Beta Test: Automatic timing alignment for Main Speakers and Subwoofer

[harkpabst]

I have just become aware that the iOS app Housecurve does automatic subwoofer timing alignment so someone with Housecurve would be the ideal tester for this feature. Far better than relying on me. Is anyone else even taking part in this beta testing?

Should the results differ, you still don't know which is more accurate.

Not until you measure and listen, that is.

 

[WiiM Support]

Hi Team,

The auto-calibration feature is designed to improve audio quality by aligning the timing between your main speaker and subwoofer. When a WiiM device, like the WiiM Amp or WiiM Ultra, connects to your speaker and subwoofer, it assumes both audio paths have the same delay. However, if your powered speaker, amplifier or subwoofer adds extra audio processing, it can introduce a slight delay.

This mismatch in timing can cause the high and low frequencies from your main speaker and subwoofer to sound out of sync, affecting the overall audio quality. Our auto-calibration feature uses the device’s built-in microphone to detect and adjust these timing differences, ensuring a better blend of sound.

This approach is different from Housecurve, which may use your phone's MIC to calibrate the audio at your listening position. Our focus here is on achieving synchronized audio between the main speakers and the subwoofer for a more seamless listening experience.

---

 

[slartibartfast]

Should the results differ, you still don't know which is more accurate.

Not until you measure and listen, that is.

If they don't differ though you can probably trust them.

 

[slartibartfast]

Hi Team,

The auto-calibration feature is designed to improve audio quality by aligning the timing between your main speaker and subwoofer. When a WiiM device, like the WiiM Amp or WiiM Ultra, connects to your speaker and subwoofer, it assumes both audio paths have the same delay. However, if your powered speaker, amplifier or subwoofer adds extra audio processing, it can introduce a slight delay.

This mismatch in timing can cause the high and low frequencies from your main speaker and subwoofer to sound out of sync, affecting the overall audio quality. Our auto-calibration feature uses the device’s built-in microphone to detect and adjust these timing differences, ensuring a better blend of sound.

This approach is different from Housecurve, which may use your phone's MIC to calibrate the audio at your listening position. Our focus here is on achieving synchronized audio between the main speakers and the subwoofer for a more seamless listening experience.

---

When you say it uses the device's built in mic do you mean the phone mic? What happens if an external mic is used?
I read that Housecurve also has a timing alignment feature so I don't understand how that can be a different approach. I am now more confused by your clarification than I was before

 

[harkpabst]

This is interesting to know.

Our auto-calibration feature uses the device’s built-in microphone to detect and adjust these timing differences, ensuring a better blend of sound.

I see how this approach can correct delay caused by the signal processing under the assumption that the listening distance to sub and mains is similar. It's not quite obvious to me how it could e.g. deal with a sub placed further away from the speakers, e.g. close to a side wall or maybe even behind the MLP, as some people set it up.

One could argue that in these cases the crossover frequency must be so low that the offset doesn't matter much.

 

[harkpabst]

When you say it uses the device's built in mic do you mean the phone mic? What happens if an external mic is used?

Don't think so.

This approach is different from Housecurve, which may use your phone's MIC to calibrate the audio at your listening position.

This is pretty clear.

 

[slartibartfast]

Don't think so.

This is pretty clear.

I don't understand how it works at all then. How does it measure the delay? Does it depend on where the device is relative to the speakers?

 

[slartibartfast]

Having read that I would be more inclined to believe Housecurve. Maybe it explains why flipping the phase has no effect.

 

[Wiimer]

Hi Team,

The auto-calibration feature is designed to improve audio quality by aligning the timing between your main speaker and subwoofer. When a WiiM device, like the WiiM Amp or WiiM Ultra, connects to your speaker and subwoofer, it assumes both audio paths have the same delay. However, if your powered speaker, amplifier or subwoofer adds extra audio processing, it can introduce a slight delay.

This mismatch in timing can cause the high and low frequencies from your main speaker and subwoofer to sound out of sync, affecting the overall audio quality. Our auto-calibration feature uses the device’s built-in microphone to detect and adjust these timing differences, ensuring a better blend of sound.

This approach is different from Housecurve, which may use your phone's MIC to calibrate the audio at your listening position. Our focus here is on achieving synchronized audio between the main speakers and the subwoofer for a more seamless listening experience.

---

Hi @WiiM Support,

Is that basically the same mechanism as Auto-sync on the WiiM?

If so, can I expect the same effect if I run Auto-sync with two subwoofers connected to the Pro's line-out instead of using the Ultra's sub-outs?

My current system looks like this
Ultra >> Main Speakers
Pro >> (Line-out) >> Subwoofer *2

And I am playing these two WiiMs in a group, do you think it would be better to put the Ultra in the listening position before running auto-sync on the Ultra and Pro?

Or would it be better to use one Ultra (or Amp) for the left channel and one for the right channel, with a subwoofer connected to each channel's sub out?

In this case, the system would look like this.
Ultra 1 >> (amp) >> Left Speaker
>> (Sub-out) >> Left Subwoofer
Ultra 2 >> (amp) >> Right Speaker
>> (Sub-out) >> Right Subwoofer

Thank you.

 

[slartibartfast]

This is interesting to know.



I see how this approach can correct delay caused by the signal processing under the assumption that the listening distance to sub and mains is similar. It's not quite obvious to me how it could e.g. deal with a sub placed further away from the speakers, e.g. close to a side wall or maybe even behind the MLP, as some people set it up.

One could argue that in these cases the crossover frequency must be so low that the offset doesn't matter much.

My subwoofer doesn't have any signal.processing but moving the subwoofer gave me a different timing delay.

 

[jxrxme]

Our auto-calibration feature uses the device’s built-in microphone to detect and adjust these timing differences, ensuring a better blend of sound.

Can @WiiM Support clarify which microphone is used? Remote‘s microphone? Is there a microphone built-in into the Amp?

 

[harkpabst]

Is there a microphone built-in into the Amp?

Yes. The microphone built into the device. I really don't see where all the confusion is coming from.

My subwoofer doesn't have any signal.processing but moving the subwoofer gave me a different timing delay.

The single microphone built into the device can measure the effective distance from the device to each speaker, including the sub and including any latency introduced by the speaker itself. It can draw a virtual circle around the device on which each loudspeaker could stand. WiiM might perform some more trickery like observing the first of dominant reflection. Not sure if they are interested in posting all details of their algorithm.

 

[slartibartfast]

Now I know the measurement doesn't take account of the phase relationship at the crossover frequency (which is the main purpose of timing alignment as far as I know) I'll go back to my manual setting and forget about the automatic timing alignment. The fact that switching the phase by 180 degrees didn't affect the delay should have been a warning.

 

[slartibartfast]

Yes. The microphone built into the device. I really don't see where all the confusion is coming from.


The single microphone built into the device can measure the effective distance from the device to each speaker, including the sub and including any latency introduced by the speaker itself. It can draw a virtual circle around the device on which each loudspeaker could stand. WiiM might perform some more trickery like observing the first of dominant reflection. Not sure if they are interested in posting all details of their algorithm.

One speaker is much closer to the amp than the other. I've lost all faith in the automatic timing now.

 

[jxrxme]

Yes. The microphone built into the device. I really don't see where all the confusion is coming from.


The single microphone built into the device can measure the effective distance from the device to each speaker, including the sub and including any latency introduced by the speaker itself. It can draw a virtual circle around the device on which each loudspeaker could stand. WiiM might perform some more trickery like observing the first of dominant reflection. Not sure if they are interested in posting all details of their algorithm.

Well, the Amp/Ultra shouldn’t be in a hidden position far away then. I can imagine installations where the Amp isn’t even in the same room with the speakers…
In my case the Amp is stored in cabinet but should be able to hear all speakers…

 

[slartibartfast]

Now I have received this from support.
"We’re aware of an issue where phase settings aren’t applying correctly during the Automatic Timing Alignment for the main speakers and subwoofer. Our team is actively working on a fix, so please stay tuned for updates!"

 

[WiiM Support]

When you say it uses the device's built in mic do you mean the phone mic? What happens if an external mic is used?
I read that Housecurve also has a timing alignment feature so I don't understand how that can be a different approach. I am now more confused by your clarification than I was before

Apologies for the confusion - I was referring to the mic on the WiiM device.

Also, please note that the current setup doesn’t account for the distance between your listening position and your subwoofer or main speakers. For the best sound adjustment, it helps to know the exact distance from your listening position to each speaker. Otherwise, further calibration may be needed, ideally using a mic placed at your listening position.

 

[Wiimer]

. Otherwise, further calibration may be needed, ideally using a mic placed at your listening position.

To repeat my earlier question, what happens if I place a WiiM device in the listening position?

 

[slartibartfast]

Apologies for the confusion - I was referring to the mic on the WiiM device.

Also, please note that the current setup doesn’t account for the distance between your listening position and your subwoofer or main speakers. For the best sound adjustment, it helps to know the exact distance from your listening position to each speaker. Otherwise, further calibration may be needed, ideally using a mic placed at your listening position.

So it doesn't do what we were lead to believe it would do, i.e. optimising phase at the crossover point.

 

[harkpabst]

It was never intended to change the "phase" setting, but the phase relation between mains and sub. This is ontrolled through the latency.

The "phase" switch changes the polarity. It's a misnomer, even if a common one.