Wiim Roomfit questions, please help

[Emiyanez]

Great post!

You're slowly getting there! My two cents... I think that the gain on the sub is still too high so you are over-correcting the signal while you could still lower the sub volume. Ideally, your RAW curve (grey) should overlap as much as possible with the target (green) before you apply the room correction. As @harkpabst suggested, it should be slightly above it in the bass region cause this will help with the correction.

SBIR may be tricky to correct. I also suffer from it in my room with my speakers and speaker placement did not solve it. In your case, frequency is low enough that you can partially compensate by crossing at a higher frequency and applying some EQ. As suggested, try to place the sub centered between the speakers so it's harder for your brain to locate it.

I am not sure about the size of your room but sometimes bigger is not better. It's true that small subs (8 inches) do not have the authority and dynamics of the bigger ones. However, big subs could be an overkill and harder to integrate in certain small rooms.

 

[DanielT]

The one thing that stands otu is the small but deep dip slightly above 100 Hz. This dip remains the same, no matter if you're using the swept sine measurement or the moving microphone method. If the dip remains even with the spatial averaging of the MMM, this is strong evident for the dip not being cause by room modes!

The most likely reasons are either inverted polarity between main speakers and sub (this could be fixed using the phase switch in the WiiM Home app) or by SBIR (speaker boundary interference response). My personal guess is SBIR. If there was a polarity Inversion I would expect the dip to be right at the crossover frequency between sun and mains. However, the acoustical crossover frequency could differ somewhat from the electrical crossover frequency set in the WHA.

There's one easy way of testing this: Set the phase switch in the WiiM's sub management to 180⁰ and repeat the RoomFit run (with all other settings being the same as before).
If the dip goes away or becomes less pronounced, this is it.
If the dip stays the same, becomes more pronounced, moves or a second dip shows up, the the phase setting of 0⁰ was correct and the dip is caused by SBIR, indeed.

That might be worth a try, but tkdj123 has disabled the phase control and low-pass filter on the subwoofer and is letting the WiiM handle all bass management—with the phase set to 0 (see post #29)—and considering the physical placement of the sub and speakers relative to the listening chair:

It probably shouldn't cause any issues, but one can always try flipping the phase and running a few sweeps, as you suggested. It only takes a couple of minutes.

My suggestion regarding corner placement—or any other position—was mostly just in case tkdj123 might find it fun to experiment. Since the WiiM allows you to save multiple EQ settings, he wouldn't have to start from scratch if he moved the subwoofer back to its original position later on.

Regarding speaker placement in general, here are some tips and recommendations from Genelec (you’re likely familiar with this info, but it might be useful for tkdj123):

How to place your monitors? - Genelec.com

To create the ideal listening experience, several aspects need to be taken into account when placing the monitors within the listening space. First, you need to identify the listening area within the space and consider where the listener will be placed in relation to the space as well as the...

www.genelec.com

 

[harkpabst]

That might be worth a try, but tkdj123 has disabled the phase control and low-pass filter on the subwoofer and is letting the WiiM handle all bass management—with the phase set to 0 (see post #29)—and considering the physical placement of the sub and speakers relative to the listening chair:

It probably shouldn't cause any issues, but one can always try flipping the phase and running a few sweeps, as you suggested. It only takes a couple of minutes.

Yes, and I strongly advise leaving the subwoofer's physical settings at "neutral" positions and making all the changes from within the WiiM Home app.

The thing with "phase" (which should really be labelled "polarity", but nobody does is) is this: You never know if either the amp or the subwoofer has inverted polarity or not. It happens all the time with all kinds of equipment. If so, then even a setup with all speakers placed at the same distance from the MLP can suffer from cancellation. Also, the acoustical center of e.g. the tweeter can be quite different from that of the subwoofer. We don't have to discuss the delay introduced by DSPs in subwoofers, because the Speedwoofer doesn't have one, luckily.

Regarding speaker placement in general, here are some tips and recommendations from Genelec (you’re likely familiar with this info, but it might be useful for tkdj123):

One of the best sources regarding this topic, indeed.

 

[harkpabst]

I think that the gain on the sub is still too high so you are over-correcting the signal while you could still lower the sub volume. Ideally, your RAW curve (grey) should overlap as much as possible with the target (green) before you apply the room correction.

Couldn't agree more.

SBIR may be tricky to correct. I also suffer from it in my room with my speakers and speaker placement did not solve it. In your case, frequency is low enough that you can partially compensate by crossing at a higher frequency and applying some EQ. As suggested, try to place the sub centered between the speakers so it's harder for your brain to locate it.

Yes, this can be hard to impossible to resolve. Placing the speakers as close as possible - as outlined e.g. by Genelec - is your best bet, but might not solve the issue entirely.

Room dimensions were mentioned in the OP. A relatively small space.

 

[DanielT]

The thing with "phase" (which should really be labelled "polarity", but nobody does is) is this: You never know if either the amp or the subwoofer has inverted polarity or not. It happens all the time with all kinds of equipment. If so, then even a setup with all speakers placed at the same distance from the MLP can suffer from cancellation. Also, the acoustical center of e.g. the tweeter can be quite different from that of the subwoofer. We don't have to discuss the delay introduced by DSPs in subwoofers, because the Speedwoofer doesn't have one, luckily.



One of the best sources regarding this topic, indeed.

You have a point there. You might think you're doing things right, but sometimes it’s good to have it pointed out that things might be a bit off, like...:

Spoiler

 

[tkdj123]

I think you're really making great progress here!

Some general comments for a start. @RandomEar has published a quick guide (plus references) for using MMM here:

The moving microphone method (MMM) for Dummies using REW

After getting a couple of weird results on my first MMM measurements, I went searching around the forums & YouTube for what went wrong. To save others from gathering various bits and pieces of info from a dozen sources, I decided to publish this quick write-up here. You can use it as a rough...

www.audiosciencereview.com

It's mainly written with REW in mind but the basics apply, no matter which tool you use. My very short summary: a) Don't move the mic/phone too fast and cover the area around your main listening position with your movement. An arm's length distance is certainly enough, your room isn't that big anyway. b) Make sure to use an appropriately high level when using MMM, because MMM is much more prone to disturbances by external noise. I'd probably use a volume setting of at least 35 or 40 on the WiiM Amp. Your measurements do look good and consistent, though.

Now on to your measurements. Did you notice the graph legends?
View attachment 562448
The "Results Overview" shows the target curve, the measurement before correction, the actual equalisation applied (this is the same as the graph you find in the RoomFit profile, just in a slightly different presentation) and the estimated response after correction.

View attachment 562449
The "Final Assessment" shows the target curve (same as above), the measurement before correction (same as above) and the frequency response that was actually measured after applying the EQ.

The important bit here is that the estimated curve and the measured curve match almost perfectly! This proves that your measurements are reliable and if high quality.

The one thing that stands otu is the small but deep dip slightly above 100 Hz. This dip remains the same, no matter if you're using the swept sine measurement or the moving microphone method. If the dip remains even with the spatial averaging of the MMM, this is strong evident for the dip not being cause by room modes!

The most likely reasons are either inverted polarity between main speakers and sub (this could be fixed using the phase switch in the WiiM Home app) or by SBIR (speaker boundary interference response). My personal guess is SBIR. If there was a polarity Inversion I would expect the dip to be right at the crossover frequency between sun and mains. However, the acoustical crossover frequency could differ somewhat from the electrical crossover frequency set in the WHA.

There's one easy way of testing this: Set the phase switch in the WiiM's sub management to 180⁰ and repeat the RoomFit run (with all other settings being the same as before).
If the dip goes away or becomes less pronounced, this is it.
If the dip stays the same, becomes more pronounced, moves or a second dip shows up, the the phase setting of 0⁰ was correct and the dip is caused by SBIR, indeed.

Fighting SBIR is less trivial. You basically have two options: a) Move the main speakers further away from all walls. It looks to me like your option are limited in your room concerning this approach. b) Move the speakers (and sub) as close as possibe to the front wall (but still as far as possible from the side walls) and increase the crossover frequency to 100 Hz or even 110-120 Hz.

The latter might sound counterintuitive, but it's really purely science based. With a crossover frequency above 80 Hz you should not try corner placement, though. Keep the sub rather symmetrically between the speakers, but also as.clise.to the front wall as possible.

Breakfast time for me. You've got some more things to try.

Here is re-run room fit using the harman curve with sub phase at 180. Still have the dip, and it looks like there is even a second dip.

So I moved the speakers closer togethor, further from the side walls (see pic) and here is the new harman curve with sub phase at 0 degrees.

As you can see there is a significant dip at 100hz. So what do I do? Do I just keep moving the speakers closer togethor and tinkering with there placement until the dip goes away?




@Emiyanez

​

 

[Bleib]

A tip. Buy a thick carpet.

 

[Emiyanez]

You did a pretty good job. I have a couple of quick questions though. At which frequency have you set the crossover in the measurements you are showing? Try to set it at 120Hz to see how it looks. Have you played with the phase of the sub from the Wiim app to make sure that the deep at 100Hz is not due to interference between the sub and the speakers? How does the deep look if you deactivate the sub from the WiiM app and do some measurements only with the speakers?

Something else you could try, although it's not really orthodox, is crossing the sub rather high (120Hz) and letting the speakers play full range. Both the speakers and the sub would overlap in the 100Hz region. This may make things worse but it takes you 5 min to try.

I honestly think none of the above will completely solve the problem as it seems to be an interference of your system with your room. As suggested, a thick carpet may help with floor reflections. Playing with the distance to the front wall and the relative distance of the sub and the speakers may also help. I would try to minimize the deep as much as possible playing with the above options and, maybe, apply son boost around 100Hz once the deep is much less pronounced. I had a similar problem with a deep at 200Hz and combination of placement with a bit of EQ made it much better

 

[DanielT]

Here is re-run room fit using the harman curve with sub phase at 180. Still have the dip, and it looks like there is even a second dip.

View attachment 562559View attachment 562561



So I moved the speakers closer togethor, further from the side walls (see pic) and here is the new harman curve with sub phase at 0 degrees.

View attachment 562562View attachment 562563



As you can see there is a significant dip at 100hz. So what do I do? Do I just keep moving the speakers closer togethor and tinkering with there placement until the dip goes away?




@Emiyanez

​

So, you had the right setting in the WiiM’s bass management (the 0-degree phase setting), because your measurement now shows what happens with the 180-degree setting—it made things worse. That leaves what @harkpabst mentioned regarding SBIR:

Check this out:

How to place your monitors? - Genelec.com

To create the ideal listening experience, several aspects need to be taken into account when placing the monitors within the listening space. First, you need to identify the listening area within the space and consider where the listener will be placed in relation to the space as well as the...

www.genelec.com

After that, switch back to the 0-degree phase setting. But first, measure the subwoofer and the speakers individually (at this stage, the polarity/phase relationship between them doesn't matter, since there is no interaction between them, so to speak).

Place the speakers right against the back wall, disconnect the subwoofer, and run them full-range.
Do the same with the subwoofer. Low-pass crossover filter set to 200 Hz or completely bypassed; the interesting part is the dip around 100 Hz—don't worry about how it looks above that: place the sub against the back wall or in a corner, disconnect the speakers, and measure. You can proceed once you have those results. That’s how I would do it, at least.

What does your listening room look like? I mean the dimensions. Could you sketch it out and post it in the thread?

Let me throw this out there: it could be your mobile phone's microphone struggling to handle low frequencies, resulting in what you're seeing. Maybe... though I should add I'm not certain about that hypothesis. Could you take measurements with your tablet (if you have one) and compare?
Or order a UMIK-1 or UMIK-2. You might want to hold off on further testing and measurements until your measurement microphone arrives. It could be worth the ~$130 (for the UMIK-1) just for peace of mind, so to speak.

 

[harkpabst]

Here is re-run room fit using the harman curve with sub phase at 180. Still have the dip, and it looks like there is even a second dip.

Well done, great result, this is exactly what we wanted to see!

The new dip is pretty much exactly at 80 Hz and it's caused by the 180⁰ phase setting. Your correct conclusion was that the 0⁰ phase setting is needed for the constructive addition of the speakers' and the subwoofer's output.

Changing one parameter at a time is usually the best way to target such issues (with few exceptions).

SBIR (= impact of wall reflections) can be caused by all boundaries (= walls) but it's the wall right behind the speakers that usually has the biggest impact. In your room, the distance to the side walls is also limited, but - as mentioned by @DanielT - moving your speaker closer to the wall behind them is your best bet. The closer the speaker is to the wall, the higher the frequency of the first cancellation due to wall reflections. The idea is to shift this cancellation point to a frequency so high that the speaker no longer radiates equally into all directions, but predominantly radiates towards your listening position. Even just reducing the level of reflected sound will lower the cancellation, thus reducing the depth of the dip.

Don't believe in the old audiophile myth telling you that speakers must be placed far from any walls. This advice isn't wrong per se. But a) you don't have the space to place each speaker 1,5 m or more from any wall. And b) you don't need to fear boomy or overwhelming bass because of the close by wall. RoomFit will tame this for you.

The second approach (which can be used in combination) is to increase the crossover frequency to the subwoofer, as already mentioned by @Emiyanez. Don't shy away from 120 or 125 Hz, if it helps getting rid of the dip. Again, the sun should be placed as close to the wall as possible and the distance to the left and right speaker should be as equal as possible.

Personally, I'm not a big fan of the "main speakers output bass" setting. Yes, this setting can potentially be helpful to pressurize the room more evenly, thus reducing the excitation of standing waves. It does not fight SBIR directly, quite the contrary. Most importantly, you give up one of the biggest benefits with small speakers and subwoofers: With a high pass filter in place, the small mid-woofers are released from most of the large cone excursion and thermal stress caused by deep bass. The result is less distortion. Less harmonic distortion, less IM distortion, less Doppler distortion, less linear distortion caused by an overheating voice coil.

Do I just keep moving the speakers closer togethor and tinkering with there placement until the dip goes away?

Generally yes, but it's not moving the speakers closer to each other, it's moving them closer to the wall behind them that has the biggest potential for improvement. And don't forget moving the sub back as much as possible, too.

A thick carpet is generally a good idea but will have almost no effect in the frequency range we're currently dealing with. It might still bring a noticeable improvement, but in other areas.

There is one mor option that we can try and that's independent left and right RoomFit correction instead of combined stereo correction. but looking at your fairly symmetrical room I think that the changes mentioned above are.mkre important, so I'd rather leave this for later.

Whenever you reposition your speakers and sub you need to re-run RoomFit,.of course, but I guess that's no news for you. You might also want to re-run WiiM's subwoofer calibration, but if it increases the subwoofer level again, don't follow this route. The current subwoofer level looks perfectly right for me.

Let me throw this out there: it could be your mobile phone's microphone struggling to handle low frequencies, resulting in what you're seeing. Maybe... though I should add I'm not certain about that hypothesis. Could you take measurements with your tablet (if you have one) and compare?
Or order a UMIK-1 or UMIK-2. You might want to hold off on further testing and measurements until your measurement microphone arrives. It could be worth the ~$130 (for the UMIK-1) just for peace of mind, so to speak.

Being able to perform additional measurements with a quality mic like the UMIK-1 would be perfect, of course.

Still, I don't think that the iPhone 15 built-in microphone is the root cause here. Also, independent measurements of the subwoofers and mains would certainly create more insight. They are a bit cumbersome to do, though, and just using RoomFit as a tool, the results will look a little confusing at a first glance.

If @tkdj123 is prepared for some extra hassle, the it's all well. If not, I think that just moving sub and speakers close to the wall as step 1 and the increasing the crossover frequency to ~120 Hz as step 2 will also clearly show if there is progress or not.

 

[Ruediger]

I think mains playing bass can never be good with bookshelf size speakers. It takes away the largest plus (speakers having room to do what they do best, which is not bass) and fills the room with a rather undefined and cloudy bass.

 

[DanielT]

I think mains playing bass can never be good with bookshelf size speakers. It takes away the largest plus (speakers having room to do what they do best, which is not bass) and fills the room with a rather undefined and cloudy bass.

Full-range—but only during a test period. After that, paired with a subwoofer.

tkdj123 is currently troubleshooting, so it’s a matter of taking it step by step and experimenting. You have to measure various things—specifically, different placement options for the speakers and the subwoofer.
That isn't physically difficult, since neither the sub nor the speakers are too heavy to move around.

By the way, @tkdj123 are the speakers playing in phase with each other? No issues with reversed polarity there?

 

[tkdj123]

You did a pretty good job. I have a couple of quick questions though. At which frequency have you set the crossover in the measurements you are showing? Try to set it at 120Hz to see how it looks. Have you played with the phase of the sub from the Wiim app to make sure that the deep at 100Hz is not due to interference between the sub and the speakers? How does the deep look if you deactivate the sub from the WiiM app and do some measurements only with the speakers?

Something else you could try, although it's not really orthodox, is crossing the sub rather high (120Hz) and letting the speakers play full range. Both the speakers and the sub would overlap in the 100Hz region. This may make things worse but it takes you 5 min to try.

I honestly think none of the above will completely solve the problem as it seems to be an interference of your system with your room. As suggested, a thick carpet may help with floor reflections. Playing with the distance to the front wall and the relative distance of the sub and the speakers may also help. I would try to minimize the deep as much as possible playing with the above options and, maybe, apply son boost around 100Hz once the deep is much less pronounced. I had a similar problem with a deep at 200Hz and combination of placement with a bit of EQ made it much better

Thank you! Appreciate your input.

The crossover is set to 80Hz. I have played with the phase and 0 degrees is the correct phase.I haven't tried crossing the sub at a higher frequency and so I will give that a shot.

I think one thing to note though is there is toe in on the speaker placement so that back of the speakers are actually pointed towards the corner of the walls and sides; I don't know if this makes a difference? (see the pics of placement attatched)

 

[tkdj123]

So, you had the right setting in the WiiM’s bass management (the 0-degree phase setting), because your measurement now shows what happens with the 180-degree setting—it made things worse. That leaves what @harkpabst mentioned regarding SBIR:

Check this out:
View attachment 562623

How to place your monitors? - Genelec.com

To create the ideal listening experience, several aspects need to be taken into account when placing the monitors within the listening space. First, you need to identify the listening area within the space and consider where the listener will be placed in relation to the space as well as the...

www.genelec.com

After that, switch back to the 0-degree phase setting. But first, measure the subwoofer and the speakers individually (at this stage, the polarity/phase relationship between them doesn't matter, since there is no interaction between them, so to speak).

Place the speakers right against the back wall, disconnect the subwoofer, and run them full-range.
Do the same with the subwoofer. Low-pass crossover filter set to 200 Hz or completely bypassed; the interesting part is the dip around 100 Hz—don't worry about how it looks above that: place the sub against the back wall or in a corner, disconnect the speakers, and measure. You can proceed once you have those results. That’s how I would do it, at least.

What does your listening room look like? I mean the dimensions. Could you sketch it out and post it in the thread?

Let me throw this out there: it could be your mobile phone's microphone struggling to handle low frequencies, resulting in what you're seeing. Maybe... though I should add I'm not certain about that hypothesis. Could you take measurements with your tablet (if you have one) and compare?
Or order a UMIK-1 or UMIK-2. You might want to hold off on further testing and measurements until your measurement microphone arrives. It could be worth the ~$130 (for the UMIK-1) just for peace of mind, so to speak.

I think one thing to note though is there is toe in on the speaker placement so that back of the speakers are actually pointed towards the corner of the walls and sides; I don't know if this makes a difference? (see the pics of placement attatched)

If I keep the toe in I can't place them right against the back wall because they are at an angle and so part of the back of the speakers are actually facing towards the corner of the wall and side wall. To place them directly against the back wall would mean I have to eliminate all toe in.

 

[harkpabst]

I think one thing to note though is there is toe in on the speaker placement so that back of the speakers are actually pointed towards the corner of the walls and sides; I don't know if this makes a difference? (see the pics of placement attatched)

I cannot speak for anybody else,.but I for one read all replies, not just the ones directed at me. So as far as I am concerned you don't have to repeat statements multiple times. Saves you some time and efforts.

Looking at the spinorama.org data for the ES 20 I think that there's no real need to toe them in. Getting them closer to the wall would be my personal preference.

The ES 20.is a ported design but the "Power Port" is redirecting the sound from the port anyway and because big the subwoofer integration there will be hardly any output from the port at all.

If you ask me, have them pointing straight but bring them back all the way and increase the subwoofer crossover frequency.

 

[tkdj123]

I cannot speak for anybody else,.but I for one read all replies, not just the ones directed at me. So as far as I am concerned you don't have to repeat statements multiple times. Saves you some time and efforts.

Looking at the spinorama.org data for the ES 20 I think that there's no real need to toe them in. Getting them closer to the wall would be my personal preference.

The ES 20.is a ported design but the "Power Port" is redirecting the sound from the port anyway and because big the subwoofer integration there will be hardly any output from the port at all.

If you ask me, have them pointing straight but bring them back all the way and increase the subwoofer crossover frequency.

So I followed your advice

1. I first moved the speakers closer togethor and as close to the backwall as well as moved the sub closer to the back wall. (see the pic for speaker placement), set the crossover frequency to 120, and re-ran room fit (without MMM).

2. I then removed the table, moved the speakers even closer togethor, keeping crossover at 120 and reran roomfit (without MMM).

There is definetly an improvement, the dip at 100hz is not as prounounced.


3. I moved the speakers as close togethor as I could and as close to the backwall as I could, keeping crossover at 120hz. And re-ran roomfit (without MMM).

Looks even better to me. So I ran it now with MMM, keeping all settings the same. This is the Harman curve.

This is the BK Curve

My final roomfit settings are below:

My sub settings:

Overall there is a noticeable improvement in the final room correction graph, is there anything else I can do?


@Ruediger

@DanielT

@Emiyanez

 

[john61ct]

Howzit SOUND to you?

In the end, more important than looking at the lines

 

[tkdj123]

Howzit SOUND to you?

In the end, more important than looking at the lines

I would say it does sound better although I do miss the wider stage I get when the speakers were further apart and toe in (although this could be my ears not being used to the difference) it sounds better and I am happy that I got as close to optimized as I could using the iphone speaker.

Appreciate everyone's input and help!

 

[Ruediger]

Try a rectangle out of sofa and speakers. Probably put them in/near the corner I guess. Do not toe them in. And the subwoofer exactly in the middle.

 

[tkdj123]

Try a rectangle out of sofa and speakers. Probably put them in/near the corner I guess. Do not toe them in. And the subwoofer exactly in the middle.

Thanks!

I tried that and moved them further apart by around 3.5 feet like you said

The dip at 100hz returns again to nearly -20 although the rest of the graph looks pretty accurate, so clearly moving them closer togethor removes the dip.

I am going to keep it as closer togethor as possible because I don't think the wide sound stage is worth it compared to the overall quality.


Thanks again everyone for your help!