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REW Measurement newbie help - what adjustments would you make?

KasPM

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Sep 18, 2023
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I ran Audyssey XT32 MultiEQ on my Denon x3800h. Dynamic eq off, MultiEQ XT32 on Reference. I have 2 floorstanders, and dual 13" sealed subs in a 13.5x16x7.5 room - 1600 cu ft. The subs have limited placement options, partially due to room layout, partially to WAF. But I used Room SIM to try to get the best options within those confines. I then used REW to measure all xover points from 40 to 200 and found the "flattest" REW measurement was 100 so I set the xover to that. I applied 1/6 smoothing to get the measurement below. A few questions:

1. There's a rise between 30hz-40hz - what should I do about this if anything?
2. There's a dip between 80hz-200hz - is that speaker placement/room dynamics, or is there a setting I should change?
3. Same question about the rise between 200-500?
4. Anything else you would change in the system from this measurement?

TIA

L80.jpg
 
Last edited:

ozzy9832001

Senior Member
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Feb 19, 2023
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I ran Audyssey XT32 MultiEQ on my Denon x3800h. Dynamic eq off, MultiEQ XT32 on Reference. I have 2 floorstanders, and dual 13" sealed subs in a 13.5x16x7.5 room - 1600 cu ft. The subs have limited placement options, partially due to room layout, partially to WAF. But I used Room SIM to try to get the best options within those confines. I then used REW to measure all xover points from 40 to 200 and found the "flattest" REW measurement was 100 so I set the xover to that. I applied 1/6 smoothing to get the measurement below. A few questions:

1. There's a rise between 30hz-40hz - what should I do about this if anything?
2. There's a dip between 80hz-200hz - is that speaker placement/room dynamics, or is there a setting I should change?
3. Same question about the rise between 200-500?
4. Anything else you would change in the system from this measurement?

TIA

View attachment 312752
1) I wouldn't worry about that far down into the spectrum unless there is a very specific use case where it's annoying. Most modern music doesn't go that low. In movies it would just add a bit more umpf to an explosion.

2 & 3) If you factor out the rise in question 1, the response is relatively flat from 40 to 250. you see a rise from 300-500 probably from constructive interference from a surface closer to the speakers. Quite possibly the front wall, sidewall or desk (if it's big enough), if they are close to them. You could knock the peak down, but if it's reflection based, the EQ will make it sound weird. I'd experiment with it and see if you like it dropped about -5dB. If the speakers sound a bit bright, you can drop apply a shelf filter from about 1.25khz about -2.5dB - -4dB (depends on taste).

Otherwise the measurement looks fine. If the room is untreated that's actually a really good response. You can get a decent sense where the issues lie if you take measurements of both speakers separately. You should post those results as well as the entire .mdat file from REW in a zip and let others take a look at the other graphs and all.
 

neRok

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Oct 7, 2022
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1. There's a rise between 30hz-40hz - what should I do about this if anything?
Your 16 foot room has its first mode at ~34Hz. You should have seen this in REW Room Sim.

2. There's a dip between 80hz-200hz - is that speaker placement/room dynamics, or is there a setting I should change?
The 16 foot length also has modes at multiples of ~34, such as ~68 and ~103Hz. And it seems you have a bit of null action at those frequencies.

But actually, it does seem quite low between 50 and 200Hz. It's hard to tell if 250-400Hz is a peaking problem, or if your sub and speakers are not time aligned causing some cancellation 50-200Hz. But the real head-scratcher is 500-1000Hz, because I wonder if that is a broad null from the room or from the speakers? The massive rise in treble 1-10kHz suggests the speakers are like that. What model are your speakers?
 
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