Room measurement, if someone could review and advise please.

[UpTheSwanny]

I'd swap speakers left to right and right to left and then remeasure to see how much the speakers deviate from each other.

Great point. I was worried for a moment as I thought it could be the speakers. But the picture is the same with the speakers swapped over. Thank you.

 

[ozzy9832001]

For such a small room, the measurements aren't really that bad at all. There are some differences between the 2 speakers.

For those that don't want to download the .mdat. Brown is right, blue is red and purple is the avg of both.

It looks like you have a lot of cancellations happening in from about 800hz all the way down to 100hz. A lot of this I'm willing to bet is SBIR. The low mids are probably off the back wall and side walls.

Am I correct in assuming you have a roughly 8' ceiling height? That would explain the massive peak at about 140hz.

In order to make a dent in this, you'd probably need significant large, thick panels. They should have a limiter in place to prevent absorption above say 500hz.

Even if the speakers are symmetrical and equal distance from the SWs, you can still easily get variations between the 2 speakers. One could be an external wall and the other a partition. What's on the other side of the sheetrock could matter too. Windows? Doors? all add to the equation. Most rooms aren't completely square either. My room has a 3/4" deviation, so I have to factor that in when placing the speakers.

 

[UpTheSwanny]

For such a small room, the measurements aren't really that bad at all. There are some differences between the 2 speakers. View attachment 310659

For those that don't want to download the .mdat. Brown is right, blue is red and purple is the avg of both.

It looks like you have a lot of cancellations happening in from about 800hz all the way down to 100hz. A lot of this I'm willing to bet is SBIR. The low mids are probably off the back wall and side walls.

Am I correct in assuming you have a roughly 8' ceiling height? That would explain the massive peak at about 140hz.

In order to make a dent in this, you'd probably need significant large, thick panels. They should have a limiter in place to prevent absorption above say 500hz.

Even if the speakers are symmetrical and equal distance from the SWs, you can still easily get variations between the 2 speakers. One could be an external wall and the other a partition. What's on the other side of the sheetrock could matter too. Windows? Doors? all add to the equation. Most rooms aren't completely square either. My room has a 3/4" deviation, so I have to factor that in when placing the speakers.

Thanks for that.

 

[olieb]

I hope some will come back and see the new images and make comment if appropriate.

As these are new measurements they show the effect of (supposedly) small changes in position on FR (in bass+mid).
While quite similar for the most part there are distinct differences around 800 Hz as @ozzy9832001 already mentioned (SBIR?). And the null at 115 Hz is quite dependent on position too.

With the information at hand I tried a "best guess" and arrived at this for the right speaker.

Comparison to the measurement up to 300 Hz.

For a better match it would be helpful to have the dimensions of the room and the positions of mic and speakers. And one would still have to guess absorption of the walls. Do you have brick walls or dry walls?
The way it looks the null at 115 Hz results from the speaker position does not couple to the room modes with that frequency. That might be the case if the speaker (or the listening) position is at 1/4 of room size (length and width). Small changes of positioning then make a big difference. (See left speaker FR).
REW room sim is quite a good tool for this, you might try.

 

[ozzy9832001]

This is your summation on a 50dB scale @ VAR smoothing. Gives more insight into the areas where it's really needed. I feel like currently, the speakers should sound fairly bright. From 1K and up things look OK except the minor dip at 3k. Everything below 1k is lacking energy in comparison because of cancellations.

Your huge dip at 105-110 is your length room mode. That correlates to your 10' dimension.

If you have the speakers against the wall as close as they can get then the dip in the 300's is probably SBIR. However, it could be the 6' dimension as well. You somewhat have a peak at about 180hz and then the dip at 360hz could be explained by that as well. Hard to tell.

Peak at 140 is from your ceiling height.

Any chance we could get a little diagram of your room and you can draw in where the speakers are and where the MLP is?

 

[UpTheSwanny]

As these are new measurements they show the effect of (supposedly) small changes in position on FR (in bass+mid).
While quite similar for the most part there are distinct differences around 800 Hz as @ozzy9832001 already mentioned (SBIR?). And the null at 115 Hz is quite dependent on position too.
View attachment 310732
With the information at hand I tried a "best guess" and arrived at this for the right speaker.
View attachment 310734
Comparison to the measurement up to 300 Hz.
View attachment 310735
For a better match it would be helpful to have the dimensions of the room and the positions of mic and speakers. And one would still have to guess absorption of the walls. Do you have brick walls or dry walls?
The way it looks the null at 115 Hz results from the speaker position does not couple to the room modes with that frequency. That might be the case if the speaker (or the listening) position is at 1/4 of room size (length and width). Small changes of positioning then make a big difference. (See left speaker FR).
REW room sim is quite a good tool for this, you might try.

Hey, thanks so much for that. I used the room sim and have adjusted my room. Took some doing.

I have set the tome dip switches to flat. I had adjusted them for corner/wall placement. The difference is enormous. I wonder if number 1 dip should be on for nearfield?

Here are the charts:

Left speaker.

Right speaker.

Right and Left

I used the room sim.

Here are the meat files:
left: https://www.dropbox.com/scl/fi/oc7e...eft.mdat?rlkey=cam1w3qlz5yppsd8uzklbmnkq&dl=0
Right: https://www.dropbox.com/scl/fi/tg05...ght.mdat?rlkey=hh3hws16ayu5tcr5q5dxkt7g6&dl=0
left and right: https://www.dropbox.com/scl/fi/21d7...ght.mdat?rlkey=crk7yc3cc2obnbwru8nwdb3do&dl=0

I can't believe the difference. I haven't had time to sort out the best position for the first reflection diffuser yet, they're in approximate positions at the moment.
To my untrained eye, right and left graphs now look more similar. The separation, bass and stereo image are all improve and the clarity is amazing. Just listening to the Bless the Weather album, John Martyn. Wow.

Thanks again everyone.

 

[UpTheSwanny]

View attachment 310851
This is your summation on a 50dB scale @ VAR smoothing. Gives more insight into the areas where it's really needed. I feel like currently, the speakers should sound fairly bright. From 1K and up things look OK except the minor dip at 3k. Everything below 1k is lacking energy in comparison because of cancellations.

Your huge dip at 105-110 is your length room mode. That correlates to your 10' dimension.

If you have the speakers against the wall as close as they can get then the dip in the 300's is probably SBIR. However, it could be the 6' dimension as well. You somewhat have a peak at about 180hz and then the dip at 360hz could be explained by that as well. Hard to tell.

Peak at 140 is from your ceiling height.

Any chance we could get a little diagram of your room and you can draw in where the speakers are and where the MLP is?

Thanks for that. In my previous post there is a shot of the room sim. to give dimensions. I have a window in the front wall behind the speakers and there is the door on the left wall at the rear. I can sketch them in later if necessary.