RoomFit Moving Mic Measurement (beta) - improvements

[dominikz]

Today I accidentally noticed several improvements to RoomFit Moving Mic Measurement (MMM) beta feature which seem to have been added silently at some point:

• There's a screen now explaining how to perform MMM
  
• It is now possible to use "Individual Channel RoomFit" mode while MMM is enabled:
  
• If MMM is enabled only periodic pink noise is used to measure the response, while previously there was first a sweep and then periodic pink noise. This is a major improvement because previously sweep response was given significantly higher weight (link), decreasing the benefits of MMM.
• If MMM is enabled periodic pink noise and MMM is also used during result evaluation!

Let me try to illustrate the benefits, here's the same system measured with a single sweep vs MMM (periodic pink noise):


Both responses are quite similar below 100Hz (meaning you can use either for bass response correction), but they start to diverge above that - with MMM looking much smoother, while sweep gives an irregular/noisy response at higher freqencies.
This is because the spatial averaging of the MMM filters-out audibly benign room reflections, and gives a response that is closer to anechoic predicted in-room response. This makes MMM responses a slightly better representation of loudspeaker tonality that we actually hear.

There is one potential problem, though - in my tests when MMM was enabled, RoomFit didn't apply any correction below 30Hh, even when lower bound of the correction range was set to 20Hz. Not sure if this is intentional (i.e. due to greater sensitivity of MMM to ambient noise compared to a sweep), or if it is a bug.

All in all great work @WiiM Team @WiiM Support @jiaxin.li (WiiM) @RyanWithWiiM, thanks!

 

[Wiimer]

Hi @dominikz

I found it when WiiM Home App v3.4.3 arrived, so MMM seems to have been upgraded before that. I really like it.

When I turn MMM on before evaluation, I can use pink noise for the evaluate. (I don't remember if this was possible before.)

However, the issue where EQ turns off when evaluate is executed has not yet been fixed. The team seems to have determined that no revisions are necessary.

 

[dominikz]

When I turn MMM on before evaluation, I can use pink noise for the evaluate. (I don't remember if this was possible before.)

I think this is new, I seem to recall that originally sweep was always used for evaluation.

However, the issue where EQ turns off when evaluate is executed has not yet been fixed. The team seems to have determined that no revisions are necessary.

That’s too bad, having the ability to evaluate RoomFit and EQ together was really convenient! Did you get some official feedback from WiiM on this?

 

[Wiimer]

Did you get some official feedback from WiiM on this?

Unfortunately, no.

Since there was no response, I assumed they had decided to turn off the EQ.

 

[canard]

A Roomfit vs rew ( in "variable") ???
(I think it will be interesting in the future to compare them with those who can implement both approaches, mmm )
;-)

 

[FrankR]

Just wanted to express my gratitude to @dominikz and @Wiimer for all the knowledge you've passed on to some of us mere mortals. I greatly appreciate all that you contribute to this forum!

 

[MCG555]

Just wanted to express my gratitude to @dominikz and @Wiimer for all the knowledge you've passed on to some of us mere mortals. I greatly appreciate all that you contribute to this forum!

Totally agree!

 

[canard]

I think this is new, I seem to recall that originally sweep was always used for evaluation.

That’s too bad, having the ability to evaluate RoomFit and EQ together was really convenient! Did you get some official feedback from WiiM on this?

What type of straightening are you comparing sweep vs mmm? Sure that s the same in both cases in "traitement" ?
Just question ;-)
If the MMM mode becomes truly polished, that's great news because it will probably be the preferred alternative for the vast majority of Wiim users "not expert" ;-)

But the issue of gain/level management, and of signal processing, remains unresolved.

 

[dominikz]

Just wanted to express my gratitude to @dominikz and @Wiimer for all the knowledge you've passed on to some of us mere mortals. I greatly appreciate all that you contribute to this forum!

Totally agree!

That’s very kind of you to say! I'm really glad when people find some of these posts interesting!

What type of straightening are you comparing sweep vs mmm? Sure that s the same in both cases in "traitement" ?
Just question ;-)

1/12 smoothing in both cases.

If the MMM mode becomes truly polished, that's great news because it will probably be the preferred alternative for the vast majority of Wiim users "not expert" ;-)

It seems to me RoomFit MMM is pretty good already.

However single point sweep is much quicker, and since it gives very similar results to MMM at bass frequencies, in many cases it may still be a preferred choice.
Remember also that sweep is more resistant to ambient noise compared to MMM.

But I personally prefer MMM as it is easier to get repeatable results between runs, and the response looks closer to how the system sounds.

In any case, RoomFit is becoming a very powerful tool!

 

[canard]

The "mmm" is very popular and widely used in my country for a pleasing result....
;-)