Wiim Amp Ultra new subwoofer sync

[slartibartfast]

Update:
So, I submitted a ticket and got back a response from Wiim. According them the culprit is my phone microphone which is not accurate in the lower frequencies. I also shared with them the new measurements results with the mic and waiting for response.
I suspected that also, so I ordered a Dayton Audio iMM-6C microphone and I redone the measurements.

With the mic the sound is totally different what I used to in the lower frequencies. It's less boomy more accurate, put together. Kinda miss more bass sometimes.
The sub speaker sync is went from subwoofer delay to speaker delay. It now consistently measures between 8ms - 10ms delay to the speakers not like before. Also I did measurements with phase 0 and 180 and it was in both cases 8ms to the speakers. Also, I did room correction with 0 and 180 phase but the 0 phase sounded off in the bass. I was listening the same music and with phase 0 the bass sometimes missed, like on and off it was weird. I stayed with 180.
Oh, and the dip around 100hz is less obvious with the 180 phase.

So, currently I'm getting to used the less bass in my system but probably I'll ending up EQ a bit for more bass.
Here are my measurements with the calibrated microphone.

The automatic sub/speaker sync shouldn't give the same delay for 0 and 180 degrees. The original wrongly implemented version also gave the same delay for 0/180 when I tried it when it was first introduced. I have no idea if that was ever fixed.

 

[mosquito007]

The automatic sub/speaker sync shouldn't give the same delay for 0 and 180 degrees. The original wrongly implemented version also gave the same delay for 0/180 when I tried it when it was first introduced. I have no idea if that was ever fixed.

To be fair I honestly don't know what's right or not. I'm newbie
I did a quick sub speaker sync now toggle between 0 and 180 phase in the Wiim app and the results was 8ms to the speakers in both cases.
When I switched the phase 180 in the SVS app and same 180 in the Wiim app then I saw higher 18ms delay to the speakers.
I'm using phase in the SVS app 0 and the room correction was 180 phase in the Wiim app.
I'm not sure this is right but with phase 0 in the Wiim app the bass was off.

 

[juggle]

The image below is a screenshot used in a subwoofer related document titled "Subwoofer Calibration: One-Tap Sync between Main Speakers and Subwoofer at the Listening Position", which is posted on April 15, 2026.



Source: https://faq.wiimhome.com/en/support...akers-and-subwoofer-at-the-listening-position


The red box area looks different from the UI of the WiiM Home App I’m currently running. Do you guys also see the same UI as the one shown in the posted document?

 

[slartibartfast]

To be fair I honestly don't know what's right or not. I'm newbie
I did a quick sub speaker sync now toggle between 0 and 180 phase in the Wiim app and the results was 8ms to the speakers in both cases.
When I switched the phase 180 in the SVS app and same 180 in the Wiim app then I saw higher 18ms delay to the speakers.
I'm using phase in the SVS app 0 and the room correction was 180 phase in the Wiim app.
I'm not sure this is right but with phase 0 in the Wiim app the bass was off.

I believe your results. I am just surprised that WiiM released the feature with an obvious bug. @WiiM Team why is the sub/speaker sync delay exactly the same when the the phase is switched between 0 and 180 degrees?

 

[slartibartfast]

The image below is a screenshot used in a subwoofer related document titled "Subwoofer Calibration: One-Tap Sync between Main Speakers and Subwoofer at the Listening Position", which is posted on April 15, 2026.

View attachment 37213

Source: https://faq.wiimhome.com/en/support...akers-and-subwoofer-at-the-listening-position


The red box area looks different from the UI of the WiiM Home App I’m currently running. Do you guys also see the same UI as the one shown in the posted document?

The subwoofer level is a new feature only available with new firmware presumably.

 

[mosquito007]

I believe your results. I am just surprised that WiiM released the feature with an obvious bug. @WiiM Team why is the sub/speaker sync delay exactly the same when the the phase is switched between 0 and 180 degrees?

Maybe because it's not taking into account the subwoofer phase but I'm just speculating. Who knows.

 

[slartibartfast]

Maybe because it's not taking into account the subwoofer phase but I'm just speculating. Who knows.

That's how it looks but the purpose of the feature is to synchronise the phase of the subwoofer and the speakers at and around the crossover frequency. For example I can get very similar results by delaying the main speakers by 5ms or switching the phase to 180 degrees with no delays so I would expect the automatic sync to produce the same results. If it doesn't it isn't fit for purpose.
When I get the new firmware for the Amp it will be the first thing I test