Got my REW reverberation (RT60) graphs. Please comment!

[Snoochers]

I have a 25x16x9' home theatre used for movies and video games. I've finally gotten around to putting insulation on all walls/ceiling and took these measurements in REW with a umik-1 microphone. I don't trust my ear to tell what sounds good from what doesn't so I rely on objective data. I forget which REW values are important so I left all the lines in. My general Googling suggests that 200ms is on the "dead" end of good but I'm looking for any and all comments! Hopefully it is good enough and I can let it be but I can make changes if you see major issues.

I do recall seeing a few suggested RT60 curves but I can't find them. If you know of such curves given different room types I'd like to see them.

Is this bad, "ok", fine, good, amazing?

 

[Matias]

Looks pretty good to me. My room is a lot more challenging, believe me...

 

[ernestcarl]

I have a 25x16x9' home theatre used for movies and video games. I've finally gotten around to putting insulation on all walls/ceiling and took these measurements in REW with a umik-1 microphone. I don't trust my ear to tell what sounds good from what doesn't so I rely on objective data. I forget which REW values are important so I left all the lines in. My general Googling suggests that 200ms is on the "dead" end of good but I'm looking for any and all comments! Hopefully it is good enough and I can let it be but I can make changes if you see major issues.

I do recall seeing a few suggested RT60 curves but I can't find them. If you know of such curves given different room types I'd like to see them.


View attachment 219495View attachment 219496

Looks fine too me as well. Would be nice if you can post a spectral decay graph with a 20 ms rise time and 1/3 or 1/6 smoothing settings as well.

 

[Snoochers]

Looks fine too me as well. Would be nice if you can post a spectral decay graph with a 20 ms rise time and 1/3 or 1/6 smoothing settings as well.

Thanks do you mean this? This is under the tab called Decay. Not too used to REW sorry

 

[ernestcarl]

Thanks do you mean this? This is under the tab called Decay. Not too used to REW sorryView attachment 219498

The settings can be displayed and changed by clicking on the sprocket on the upper right hand side of the window.

Above spectral decay from a single summed IR example is somewhat much more exaggerated (from a somewhat very "dry" MCH setup) than what one would normally see elsewhere. It's only for one to see the overall "evenness" or balance of the full-range frequency magnitude and time response decay in the room.

 

[Snoochers]

The settings can be displayed and changed by clicking on the sprocket on the upper right hand side of the window.

View attachment 219500

Above spectral decay from a single summed IR example is somewhat much more exaggerated (from a somewhat very "dry" MCH setup) than what one would normally see elsewhere. It's only for one to see the overall "evenness" or balance of the full-range frequency magnitude and time response decay in the room.

Ok like this perhaps?

 

[ernestcarl]

Ok like this perhaps?View attachment 219501

Yep. That looks very good!

 

[Snoochers]

Yep. That looks very good!

Oh it does??? Lol. The one you showed was very flat so I thought perhaps that was what I was looking for.

 

[ernestcarl]

Oh it does??? Lol. The one you showed was very flat so I thought perhaps that was what I was looking for.

Other than the isolated peak in the bass around ~30 Hz, yep. Although, The late decay (beyond 20 ms) does not have to drop so fast to be "good" -- in fact, a little slower may be preferred by others in a pure stereo setup. But also don't forget to know what the settings and conditions are for what's being displayed: scaling, 1/3 smoothing etc... and it's also a pseudo-surround 4.1c "mch" summed response.

Here's from a single BM channel:

 

[ernestcarl]

Ok like this perhaps?View attachment 219501

The 350Hz dip and ~500 Hz peak in yours is likely contributed by boundary interference in the room and positioning. Equalizing these zones completely "flat" via DSP would not necessarily sound good elsewhere in the room.

 

[Ciobi69]

LLooks good to me,what did you use to treat all the lower frequency? Nice

 

[Snoochers]

LLooks good to me,what did you use to treat all the lower frequency? Nice

I have 30" deep base traps in the corners and the front wall is mostly 24" thick insulation

 

[alex-z]

Looks really good, decay times well balanced all the way from 60-10000Hz. Most people have a lot worse problems below 300Hz because their absorption panels are too thin.

Just need to use some EQ to fix up the bass response. Ideally you want 20-25Hz to be the highest point in your response, then gradually rolls off towards 200Hz. I personally run about a 1.5dB slope per octave (200Hz is 5dB below 20Hz), that is a matter of personal preference. Should only need 2-3 EQ filters for you to pull out that 70Hz bump, and create a nice slope.

 

[abdo123]

I have 30" deep base traps in the corners and the front wall is mostly 24" thick insulation

Impressive!

Did you make them yourself?

 

[Snoochers]

Looks really good, decay times well balanced all the way from 60-10000Hz. Most people have a lot worse problems below 300Hz because their absorption panels are too thin.

Just need to use some EQ to fix up the bass response. Ideally you want 20-25Hz to be the highest point in your response, then gradually rolls off towards 200Hz. I personally run about a 1.5dB slope per octave (200Hz is 5dB below 20Hz), that is a matter of personal preference. Should only need 2-3 EQ filters for you to pull out that 70Hz bump, and create a nice slope.

Oh I'm a bit confused sorry. Since these are reverb times, how does frequency response fit in? I did not include a standard SPL chart. Are you looking at the spectral decay or whatever it is called?

 

[Snoochers]

Impressive!

Did you make them yourself?

If by "made" you mean stacked hundreds of pounds of insulation then yes lol. I have panels on the walls but the front and back bass traps are literally just insulation leaning against the wall or floor.

 

[abdo123]

If by "made" you mean stacked hundreds of pounds of insulation then yes lol. I have panels on the walls but the front and back bass traps are literally just insulation leaning against the wall or floor.

I hope they're covered with at least some sort of fabric.

Usually when making a trap that thick you want to control the density of the material so that air can pass through to the other side successfully. Otherwise you're trap is not as effective below~80Hz or so.

It might be worth some investigating.

 

[Snoochers]

I hope they're covered with at least some sort of fabric.

Usually when making a trap that thick you want to control the density of the material so that air can pass through to the other side successfully. Otherwise you're trap is not as effective below~80Hz or so.

It might be worth some investigating.

Yes they're behind my screen and a false wall in the back. I read a lot about bass traps and such and I landed on the idea of having simply as much insulation as possible. Seemed to me that having an air gap is good of course but not as good as having simply more insulation. I could be wrong of course! No changing it now

 

[abdo123]

Yes they're behind my screen and a false wall in the back. I read a lot about bass traps and such and I landed on the idea of having simply as much insulation as possible. Seemed to me that having an air gap is good of course but not as good as having simply more insulation. I could be wrong of course! No changing it now

Oh i agree. More material is always better than air gaps.

but we're talking about incredibly deep traps, the density of the material can make a dramatic difference.

 

[Snoochers]

Oh i agree. More material is always better than air gaps.

but we're talking about incredibly deep traps, the density of the material can make a dramatic difference.

View attachment 220010

Oh that’s interesting! So less dense can be better? It’s actually a mix at the front. I got denser roxul in front or looser roxul and some less dense pink fluffy stuff mixed in in parts