Wiim Amp Ultra new subwoofer sync

[mosquito007]

Hi guys newbie here just be patient,

Today I received the new firmware for Wiim Amp Ultra and I was looking forward to try the new implementation of the subwoofer sync with speakers. ATM I have set up my crossover frequency at 80hz and my sub is next to my left speaker, nearly same distance. The previous fw always gave me +8ms delay consistently same as the new firmware with multiple measurements. However I wanted to lower my crossover frequency to 50hz because my speakers can go down as low as 36hz Monitor Audio Bronze 100 6g but with the new firmware the subwoofer sync is +26ms consistently to the main speakers. I did some research and it says above 20ms is too excessive but what do I know that's why I'm asking?
The speakers are 2.0m apart, to my listening position is 2.1m and my sub is 2.67m.

So, I would like to ask your opinion about that.
Thank you

 

[hipoagumol]

Change the phase setting at wiim sub output and measure again. Keep the phase there gives lowest delay. I think the delay you are measuring is accounting for a complete cycle ahead signal probably because of phase of sub is reversed to mains.

 

[mosquito007]

Change the phase setting at wiim sub output and measure again. Keep the phase there gives lowest delay. I think the delay you are measuring is accounting for a complete cycle ahead signal probably because of phase of sub is reversed to mains.

Are you saying that my phase settings was out? Just because when I measured it the highest dB was at the current settings, which is 0° and was lowest at 180°.
Just to be clear, set the phase, sub sync and then room correction?

 

[harkpabst]

Are you saying that my phase settings was out? Just because when I measured it the highest dB was at the current settings, which is 0° and was lowest at 180°.

We cannot know this for sure, but at least it seems very likely. As @hipoagumol said, perform the sync function with the phase switch in the WiiM Home App set to 0⁰, record the latency value, then repeat with the phase switch set to 180⁰. Whichever position results in the lower latency value should be preferable.

Just to be clear, set the phase, sub sync and then room correction?

Yes, that's the correct order.

As per above, with such surprisingly high latency values try both phase settings for the sync. At least initially there's no reason to run RoomFit for each phase setting.

If you still find that RoomFit shows a somewhat broader dip in the frequency response right at the crossover frequency you can still flip the phase switch any time, just to check if it makes a difference. It really shouldn't and there are other reasons for dips in the frequency response, if course, but if a dip can be cured by reverting the polarity (that's what the phase switch really does) at all, then by all means it should be done.

Let us know how you get along. The corrected sync function using the phone's mic is still pretty new and everybody's interested in the results.

 

[Wiimer]

I remember a few members reporting that the new sync feature wasn’t working properly. There might be a bug, so it might be a good idea to move the microphone and run a few tests to verify this. I haven’t been able to test it myself yet, though...

 

[mosquito007]

We cannot know this for sure, but at least it seems very likely. As @hipoagumol said, perform the sync function with the phase switch in the WiiM Home App set to 0⁰, record the latency value, then repeat with the phase switch set to 180⁰. Whichever position results in the lower latency value should be preferable.


Yes, that's the correct order.

As per above, with such surprisingly high latency values try both phase settings for the sync. At least initially there's no reason to run RoomFit for each phase setting.

If you still find that RoomFit shows a somewhat broader dip in the frequency response right at the crossover frequency you can still flip the phase switch any time, just to check if it makes a difference. It really shouldn't and there are other reasons for dips in the frequency response, if course, but if a dip can be cured by reverting the polarity (that's what the phase switch really does) at all, then by all means it should be done.

Let us know how you get along. The corrected sync function using the phone's mic is still pretty new and everybody's interested in the results.

Thanks guys all the advice.
Just did that little experiment but my problem is when I lower the crossover frequency the latency increases a lot.
Subwoofer phase @ 0° 80hz crossover 8ms
Subwoofer phase @180° 80hz crossover 5ms
Subwoofer phase @0° 50hz crossover 26ms
Subwoofer phase @180° 50hz crossover 71ms

As you can see the measurements are consistent every time the same value like above, and measured with phone mic.
So now I'm confused which is the right settings or just keep the crossover @80hz?

 

[BMeek]

Do your RoomFit results with the lower crossovers show any strong dips between your 50Hz and 80Hz range?

I'm in the 'just knowledgeable enough to be dangerous' phase of this hi-fi hobby, but I'm theorizing that when the low frequencies shift from the corner sub to the main woofers, a strong SBIR null from a surface within a meter or two from the main speaker(s) might be confusing the SubSpeakerSync process. Whether or not such a null could be strong enough to cause the SubSpeakerSync function to miss it's cue on the bass response, I have no idea.

 

[Goodnews]

With 2 subwoofers, following today's update

 

[mosquito007]

Do your RoomFit results with the lower crossovers show any strong dips between your 50Hz and 80Hz range?

I'm in the 'just knowledgeable enough to be dangerous' phase of this hi-fi hobby, but I'm theorizing that when the low frequencies shift from the corner sub to the main woofers, a strong SBIR null from a surface within a meter or two from the main speaker(s) might be confusing the SubSpeakerSync process. Whether or not such a null could be strong enough to cause the SubSpeakerSync function to miss it's cue on the bass response, I have no idea.

I don't have the measurements with the lower crossover but I have the measurements with the 80hz crossover plus sub. I'm working ATM but I'll play with the system tomorrow.
There's some dip in the raw measurement but it's gone after the room correction, however I always had big dip around 100hz with or without subwoofer on the measurements. See the photos.

 

[adias]

Does this new sync also work with WiiM Sub Pro connected via WiFi?

 

[mosquito007]

Hi guys @BMeek @harkpabst
It seems to me that the sub sync measurements each day are inconsistent.
I did sub sync with 50hz crossover and I got different results than yesterday.
Phase @0° was 25ms and @180° was 55ms
After each sub sync I did room correction and in both cases the results was mostly similar to me (amateur)
However after the room correction of phase 180 I did again sub sync and to my surprise the delay went down to 3ms to subwoofer. Thereafter I did again a room correction and seems to me that the dips around 50hz and 100hz disappeared. For my eyes this looks better but correct me if I'm wrong.
So I'm now totally lost it what's correct and what's not.
See the measurements
Thanks again.

 

[xnobex]

One day I have 34ms, another day 41ms with same cross and everything.

 

[BMeek]

Hi guys @BMeek @harkpabst
It seems to me that the sub sync measurements each day are inconsistent.
I did sub sync with 50hz crossover and I got different results than yesterday.
Phase @0° was 25ms and @180° was 55ms
After each sub sync I did room correction and in both cases the results was mostly similar to me (amateur)
However after the room correction of phase 180 I did again sub sync and to my surprise the delay went down to 3ms to subwoofer. Thereafter I did again a room correction and seems to me that the dips around 50hz and 100hz disappeared. For my eyes this looks better but correct me if I'm wrong.
So I'm now totally lost it what's correct and what's not.
See the measurements
Thanks again.

Huh. The last two graphs of your RoomFit results at a 50Hz crossover do indeed look better. Zooming in I'm pleasantly surprised that the raw [grey line] dips at ~55Hz and ~100Hz appear pretty well-mitigated in the measured results [cyan line]. I would normally want to edit/eliminate or reduce any resulting PEQ filter boosts that frequently represent RoomFit's counter-productive attempt to eliminate an SBIR null. Nonetheless, the boost at the ~100+Hz raw sharp dip seems to have helped tame (rather than exacerbate) said dip. Perhaps someone more knowledgable will enlighten us .



Does it sound better to you now?

 

[mosquito007]

Huh. The last two graphs of your RoomFit results at a 50Hz crossover do indeed look better. Zooming in I'm pleasantly surprised that the raw [grey line] dips at ~55Hz and ~100Hz appear pretty well-mitigated in the measured results [cyan line]. I would normally want to edit/eliminate or reduce any resulting PEQ filter boosts that frequently represent RoomFit's counter-productive attempt to eliminate an SBIR null. Nonetheless, the boost at the ~100+Hz raw sharp dip seems to have helped tame (rather than exacerbate) said dip. Perhaps someone more knowledgable will enlighten us .

View attachment 36833

Does it sound better to you now?

It seems to me better especially in the lower frequencies. Less boomy, bass more punchier. However did some digging and according that the 3ms delay shouldn't be applied to the subwoofer because its farther away from my listening position than the speakers. It should be the opposite way.
So I really don't know what's going on. Hopefully someone will enlighten us about this.

 

[s3igell]

Remember that RoomFit / BassFit isn't a Tape Measure, but rather the application of Math to the mix of Sound Pressure Waves comparing their relative Frequency, Timing, and Strength. Factors could include the DSP function and Timing, the Inductance of the CrossOvers in the Speakers, and even the Room Reflections

 

[juggle]

I’m seeing the same issue. Previously, the subwoofer delay was +8ms, but after updating to firmware version 5.2.813259 it has increased to +52ms.

My setup is Monitor Audio Gold 50 6G with a REL Acoustics Tzero MKIII, paired with a WiiM Ultra and WiiM Vibelink Amp. For reference, nothing else has changed except the firmware.

Interestingly, the +52ms delay actually sounds better to me, though I’m not entirely sure why.

 

[satheesht]

Interestingly, the +52ms delay actually sounds better to my ears, though I’m not entirely sure why

Before the new feature was released ( measurement from listening position using app is new feature) the automatic delay feature measured that my speaker delay should be set to +6ms to sync rhe sub. I also validated it with an android app which plays a drum with hihat so that we can hear if there is any timing difference and I couldn't hear any. So i kept it. Then on a thread for roomfit, an expert told me that it's incorrect as the distance between my speakers and sub and the small circuitry in the sub doesn't warrant that delay. Then with manual steps after setting phase to 180 degree, we concluded and set the delay at 3ms. Now with the new feature it's measuring as 2ms as phase 180.

If 52ms is not justified by physical distance between the speakers and sub, then it's definitely a result of wrong phase setting or wrong measurement by the app or both as the processing delay difference even with complex electronics on a sub cannot be more than 2 to 4 ms (I heard this from folks on that thread.). May be it sounds ok because sub frequency waves have the longest wave length and when they are in sync phase wise and we hear that based on sound pressure level match.

For reference, in my car where sub is in the boot and speakers are very close to the ears, the delay I measured is 5.8ms. For the car which is a closed enclosure I followed a method of playing sine tone at crossover frequency and measuring SPL levels using an app while adjusting the delay setting. Might work in a silent room as well.

(Process for car was to set an initial delay based on physical measurement, flip the phase, play sine wave pulse at crossover frequency and measure SPL using an app, then find the delay which has lowest spl. Then flip the phase to confirm its highest SPL)

 

[hipoagumol]

Sorry to hear that the sub main sync feature might be buggy. Has anyone created a ticket towards wiim?
I also randomly got such high delays with previous (measured from devices mic) firmware version. Then other times got normal small delays... but other times sub delayed when it is further than mains..That lack of consistency left me doubtful and decided to wait for next version...which seems not to solve it.
Manual delay setting looks now the only way forward...

 

[juggle]

When I re‑measured using the miniDSP UMIK‑1 calibration microphone, the delay actually went up—from +52ms to +73ms. Adjusting the phase didn’t really change much.

The more I think about it, syncing the main speakers with the subwoofer isn’t just about the distance between the speakers and the listener. There are other factors at play.

For example, in my setup the main speakers follow this path:

WiiM Ultra → (optical out) → WiiM Vibelink Amp → (speaker out) → MA Gold 50 6G

Meanwhile, the subwoofer takes a different route:

WiiM Ultra → (LFE) → REL Tzero MKIII

Since the devices in each chain are different, they may handle amplification in different ways, apply DSP, or convert signals differently (like optical to electrical). So a measured delay of more than +10ms might not necessarily mean there’s a measurement error or a software bug.

That leaves me with two questions:

1. Could the increased delay just be a reflection of the differences in the signal chain?
2. Is there a reliable way to test whether the sync is actually working properly?