 A load:

 

[Tangband]

WiiM Pro Plus stock charger, 20 MHz BW, 0.350 A load:

View attachment 330889

View attachment 330890

View attachment 330880

View attachment 330887

Thank you onlyoneme.
That looks terrible ! Edit : fooled by the graph

 

[onlyoneme]

Thanks.
That looks terrible !

I wouldn't say that. For me it looks similar to other ordinary SMPS chargers.

 

[MAB]

Thanks.
That looks terrible !

Really?
How does it sound, unsighted?

p.s. It looks like a power supply, not good or bad. And your AC mains look bad too, really horrible, if you actually looked. You jump to conclusions, and you don't seem to have a good understanding of what is good or bad and what matters here, or how to actually measure.

You could avoid this if you started with a meaningful unsighted listening test, rather than allow all of your bias to interfere. You could actually accomplish that with your skills, but diagnosing power supply impacts on sound quality is well beyond your and most other people's technical capabilities. Instead you let bias seep into every aspect, even your incorrect judgement of the power supply fundamentals.

 

[Tangband]

I wouldn't say that. For me it looks similar to other ordinary SMPS chargers.

Ok, maybe the graph is fooling me. Do you mean that most ordinary SMPS chargers are rather bad in the noise department ? Or good enough ?

 

[onlyoneme]

Ok, maybe the graph is fooling me. Do you mean that most ordinary SMPS chargers are rather bad in the noise department ? Or good enough ?

What being "bad" or "good enough" means exactly? I've seen chargers with RMS ripples above 100 mV and PtP above 500 mV. Such ones I would call "bad" I guess.
There are ultra low noise SMPSes on the market, but it requires a lot of efforts to reach such a level and it's not really important in many cases.

 

[onlyoneme]

Ok, maybe the graph is fooling me. Do you mean that most ordinary SMPS chargers are rather bad in the noise department ? Or good enough ?

This is for Apple one, does it look better?

 

[Tangband]

This is for Apple one, does it look better?

View attachment 330907
View attachment 330908
View attachment 330909
View attachment 330910

Ouch - which model type is this ( can be seen on the device )
Is it a real Apple charger or a copy ?
A fake Apple charger can have 50 times higher noise.

This is the one Apple 10W 2.1 A Power Adapter A1357 I use with the WiiM pro:

And a fake iPad charger :

A dozen USB chargers in the lab: Apple is very good, but not quite the best

When you buy a USB charger, how do you know if you're getting a safe, high-quality charger for your money? You can't tell from the outside...

www.righto.com

————————
Ok, maybe extreem examples above.


Onlyoneme: If we look at the numbers ( and ignore the different scales of the graphs ) of the measurements you have made on the WiiM pro charger and the measurements for my non fake apple iPad A1357 charger, we can see that the noise is:

WiiM pro stock power supply: 13.03 mV rms, 177,5 mV pk-pk
Apple ipad A1357 2.1 A. : 6.46 mV rms , 72 mV pk-pk

Thank you for measuring the noise from the stock power supply for the WiiM pro .

 

[onlyoneme]

Ouch - which model type is this ( can be seen on the device )
Is it a real Apple charger or a copy ?
A fake Apple charger can have 50 times higher noise.

This is the one Apple 10W 2.1 A Power Adapter A1357 I use with the WiiM pro:

View attachment 330911

And a fake iPad charger :

A dozen USB chargers in the lab: Apple is very good, but not quite the best

When you buy a USB charger, how do you know if you're getting a safe, high-quality charger for your money? You can't tell from the outside...

www.righto.com

View attachment 330914
————————

Onlyoneme: If we look at the measurements you have made on the WiiM pro charger and the measurements for my non fake apple iPad A1357 charger we can see that the noise is:

WiiM pro stock power supply: 13.03 mV rms, 177,5 mV pk-pk
Apple ipad A1357 2.1 A. : 6.46 mV rms , 72 mV pk-pk

Thank you for measuring the noise from the stock power supply for the WiiM pro !

A2118, rather genuine. Results would be slightly better with better approach as this charger has bit too high common mode voltage.
Do not compare any results if you don't know how particular measurements were made.

Due to this note
"In the power quality section, the high-frequency (left) images show 40 milliseconds of the waveform in yellow, and the frequency spectrum up to 234 kHz in orange. The low-frequency (right) images show 1 second of the output voltage in yellow and the frequency spectrum up to 600 Hz in orange. Because the frequency spectrum is measured in dBm, it is logarithmic; every division higher indicates 20 dB which is 10 times the voltage and 100 times the power."
is barely comparable at best.