Test WIIM pro+ with different power supplies

Let's not get into theoretical debates. Those who haven't tried listening with a linear power supply shouldn't write their opinions, because it's already known, especially about something like this: "I just listen to music and am happy." Everyone is happy for you, too.

Let's put it this way: I tried it and, 1. I didn't hear anything, 2. I heard this and that.

I'll start with myself. Used power supply.

I didn't particularly expect to hear a difference, but I did. The changes are as follows: the highs became a little clearer and more precise. But the biggest changes occurred in the low frequency range; the bass seemed to "pull itself together" and became more elastic.
 
Maybe next month I'll purchase a LPS. Right now I ordered some cables and adapters so I can readily measure the output from the power supplies I have.

Maybe the LPS has better transient response in relation to power demand? I can't imagine the output stage of the Pro Plus pulling that much power but you never know. Lemme find that other thread where someone replaced the opamps as they detailed the current part number.
 
Here's the PDF for them, not much power draw, so I don't think it's transient response.

Probably the isolation provided by a LPS.
 
Maybe next month I'll purchase a LPS. Right now I ordered some cables and adapters so I can readily measure the output from the power supplies I have.

Maybe the LPS has better transient response in relation to power demand? I can't imagine the output stage of the Pro Plus pulling that much power but you never know. Lemme find that other thread where someone replaced the opamps as they detailed the current part number.

But it's not about power consumption, of course. The idea is to eliminate high-frequency interference that affects the DAC's operation.
 

But it's not about power consumption, of course. The idea is to eliminate high-frequency interference that affects the DAC's operation.
But that's the role of filtering, ferrite.. etc... not new...
;-)
 
But that's the role of filtering, ferrite.. etc... not new...
;-)
Who would argue? The included Pro Plus power supply has especially many filters.. ;)

Have you tried it with LPS yet? There's no high-frequency interference at all, even in the cheapest one.
 
Who would argue? The included Pro Plus power supply has especially many filters.. ;)

Have you tried it with LPS yet? There's no high-frequency interference at all, even in the cheapest one.
You can hear the high frequency interference? Might be something else amiss, but, I'll try with a LPS eventually.
 
You can hear the high frequency interference? Might be something else amiss, but, I'll try with a LPS eventually.
Of course not. :D I meant, LPS doesn't have them at all, and there's no need to filter them. But the impact on WiiM's performance is clearly noticeable.
 
WiiM Pro Plus uses this DAC.

Seems that the analog output stages take in power externally. So, quite possibly noise in the power would make its way in.
 
Nope. I'm actually looking at chip data sheets and seeing where noise could be coming from. Trying to determine if spending even more money on a power supply would actually benefit anything quantitatively.

Possibly a LPS matters, I'll measure it all once I get some adapters in for USB that I can connect to my o-scope and see how much noise there is between the OEM power adapter and the Apple adapter. I don't think I can check the dual USB-C 35 watt one as it requires a data signal to be sent to request what voltage to be sent. But, I can measure the RCA output of the WiiM Pro Plus which is probably the better place to check since that's the final output of the WiiM Pro Plus and if there was any noise, it would most certainly be there.

And, an LPS costs extra. I'm not 100% against it but I'd like to see something on the o-scope.
 
Nope. I'm actually looking at chip data sheets and seeing where noise could be coming from. Trying to determine if spending even more money on a power supply would actually benefit anything quantitatively.

Possibly a LPS matters, I'll measure it all once I get some adapters in for USB that I can connect to my o-scope and see how much noise there is between the OEM power adapter and the Apple adapter. I don't think I can check the dual USB-C 35 watt one as it requires a data signal to be sent to request what voltage to be sent. But, I can measure the RCA output of the WiiM Pro Plus which is probably the better place to check since that's the final output of the WiiM Pro Plus and if there was any noise, it would most certainly be there.

And, an LPS costs extra. I'm not 100% against it but I'd like to see something on the o-scope.
The Pro Plus has been extensively measured here and here.
 

Thread 'My WiiM Pro Plus 2nd sample test' https://forum.wiimhome.com/threads/my-wiim-pro-plus-2nd-sample-test.1580/

The first complete measurements... well before those pointed out...

Better still, early, the first series of tests by onlyoneme is what allowed us to identify problems with the first batch... which justified a hardware revision...

incidentally, it simply demonstrates the limitations of a simplifying protocol, of observations, "sorting by sinad to 1k"... which did not point here to an obvious hardware problem...
"textbook case"
 
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Nope. I'm actually looking at chip data sheets and seeing where noise could be coming from. Trying to determine if spending even more money on a power supply would actually benefit anything quantitatively.
You first have to look at the reference design and/or the way Linkplay/WiiM implemented it, the whole circuit including the dac chip to determine if anything can be engineered better or different. What can be done better according to your findings? Where could noise be coming from?
Possibly a LPS matters, I'll measure it all once I get some adapters in for USB that I can connect to my o-scope and see how much noise there is between the OEM power adapter and the Apple adapter. I don't think I can check the dual USB-C 35 watt one as it requires a data signal to be sent to request what voltage to be sent. But, I can measure the RCA output of the WiiM Pro Plus which is probably the better place to check since that's the final output of the WiiM Pro Plus and if there was any noise, it would most certainly be there.
You are still freestyling and assuming/guessing. (See highlights/bold text)
And, an LPS costs extra. I'm not 100% against it but I'd like to see something on the o-scope.
Do share your measurements, always welcome.
 
WiiM Pro Plus uses this DAC.

Seems that the analog output stages take in power externally. So, quite possibly noise in the power would make its way in.
Really?
The WiiM website says something different:
Diverging from the norm of resampling to set sample rate and bit depth, WiiM Pro stands out by delivering unaltered audio up to 192kHz, 24-bit quality. That's the same as an artist's recording in the studio. The advanced TI PCM5121 DAC produces a remarkable 106 dB SNR and an impressive -92dB THD+N performance.
 
Really?
The WiiM website says something different:
Diverging from the norm of resampling to set sample rate and bit depth, WiiM Pro stands out by delivering unaltered audio up to 192kHz, 24-bit quality. That's the same as an artist's recording in the studio. The advanced TI PCM5121 DAC produces a remarkable 106 dB SNR and an impressive -92dB THD+N performance.

That’s the Pro. Isn’t it the Pro Plus that’s being discussed?
 
Just read the title of the link I posted… 😉
Yes, the title says pro and pro plus, but then the page is only about the pro.
The pro has the TI dac; the pro plus has an AKM dac, and presumably much better analog parts around it unless the TI dac really is why it [the pro] sounds so bad.
But we all know the dac chip itself, or perhaps more accurately, how it's used, it about what, 10% of the overall sound?

Edit: ok, perhaps a slight exaggeration (maybe 20% :)) but the analog components and which dac chip features are actually used are important, and it seems very few companies provide / share that level of technical detail.
 
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