Change power cord to the Ultra

Does anyone know why WiiM Ultra does not have a ground pin in AC power inlet? It is odd for an audio equipment not to have a ground at AC power inlet. For WiiM Pro Plus, I use a Dell laptop charger (GaN SMPS) with ground pin such that the power supply is fully grounded for protection.
My Audiolab 8000A doesn't have a ground connection either. I always thought it was strange.
 
Do double blind ABX tests, get someone to fit and to remove the clamp, not telling you which is which, then note A or B is best.
This is why I like review with both objective and subjective like what Erin and audioholic. The subjective they say has a proof of measurement why it sound like that. Audio quest anyone?
 
Does anyone know why WiiM Ultra does not have a ground pin in AC power inlet? It is odd for an audio equipment not to have a ground at AC power inlet. For WiiM Pro Plus, I use a Dell laptop charger (GaN SMPS) with ground pin such that the power supply is fully grounded for protection.
Its a class II device, dont need any ground at AC power inlet.

Very common in japanese products like Denon, Yamaha , Onkyo and such….
 
Its a class II device, dont need may ground at AC power inlet.

Very common in japanese products like Denon, Yamaha , Onkyo and such….
Provide your critics with measurements along with your subjective and they will believe on you. And from there, you can make them that they don’t know what they’re talking about.
 
Do double blind ABX tests, get someone to fit and to remove the clamp, not telling you which is which, then note A or B is best.
This can probably be done in a near future.
Subjectively, and without any objective proof I will say that the sound got a little cleaner in the higher regions with the two ferrite chokes, like its about 1 dB more treble at 10 KHz. However, Im sure the frequency response looks exactly the same with and without ferrite chokes on the power cord. This listening impression is when using the inbuilt dac and RCA output on the Ultra. The sound also gets slightly leaner in the bass, meant in the best possible way. Small differences, but good enough for me to let the ferrite chokes stay.
 
Last edited:
This can probably be done in a near future.
Subjectively, and without any objective proof I will say that the sound got a little cleaner in the higher regions with the two ferrite chokes, like its about 1 dB more treble at 10 KHz. However, Im sure the frequency response looks exactly the same with and without ferrite chokes on the power cord. This listening impression is when using the inbuilt dac and RCA output on the Ultra. The sound also gets slightly leaner in the bass, meant in the best possible way. Small differences, but good enough for me to let the ferrite chokes stay.

Not interested unless you can prove it. Run REW sweep with and without the RFI block

Use measuring equipment to compare the mains signal with and without the block.
 
Not interested unless you can prove it. Run REW sweep with and without the RFI block

Use measuring equipment to compare the mains signal with and without the block.
Maybe onlyoneme can help with this ?
He did measure that with a lowpass filter used with the Ultra, the measurements and SINAD get better. Now, those ferrite chokes works much higher up in frequency so one has to have measurement gear that can work up to 600 mHz , impossible with REW.

RoB Watts from Chord has proven that RFi is audible when listening to music even if its in the mHz area.
Scroll to 5:00 in the video were he begins to explain in detail how he did:

 
Last edited:
Maybe onlyoneme can help with this ?
He did measure that with a lowpass filter used with the Ultra, the measurements and SINAD get better. Now, those ferrite chokes works much higher up in frequency so one has to have measurement gear that can work up to 600 mHz , impossible with REW.

RoB Watts from Chord has proven that RFi is audible when listening to music even if its in the mHz area.

Proven? Scientific papers, or just techno babble?
 
I think since this is subjective review and would like to share his thought we should just read and appreciate what he provided whether you agree on it or not. As I been saying, topic such objective vs subjective is toxic and can lead to set someone on fire.
 
Its a class II device, dont need any ground at AC power inlet.

Very common in japanese products like Denon, Yamaha , Onkyo and such….
Thanks for the information.

The article says;

A functional ground differs from protective earth ground in that it does not offer shock protection from a hazardous voltage. However, it does help to mitigate electromagnetic noise or EMI. This protection can be of paramount importance in the medical market. A functional ground mitigates EMI Ensuring the devices operate well without interfering with nearby electronic equipment.

Does this mean that a ground pin can help reduce EMI if designed properly?
 
Thanks for the information.

The article says;

A functional ground differs from protective earth ground in that it does not offer shock protection from a hazardous voltage. However, it does help to mitigate electromagnetic noise or EMI. This protection can be of paramount importance in the medical market. A functional ground mitigates EMI Ensuring the devices operate well without interfering with nearby electronic equipment.

Does this mean that a ground pin can help reduce EMI if designed properly?
It might.
A metal cabinet thats earthed is like a well screened RCA cable, - less vunerable to EMI/RFi than a plastic cabinet, or a RCA cable without coaxial copper shield.
 
If phono preamp not used… connect back plate ground point (screw included) to wall outlet ground.
 
It might.
A metal cabinet thats earthed is like a well screened RCA cable, - less vunerable to EMI/RFi than a plastic cabinet, or a RCA cable without coaxial copper shield.
Good point. Perhaps, I should wrap my WiiM Pro Plus with aluminum foil - I use Ethernet connection, no bluetooth, no remote control.
 
Good point. Perhaps, I should wrap my WiiM Pro Plus with aluminum foil - I use Ethernet connection, no bluetooth, no remote control.
Now youre being a hardcase audiophile :giggle:.
One can do it only to see if Rob Watts is right about RFi .

One maybe more practical drill about this is to make two pair of RCA interconnects , one with a good coaxial copper shield and one with just two cables , not twisted . The cable with shield will sound better and darker .
I did this experiment two years ago .
So its definitely better with shield when using analog connection .
 
Now youre being a hardcase audiophile :giggle:.
One can do it only to see if Rob Watts is right about RFi .

One maybe more practical drill about this is to make two pair of RCA interconnects , one with a good coaxial copper shield and one with just two cables , not twisted . The cable with shield will sound better and darker .
I did this experiment two years ago .
So its definitely better with shield when using analog connection .
I abandoned unbalanced cable long time ago. I use balanced cables for analogue signals and stick with equipment with balanced inputs or outputs.
 
I abandoned unbalanced cable long time ago. I use balanced cables for analogue signals and stick with equipment with balanced inputs or outputs.

Most stuff is fake balanced though. Just unbalanced over XLR. Better connector, sure, but still unbalanced.

My pre is fake balanced, but my amps are fully balanced.
 
Back
Top