Wiim Amp Ultra - Polk Audio XT20 & SVS SB 1000 Pro - Configuration

[dominikz]

Ok, I redid the subwoofer layout according to your advice. Now it is in the corner of the other wall between the sofa and the wall.
I slightly widened the distance between the speakers (now it is 2.60 meters)
I moved the speakers forward another 10 cm.

Below is the new layout and the graphs.

That looks significantly better than before!

Some questions before I make any more suggestions:

1. What values for speaker/sub latency/delay have you configured at the moment in the WiiM app?
2. What is the current distance from the SVS sub to your listening position, compared to each Polk speaker to your listening position?
3. How did you set subwoofer volume (on the sub itself and in the WiiM app)?
4. Do you at the moment have any PEQs configured in the SVS app?

The bass part seems better than before but the high part has the usual peak and I don't know how to reduce it

Don't worry about the high frequency peak at 8000Hz - the peak is "added" by your phone microphone and doesn't really exist.
The only good way to 'reduce' this peak in the graphs is to use a better microphone when doing RC (ideally you'd use a calibrated measurement microphone).

 

[Andrew78]

That looks significantly better than before!

Some questions before I make any more suggestions:

1. What values for speaker/sub latency/delay have you configured at the moment in the WiiM app?
2. What is the current distance from the SVS sub to your listening position, compared to each Polk speaker to your listening position?
3. How did you set subwoofer volume (on the sub itself and in the WiiM app)?
4. Do you at the moment have any PEQs configured in the SVS app?

Don't worry about the high frequency peak at 8000Hz - the peak is "added" by your phone microphone and doesn't really exist.
The only good way to 'reduce' this peak in the graphs is to use a better microphone when doing RC (ideally you'd use a calibrated measurement microphone).

Sorry you're right! Below are the answers:

1. What values for speaker/sub latency/delay have you configured at the moment in the WiiM app? --> 8 ms on the speakers
2. What is the current distance from the SVS sub to your listening position, compared to each Polk speaker to your listening position? --> I have attached the floor plan with the measurements
3. How did you set subwoofer volume (on the sub itself and in the WiiM app)? --> - 13 dB on SVS and +3 db on Wiim App (phase 0°)
4. Do you at the moment have any PEQs configured in the SVS app? --> Yes I used a PEQ setting to improve the bass response (see attachment)

Attached you will find all the current settings

 

[dominikz]

Sorry you're right! Below are the answers:

1. What values for speaker/sub latency/delay have you configured at the moment in the WiiM app? --> 8 ms on the speakers
2. What is the current distance from the SVS sub to your listening position, compared to each Polk speaker to your listening position? --> I have attached the floor plan with the measurements
3. How did you set subwoofer volume (on the sub itself and in the WiiM app)? --> - 13 dB on SVS and +3 db on Wiim App (phase 0°)
4. Do you at the moment have any PEQs configured in the SVS app? --> Yes I used a PEQ setting to improve the bass response (see attachment)

Attached you will find all the current settings

Ok, so looks like at the moment the direct distance from the listening position to the sub is 1,6m, while the direct distance from the listening position to each Polk speaker should be around ~2,3m (not marked in your diagram but can easily be calculated using the Pythagoras' theorem).

That means that the direct like to the sub is ~0,7m shorter than to the speakers so the sound from the sub takes about ~2ms less to reach you compared to the sound from the Polk speakers. We also assume that the SVS sub DSP adds about 6ms latency so total latency for the speakers at the new location should be 6ms - 2ms = 4ms.

Taking all of this into account, I'd suggest the following settings with this new layout:

SVS app settings:

• All PEQs disabled
• Low pass filter disabled
• Volume set to -5dB

WiiM Home App "Subwoofer" menu settings:

• Level: 0dB
• Crossover Frequency: 80Hz
• Manual delay/latency setting:
  • Loudspeakers: +4ms
  • Subwoofer: 0ms

WiiM Home App "Room Correction" menu settings:

• Target Curve = B&K
• Freq = 20 - 150 Hz
• Max Gain = +3 dB
• Min Gain = -12 dB
• Max Q = 10
• Smoothing = 1/12 Octave
• Subwoofer Calibration = Enabled
• Multiple Measurements = Enabled
• Moving Mic Measurement = Disabled
• Precision Room Correction = Disabled
• Use "Individual Channel Room Correction"

With the changes I proposed above you should get a bit more level out of the sub prior to RC, and the RC filters should be better allocated to the problem areas so I hope you will get a smoother bass response as a result.

Re-run RC after changing all of this and see if you get any improvement. Depending on the results we may or may not need to tweak a bit more. Good luck!

 

[Andrew78]

Ok, so looks like at the moment the direct distance from the listening position to the sub is 1,6m, while the direct distance from the listening position to each Polk speaker should be around ~2,3m (not marked in your diagram but can easily be calculated using the Pythagoras' theorem).

That means that the direct like to the sub is ~0,7m shorter than to the speakers so the sound from the sub takes about ~2ms less to reach you compared to the sound from the Polk speakers. We also assume that the SVS sub DSP adds about 6ms latency so total latency for the speakers at the new location should be 6ms - 2ms = 4ms.

Taking all of this into account, I'd suggest the following settings with this new layout:

SVS app settings:

• All PEQs disabled
• Low pass filter disabled
• Volume set to -5dB

"Subwoofer" menu settings:

• Level: 0dB
• Crossover Frequency: 80Hz
• Manual delay/latency setting:
  • Loudspeakers: +4ms
  • Subwoofer: 0ms

"Room Correction" menu settings:

• Target Curve = B&K
• Freq = 20 - 150 Hz
• Max Gain = +3 dB
• Min Gain = -12 dB
• Max Q = 10
• Smoothing = 1/12 Octave
• Subwoofer Calibration = Enabled
• Multiple Measurements = Enabled
• Moving Mic Measurement = Disabled
• Precision Room Correction = Disabled
• Use "Individual Channel Room Correction"

With the changes I proposed above you should get a bit more level out of the sub prior to RC, and the RC filters should be better allocated to the problem areas so I hope you will get a smoother bass response as a result.

Re-run RC after changing all of this and see if you get any improvement. Depending on the results we may or may not need to tweak a bit more. Good luck!

I checked the direct distance from the listening position to each Polk speaker is around ~ 2,20m
Ok, I updated the configuration according to your settings. Attached are the new graphs
How does it seem to you?

 

[Andrew78]

Sorry I forgot to activate the bluetooth of the svs and I did not set the correct parameters.
Now are ok!
Ignore the previous graphs and use these in attachment

 

[dominikz]

Sorry I forgot to activate the bluetooth of the svs and I did not set the correct parameters.
Now are ok!
Ignore the previous graphs and use these in attachment

Before we try anything else, how does it sound to you now subjectively?
Any improvement compared to where we started? Any audible issues?

 

[Andrew78]

In my opinion, changing the position of the subwoofer definitely made a positive difference, and I have to say that the entire musical soundstage has improved!
Of course, there's always room for further improvement, but I feel like and i think I'm already in a good place.
In short, I can see the light at the end of the tunnel!
Thanks to everyone who helped and supported me!"

Before we try anything else, how does it sound to you now subjectively?
Any improvement compared to where we started? Any audible issues?

 

[dominikz]

In my opinion, changing the position of the subwoofer definitely made a positive difference, and I have to say that the entire musical soundstage has improved!
Of course, there's always room for further improvement, but I feel like and i think I'm already in a good place.
In short, I can see the light at the end of the tunnel!
Thanks to everyone who helped and supported me!"

That is really great to hear!
At the moment I believe your results are mainly limited by a few known issues with current RC implementation in WiiM.

One easy thing you can try is to set RC Min Gain to -12dB and Max Gain to +12dB and see if you get a flatter bass response with that.

A less easy thing to try would be to measure with REW and a measurement microphone, and to generate PEQ correction filters on a PC - which you would then manually configure in WiiM PEQ.
This is more complicated to do, but also much more flexible than WiiM RC.

But if you like the sound you are getting (and aren't interested in the technicalities) then there's maybe no need to tweak further - just enjoy the music!

 

[ericthefish]

As an outside observer, this conversation has been fascinating.... Thanks to everyone for contributing. I will try a few things noted in here.

 

[vbutani]

Hello! That is a pretty nice set of gear! At the moment your bass response is not ideal, but I'm sure it can be improved with some tweaking.

May I first suggest to have a look at this FAQ article for guidance on basic speaker/subwoofer placement and Room Correction (RC) settings? The article content is based on this post.

A few general comments regarding the article content:

• This is not mentioned explicitly, but it is assumed you will use the "Individual Channel Room Correction" variant when the option is presented.
• Article was written prior to separation of min and max gain in WiiM RC. Due to a limitation of current WiiM RC algorithm I suggest to start with Min Gain = -12dB and Max Gain +3dB.
• Unfortunately WiiM automatic "Subwoofer & Speakers Sync" function is not really implemented well for subwoofer integration, since it uses the bult-in microphone of the WiiM device which is not normally located at the listening position - so the relative delays can be way off in practice. See e.g. this post for reference. As a result, I recommend to use manual time alignment instead (a bit more on this below).
• Loudspeaker and subwoofer placement is key for good bass quality and should be optimized as best as possible prior to running RC - this cannot be overstated. I've provided some argumentation for my placement recommendations in this post. I also suggest to read this article by Genelec.
• Recently another member was struggling with a similar situation, and we provided guidance to him in this thread - the bass response was improved significantly (see result here) by tweaking placement and WiiM RC settings.

Another key factor for bass quality is subwoofer integration. This is IMHO best tweaked with the free REW software (link), and again should be done before running final RC. The main intention is to:

• Avoid the response dip/cancellation at the crossover frequency by tweaking subwoofer phase and delay.
  • Note that you will need to take into account both the sound propagation time delay due to difference in sub/speaker distance to your listening position (roughly 3ms for every 1m of distance difference), as well as the delay introduced by the subwoofer on-board DSP. Based on this post, the SVS SB-1000 Pro DSP should introduce 6ms of delay. However if you can measure phase and group delay of your individual loudspeakers and your subwoofer at your listening position with REW that would be best for precise alignment.
• Get subwoofer aligned in level to the main loudspeakers by tweaking the sub level control. It is better to have the sub slightly louder than the speakers initially, as any peaks will be knocked down later by RC.

Lastly, I see you are using your phone microphone to calibrate; this is what is causing the massive peak at 8kHz in your response measurements.
If you can get your hands on a calibrated measurement mic (like e.g. miniDSP UMIK-1 or Dayton iMM-6c) that should make your RC calibrations (and REW measurements) much more reliable.

Hope this helps and have fun!

Thanks for the detailed guide. Would it be possible to share some reference guide or video links of REW to measure delay and other required measurements. I checked high-level at youtube videos but most of them related to AVR setup.

I have SVS SB1000 pro subwoofer and I'm facing the bass management related issues as my wiim ultra is in the tv unit cabinet. I have Umik1 and very basic knowledge of measuring speaker frequency response using REW. Thanks in advance.

 

[EddNog]

Thanks for the detailed guide. Would it be possible to share some reference guide or video links of REW to measure delay and other required measurements. I checked high-level at youtube videos but most of them related to AVR setup.

I have SVS SB1000 pro subwoofer and I'm facing the bass management related issues as my wiim ultra is in the tv unit cabinet. I have Umik1 and very basic knowledge of measuring speaker frequency response using REW. Thanks in advance.

Copying & pasting a post of mine from elsewhere in the forum:
To determine latency, you need to use REW. You would have to use either Bluetooth or optical input from your computer with the UMIK-1 attached. Sweep range needs to be around the crossover (so if you cross over around 80Hz, use a sweep range like 60-200Hz), use an acoustic timing reference from the nearest speaker, and make sure to disable the actual crossover in Subwoofer settings (subwoofer and speakers should be set to full bandwidth) as well as the speaker or subwoofer delays must be reset to 0ms to get an accurate read. There are tutorials across the web on how to configure REW. Done right, REW tells you the delay in the notes for each sweep. Even the reference speaker will have a delay, you need to subtract that from the delay for all channels. Because you can’t mute any specific outputs, you’ll need to manually connect/disconnect the speaker you’re testing, so using REW as an example let’s say you decide to use left speaker as acoustic reference, first step turn off the subwoofer, set acoustic reference as left channel and playback as left channel, run the sweep (preferably 3 or more times and take an average of the delays indicated), then to measure right speaker, change output to right channel and do it again, your delay should be extremely close to left channel since the speakers should be very close to the same distance to the listening position, then disconnect the right speaker, turn the subwoofer on, and with right channel still set as output run some more sweeps and you’ll have your delay for the sub (since WiiM will sum left and right channels together to send to the sub).

So let’s say left and right sub are about 2ms and subwoofer is 9ms then you want to delay speakers 7ms. Be careful of the direction of the delays, so for example if speakers are -2ms and subwoofer is 9ms then you must delay 11ms.

Here are the running tables/calcs from my last few sessions of REW. Notice the negative delays for the speakers. I think the math is self-explanatory:


The shorter delay for the big sub is fascinating because that sub is actually fed off the same miniDSP unit as the two small subs, and theoretically should have the same DSP-induced delay internally. I would not say that it is placed significantly closer to the main listening position:


-Ed

 

[Andrew78]

Hi everyone

A little update: I bought the DaytonAudio iMM6-C, downloaded the calibration file, and re-ran the room correction. Here are the results.
I have to say, I'm satisfied.

these are the configuration parameters used:
SVS app settings:

• All PEQs disabled
• Low pass filter disabled
• Volume set to -5dB

WiiM Home App "Subwoofer" menu settings:

• Level: 0dB
• Crossover Frequency: 80Hz
• Manual delay/latency setting:
  • Loudspeakers: +4ms
  • Subwoofer: 0ms

WiiM Home App "Room Correction" menu settings:

• Target Curve = B&K
• Freq = 20 - 150 Hz
• Max Gain = +3 dB
• Min Gain = -12 dB
• Max Q = 10
• Smoothing = 1/12 Octave
• Subwoofer Calibration = Enabled
• Multiple Measurements = Enabled
• Moving Mic Measurement = Disabled
• Precision Room Correction = Disabled
• Use "Individual Channel Room Correction"

These are the results:



Final calibration:

 

[dominikz]

Hi everyone

A little update: I bought the DaytonAudio iMM6-C, downloaded the calibration file, and re-ran the room correction. Here are the results.
I have to say, I'm satisfied.

these are the configuration parameters used:
SVS app settings:

• All PEQs disabled
• Low pass filter disabled
• Volume set to -5dB

WiiM Home App "Subwoofer" menu settings:

• Level: 0dB
• Crossover Frequency: 80Hz
• Manual delay/latency setting:
  • Loudspeakers: +4ms
  • Subwoofer: 0ms

WiiM Home App "Room Correction" menu settings:

• Target Curve = B&K
• Freq = 20 - 150 Hz
• Max Gain = +3 dB
• Min Gain = -12 dB
• Max Q = 10
• Smoothing = 1/12 Octave
• Subwoofer Calibration = Enabled
• Multiple Measurements = Enabled
• Moving Mic Measurement = Disabled
• Precision Room Correction = Disabled
• Use "Individual Channel Room Correction"

These are the results:

View attachment 28104

Final calibration:

View attachment 28105

Good to hear you are happy with your system! Investment in a measurement mic is IMHO a very good one.

Regarding your response, there are still some pretty severe response dips at 30Hz and about 43Hz - these are most likely related to subwoofer placement (my guess would be SBIR from opposite walls and ceiling), but given the size of the room I'm not sure if this can be improved much through placement.

If you'd like, you can try to tweak just a couple RoomFit parameters to see if that results in any improvement, e.g.:

WiiM Home App "Room Correction" menu settings:

• Max Gain = +12 dB
• Non-Boost Mode = Enabled
  • Note: this is a newer parameter in RoomFit.

(Everything else should stay the same as before.)

If that doesn't help, you could probably get a a flatter result with EQs created in REW and then values configured manually in RoomFit.

On the other hand, if you are already satisfied there's of course no need to change anything!

 

[Andrew78]

Good to hear you are happy with your system! Investment in a measurement mic is IMHO a very good one.

Regarding your response, there are still some pretty severe response dips at 30Hz and about 43Hz - these are most likely related to subwoofer placement (my guess would be SBIR from opposite walls and ceiling), but given the size of the room I'm not sure if this can be improved much through placement.

If you'd like, you can try to tweak just a couple RoomFit parameters to see if that results in any improvement, e.g.:

"Room Correction" menu settings:

• Max Gain = +12 dB
• Non-Boost Mode = Enabled
  • Note: this is a newer parameter in RoomFit.

(Everything else should stay the same as before.)

If that doesn't help, you could probably get a a flatter result with EQs created in REW and then values configured manually in RoomFit.

On the other hand, if you are already satisfied there's of course no need to change anything!

Hi Dominikz,

I ran the test again with the parameters you indicated.
Here are the results.
Maybe something in the bass has improved (specially at 30Hz) !

 

[dominikz]

Hi Dominikz,

I ran the test again with the parameters you indicated.
Here are the results.
Maybe something in the bass has improved (specially at 30Hz) !

View attachment 28112

View attachment 28114

Hm, the 30Hz and 43Hz dips seem to be less severe (even before correction) in this last attempt. Do these dips look different if you measure at different locations in the room?

To test you can just use the new "Evaluate" function, which you can access if you tap on the edit icon on your active RoomFit profile:

 

[Andrew78]

Hm, the 30Hz and 43Hz dips seem to be less severe (even before correction) in this last attempt. Do these dips look different if you measure at different locations in the room?

To test you can just use the new "Evaluate" function, which you can access if you tap on the edit icon on your active RoomFit profile:
View attachment 28117

Yes, doing the assessment test in different points of the room changes the values.
Below are the results:

1) Central listening point (with which I did the previous calibration)


2) Left listening point relative to the center point (closest to the sub and approximately 1 meter away from the center point)

3) Listening point to the right of the center point (just over 1 meter away from the center point)

 

[dominikz]

Yes, doing the assessment test in different points of the room changes the values.
Below are the results:

1) Central listening point (with which I did the previous calibration)
View attachment 28118

2) Left listening point relative to the center point (closest to the sub and approximately 1 meter away from the center point)
View attachment 28119
3) Listening point to the right of the center point (just over 1 meter away from the center point)
View attachment 28120

OK, now we have something!

First, note that the vertical axis scale changes between the three evaluation attempts, so visually some aspects of the measurements seem more different then they really are.

With that in mind, we see that the 30Hz dip exists only at your main listening location and is gone if you move left or right.
That means the 30Hz dip is related to your main listening position, which we call LBIR (listener-boundary intereference response). Therefore moving the sub around won't help resolve this one, it can only be resolved by moving the listening position somewhere else.
As you can see, even relatively small changes in listening position may have a big impact on the response.

The ~43Hz dip is however consistent at all 3 positions and it is always 10-15dB deep (depending on your reference). So that one seems to be related to the specific sub position. But again, based on room dimensions that you shared previously I'm not sure that sub repositioning would help much - you can try a few alternative sub positions and use the Evaluate function to see if there's any improvement.

 

[Andrew78]

OK, now we have something!

First, note that the vertical axis scale changes between the three evaluation attempts, so visually some aspects of the measurements seem more different then they really are.

With that in mind, we see that the 30Hz dip exists only at your main listening location and is gone if you move left or right.
That means the 30Hz dip is related to your main listening position, which we call LBIR (listener-boundary intereference response). Therefore moving the sub around won't help resolve this one, it can only be resolved by moving the listening position somewhere else.
As you can see, even relatively small changes in listening position may have a big impact on the response.

The ~43Hz dip is however consistent at all 3 positions and it is always 10-15dB deep (depending on your reference). So that one seems to be related to the specific sub position. But again, based on room dimensions that you shared previously I'm not sure that sub repositioning would help much - you can try a few alternative sub positions and use the Evaluate function to see if there's any improvement.

Thank you for your feedback
I don't plan on changing the subwoofer's position (except closer or further from the rear wall) because, in my opinion, that's the only correct position in the room. I don't know where else to place it
Using the new microphone, however, has allowed me to calibrate the room better than before, and for me, that's already an excellent result!
To my ears, the system sounds good. By maintaining this room-fit calibration and playing with the different preset EQ parameters, I should be in an optimal situation.

 

[dominikz]

To my ears, the system sounds good.

And that is absolutely the most important thing! Enjoy!

 

[Andrew78]

And that is absolutely the most important thing! Enjoy!

Sorry to bother you again
I did a final test by working on the sub's app, adjusting the equalization and trying to fix the 45Hz drop.
Here are the latest results. I think there's been a slight improvement.
What do you think?