Looking for help and insight regarding REW room measurements - what data would you want?

[levimax]

So, I am doing L and R moving mic measurements, and the right channel shows a pretty big dip at around 150 hz. I have turned my whole room upside down (almost literally) to see what might cause it, but I can't figure it out...

Here is the .mdat

I also used RTA for longer periods to check out what might be causing it - moving stuff/panels in real time - but I can't seem to find it at all. I also swapped the monitors to see if it might be a faulty monitor, but still got the exact same result, so it's not the monitor itself. Any ideas?

Should I be worried about that dip at around 150hz on the R channel? Am I overthinking it? It seems like a somewhat critical frequency range.

And what do you guys think of the dip between 200hz and 400hz?

This is when I'm looking at it at 1/48.

@Sokel @levimax @sam_adams @thcdru2k @DWPress @Keith_W

Thanks.

UPDATE:

I found a very thick pillow and placed it right above the right speaker in a horizontal position. The dip goes away by like 8db. Added .mdat for comparisons. Did extra double check comparisons to make sure it wasn't a coincidence.

Do you think the measurement with the pillow above the right speaker is better? Or am I still overthinking things?

Thanks again!

As mentioned a combined R+L would be helpful. Deep and narrow dips don't sound nearly as bad as they look, use Psychoacoustic smoothing to see what you would actually hear. I don't see anything unusual except for the flat to upward sloping FR. To me it seems like it would sound very bright. I usually don't like to EQ above Schroeder so I am not sure what to do about it. How far away from the speakers is the LP?

 

[janbth]

A couple of comments to those who take REW measurements and seek advice here on ASR:

• Always post a plot. mdats are fine, but some of us are on iPads or similar, and I’m not in general in a position to download, fire up REW, render a plot, etc. So mdats means nothing to me. Plots mean I can form an opinion and chime in.
• Always use Var smoothing. Do not use Psychoacoustic, 1/6, ERB, or anything else. The point is: smoothing in the bass hides data, where it it significant. Don’t do that. (Var smoothes in the upper frequencies, which is OK, because it hides comb filtering, which is not audible.)

 

[NathanW]

Once again: separate L & R sweeps and then one combined LR sweep. Use timing reference. There is no timing information in MMM measurements but give us a LR combined MMM. This is what a quick look in REW looks like with your recent MMM L&R but better information can be had if you provide what we ask for.

View attachment 538636

Hey, I hope I did what you asked for. Let me know otherwise. I'm honestely not trying to waste you guys' time.

 

[NathanW]

As mentioned a combined R+L would be helpful. Deep and narrow dips don't sound nearly as bad as they look, use Psychoacoustic smoothing to see what you would actually hear. I don't see anything unusual except for the flat to upward sloping FR. To me it seems like it would sound very bright. I usually don't like to EQ above Schroeder so I am not sure what to do about it. How far away from the speakers is the LP?

Thanks so much. I'm really learning more and more.

I replied to DWpress and added a new .mdat file with sweeps + timing reference, a combined sweep, and a combined MMM measurement.

You recommend checking everything on Psychoacoustic smoothing?

 

[levimax]

You recommend checking everything on Psychoacoustic smoothing?

Use Var smoothing for most things like creating corrections but to get a feel for how we actually hear things psychoacoustic is helpful and will put narrow dips into perspective.