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My REW measurement

Photony83

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Trying to get the most of my current setup with REW as I have the minidsp SHD coming in next week and trying to get this current set up maximized to compare it against the Dirac live method. I did this once before early in my journey to some success but its been a while. measurement below in my current setup in 16x12x8 feet room. sadly front wall is the 16' wall and I can't change that.

equipment is Yamaha Avantage RX-A2080 with its room correction, Ascend Sierra 2EX speakers, SVS PB2000.

This is my second attempt at trying to optimize this room.

Does anything stand out as an obvious area I need to fix?

so here it is :

if I should change the scale to something else let me know.



SPL and Phase 20-20k.jpg



SPL and Phase 10-200hz.jpg



waterfall.jpg
 

vavan

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Photony83

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Vasr

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Is this just a single mic position measurement? If so, I wouldn't correct based on that. Do a short RTA sweep around the listening position with extent based on what the listening positions are likely to be.

Based on this alone, looks good above 600hz. The 400hz+/- 100hz dip could be problematic to tonal balance.

Doing 5 position sweeps will give you a better idea of what is likely room modes and what may not be fixed with correction. You can average out those and then correct.
 
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Photony83

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ok got the miniDSP SHD sooner than I expected and just jumped to the first measurement. this is with my Sierra 2ex front and 1 sub.


Dirac live meaurement .jpg


1606019926092.jpeg


So just trying to make some conclusions based on the waterfal: below 60 it really cleaned up but is that bc it is cutting off the frequency? I am using the minidsp for music listening only so this might be ok? Initial impressions are I can hear cleaner bass response but maybe psycoacoustic bc I am seeing it on the graph? so hard to judge and its only been a few hours.

How can I fix this dip at 60hz and 180/190hz? more tinkering with Dirac or something in my room? seems awfully big drops.
 

Vasr

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Just let Dirac take care of it and them measure and see what you get.

The 60hz null is very difficult to get rid off with one sub. You can try placing the sub at a very different location to alter reflection behavior.

What is the crossover frequency set at? What are the crossover slopes?

Measure the sub and speaker separately to see what the best crossover is. It might also give a clue as to why you are getting the 180hz trough.
 

Absolute

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That narrow dip around 60 hz could be interference between left and right speaker (or sub) or room related SBIR.
The other one is usually SBIR (speaker to wall/floor reflection causing cancellation).

*General information following*
It looks like the target is the Harman curve based on your frequency response. To that I'd like to point out that the Harman curve is intended to look like that after at least 6 different measurements around the listening area and averaged.
The best way to check for response both before and after room correction is to do the Moving Mic Measurement technique (Generator in REW, full range Pink noise at 16k and using RTA window set at 16k and forever averaging) where you're holding the microphone and moving it in circles around your listening area.

Doing this you will get the equivalent result of 32 measurements averaged in a short time-frame - and it will have a better correlation between measured response and subjective impression of the sound.

When you use Dirac, always measure with many points even if the one-point REW measurement afterwards doesn't look as nice.

I'll demonstrated with Audiolense. Here's a picture of MMM result before (blue) and after (red) Audiolense after a one-point measurement correction;

MMM original M2 (Blå) vs MMM Etter Audiolense (Rød).jpg


It actually made stuff worse. Interestingly enough the before measurement is closer to the Harman curve than the one corrected to it with a target curve. Even more interesting is the fact that this is measured with a Harman speaker, JBL M2 where there's no room correction above 60 hz in the blue graph.
 
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