What does this SPL/Waterfall graph suggest?

[uwekranz]

I've measured my 3mx5mx2,5m sized room using room eq wizard as a starting point to optimise acoustics for mixing purposes. Could you tell me what comes to your mind if you look at these measurements? What kind of first actions towards better room acoustics would you suggest in this case?

Would it help to use say 16 Auralex Bass Traps in the room?

The three lines in the SPL Graph are left, right and subwoofer respectively. The Waterfall graph belongs to the left speaker.

 

[MZKM]

What mic did you use? ThT high frequency drop off for your speakers is very odd.

The subwoofer doesn’t look too bad.

You’ll want to measure a full frequency sweep though, as the interaction of the subwoofer and speakers playing the same frequencies is what matters when optimizing for music playback; and since bass in music is almost always in stereo, you can have both the left & right playing for the measurement.

 

[uwekranz]

Thanks for the reply. I did use a beyerdynamic MM-1 as mic and also supplied the mic calibration file to the measurement software.

I added another measurement that was taken using a stereo signal through all three speakers at once.

What would be a posible way to to proceed from here?

 

[sigbergaudio]

The subwoofer seems to drop off very early, starting to roll off at 60hz.

The room seems to need general broad band dampening.

How does it sound?

 

[uwekranz]

Thanks for your reply. I have a dial called "Crossover" on my subwoofer and it was sitting at approximately 60hz. Now i opened it up to 250hz and did another measurement of the subwoofer only to compare the two settings.

General broad band dampening was suggested. Yes, i will try to achieve this using bass traps.

How does it sound. Well, i experimented with the digital room correction software "dirac live" and "sonarworks" which both took away a firm amount of bass. I prefered that less bassy land less boomy sound to some degree and also had a better impression of space and liked cymbal sounds better with digital room correction applied. Also the delay compensation feature of dirac live made a real difference to me. Those were the indications that made me think and feedback to a mix of mine i got as having too little bass. Then i thought let's do some physical adaptions to the room first and then have the digital correction work on top of it for the necessary corrections that remain.

 

[sigbergaudio]

The crossover controls how high the subwoofer goes, not how deep it goes. May I ask which subwoofer this is?

When it comes to building a mixing or mastering studio it's a pretty big and complex subject. There are Facebook groups and probably forums dedicated to the topic.

One example: https://www.facebook.com/groups/517162262483268/?ref=share

 

[uwekranz]

The subwoofer is called esi swk10.

And yes the crossover is a low pass filter. You did mean it should get lower. Now i see.

Thanks.

 

[ernestcarl]

Could you tell me what comes to your mind if you look at these measurements?

All it tells me is you have some prominent peaks and dips, but similar information is already found easily in REW's basic SPL & Phase window.

What kind of first actions towards better room acoustics would you suggest in this case?

It's always advisable to find the optimal placement of the speakers and least problematic seating/listening areas first to minimize SBIR and room mode problems.

Would it help to use say 16 Auralex Bass Traps in the room?

Probably, but depends what you're planning to "acoustically treat" since these velocity absorbing products aren't effective below maybe 100-80Hz.

Also, I'm guessing your sub level is too high in that first graph image, unless you are planning on widely overlapping the sub with the mains -- but that doesn't seem to be the case in your summed "all speakers" graph.

I say, it's a bit difficult to read your waterfall graphs because of the way it looks (primarily the scaling) -- time range should ideally be 400 ms or less.


Here are examples of mine which are somewhat easier to read:


WATERFALL

*no HPF means I've omitted a high-pass filter for the sub


DECAY

SPL & PHASE

I tend to break this rule, but when it comes to EQ, I'm convinced less is better in order to correct for the widest possible listening area -- after you've sorted out the other standing room acoustics issues first...

 

[uwekranz]

Wow, thanks for the input. I will think about these issues. That is the sub level compared to the level of the other speakers and overlay between sub and main speakers, the readability of the graphs, and speaker placement in gereral.

I'd like make some experiments and also look up some terms.

For now i can show you the spectograms of the room with and without some bass traps that i placed in the room. Have a look if you like.