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Alan are you using a 100Hz crossover for mains and center?
100hz for everything actually (including heights and surrounds).
 
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Finally something to report! Putting in some work with REW and suggested tweaks per above!

Not sure if I'm doing it right or if I'm improving things lol; here it is:

To clarify the above results were a result of sw dist tweak and xo tweak (as suggested above) plus a 2 decibel boost PEQ I added to 20hz on iNuke amp. Is it OK for me to add small EQ to subs or is frowned upon?

250 hz a ridiculous setting for my AVR XO?

MDAT attached for both before and after - other pertinent info from my measurements?

Thanks in advance for any help!
I would say it is...why such a high crossover?? What speakers are you using?
 
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I would say it is...why such a high crossover?? What speakers are you using?
Just guess and check mostly while measuring last night. My transition and low end seemed smoothest with the high XO as opposed to lower. My subs are PA-460 speakers so they have a naturally rising response (see 'rexus' SW build thread in sig if interested). The measurements just seemed smoother the higher I took the xo, finally topping out at 250hz.

To step back, I'm realizing how critical mic placement is to consistent measurements. This original graph I posted (directly below), w/ the dips at 80hz, is NOT representative of my setup with the mic position I am currently using:



Rather, Graph #1 on THIS POST represents the default aud measurements in my HT while Graph #2 in THIS POST represents where I stand currently.

Suggestions on where to go from here? More work on curves or tackle reflections or...
 

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100hz for everything actually (including heights and surrounds).
Thought so my friend, plan on switching to a higher XO as well for all speakers, I believe digler is using DIYSG 1099s to answer your question about what speakers he has and I can't imagine using a 250Hz XO with them as I have the same speakers.............
 

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Thought so my friend, plan on switching to a higher XO as well for all speakers, I believe digler is using DIYSG 1099s to answer your question about what speakers he has and I can't imagine using a 250Hz XO with them as I have the same speakers.............
Yep 1099's all mains for my setup. No scientific strategy being employed on my part, I'm the first to admit it. I was encouraged by @AustinJerry and others to guess and check so I'm hacking through best I know how.

Open for suggestions :)
 

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Yep 1099's all mains for my setup. No scientific strategy being employed on my part, I'm the first to admit it. I was encouraged by @AustinJerry and others to guess and check so I'm hacking through best I know how.

Open for suggestions :)
Yea I would imagine you don't want to cross over much higher than 60 or 80hz. You want to be able utilize the midbass of dual 10" woofers on those beasts!
 

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Yea I would imagine you don't want to cross over much higher than 60 or 80hz. You want to be able utilize the midbass of dual 10" woofers on those beasts!
LOL - keep it honest all its my only hope. Thanks to all for input!

I'll dial the xo back and do more measurements see what we've got... :)
 

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250Hz seems a bit high for the crossover. Parts of human voices will be coming from the subs—not desirable. And please be consistent with the vertical scale on your screenshots.

Edit: It is also critical that you develop a procedure to ensure that your mic is positioned in exactly the same spot for different measurement sessions. Tip of the mic exactly at ear height, pointed to the ceiling, and centered precisely on the centerline between left and right speakers.
 
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Even if MLP is not centered?
I thought most important measurements were at MLP.
:confused:
Sorry, in my world I cannot conceive of anything but a symmetrical layout. What kind of a sound stage would there be if the MLP were closer to the left or right speaker, and not directly in front of the center speaker?
 

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Sorry, in my world I cannot conceive of anything but a symmetrical layout. What kind of a sound stage would there be if the MLP were closer to the left or right speaker, and not directly in front of the center speaker?
As I'm sure you know, some of our setups are in a common room (mine is in my living room), and compromises sometimes will have to be made. Although my wife's seat is significantly off center, she really couldn't care less. This is why my seat is only about 1' off center. ;)

We envy guys like you that can have a perfectly symmetrical setup!
 
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As I'm sure you know, some of our setups are in a common room (mine is in my living room), and compromises sometimes will have to be made. Although my wife's seat is significantly off center, she really couldn't care less. This is why my seat is only about 1' off center. ;)

We envy guys like you that can have a perfectly symmetrical setup!
I have an advantage, acoustically speaking, because I am a single guy with a perfectly-placed MLP, and no WAF getting in the way of my room treatments. :)
 

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Ever been to a musical event where you weren't directly in front of the lead singer?
For that reason, I don’t go to live music events. ;)

I retract my original recommendation on where to place the mic. Place the mic in the MLP, where ever that might be. But placing it in the same spot each time is important to producing consistent measurements. Can we agree on that?
 

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Ever been to a musical event where you weren't directly in front of the lead singer?
And in that situation, the sound is skewed to one side....luckily, in our home theaters/audio rigs we can adjust speaker distances and/or balance to overcome these sort of issues, for the MLP at least.
 

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I would like to pass on my experience with measurements taken on the centerline of the room. In my home theater, we have 2 reclining Ekornes chairs for my wife and I, i.e. 2 MLPs, and a small table between them. They are about 2/3 of the way back from the front wall of the room. The table is on the long centerline of the room. Behind those chairs is a 3 seat Ekornes sofa that is typically occupied by dogs unless we have a people over for movie night and then they have to negotiate with the dogs for a seat on the sofa.

The first time I ran the Anthem Room Correction (ARC) software, I decided to make a measurement at my chair, my wife’s chair and 2 of the seats on the sofa as I wanted all seats to get as good a sound as possible, not just my seat. I decided to add a 5th position just in front of the table and when I did the measurements, ran that position first. After the run, the ARC software informed me that it was capable of calibrating at the reference 75 dB level, but lowered the target to 65 dB! I was shocked as I have a gazillion watts of power in my various amps and subwoofer and can play the system very loud indeed.

I consulted with Anthem and they had me look at the individual measurement positions for the subwoofer channel and sure enough for position 1, the one on the centerline of the room in front of the table, the was a huge 25 dB dip at about 38 Hz. The sub was only doing 40 dB at that spot! The other “real” seating positions looked OK. Obviously, the measurement taken on the centerline of the room was experience a null in the room modes and since it was the first measurement position, ARC interpreted that as the MLP. For my next ARC run I chose my seat as the MLP and all was well. Now with the addition of a 2nd subwoofer, I can get a very good response at both my and my wife’s chair and the seats on the sofa are good as well.

So, if you want your MLP to be on the centerline of the room, beware that it may well be in a null in the room modes that will be hard to overcome. The sound may actually be better and more similar to the rest of the room a foot or two off center.

With stereo reproduction, being centered between the L&R speakers was the sweet spot. If you moved off center very far, then precedence would shift the soundstage to the nearest speaker. With home theater we have a center channel speaker and the whole point of that speaker is so that those seated off center will get the dialog coming from the center of the screen, regardless of their position on or off axis. That is why it is also considered important that the 3 speakers up front be ideally the same, vertically orientated with tweeters at ear height. That produces the most realistic pans and coherent front soundstage for seats on and off the centerline.

So I would debate the idea that the MLP for home theater should be on the centerline of the room and that measurements there are the best way of assuring good results for other seating positions. If your MLP is on the centerline and you don’t care about any other seat in room, fine.
 

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For that reason, I don’t go to live music events.
The contact highs more than compensate for the hearing damage.
I retract my original recommendation on where to place the mic. Place the mic in the MLP, where ever that might be. But placing it in the same spot each time is important to producing consistent measurements. Can we agree on that?
Wasn't disagreeing with you earlier, simply replying to your "What kind of a sound stage would there be..." question. For real world situations where the row of seating has an even number of seats (like 4 across or a love seat), initial mic placement can be at the MLP or between the two middle seats (share the compromise). Neither placement is wrong, just a small (half-seat) difference in delay & level settings. Not enough to wreck the presentation. Probably an even smaller difference in room correction, since EQing decisions are based on multiple measurements.
 

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If your MLP is on the centerline and you don’t care about any other seat in room, fine.
That describes my situation accurately. But I don’t disagree with the other good points you make. If the MLP is located at the side-to-side midpoint of the room, steps must be taken to compensate for the null at that point. Good bass is certainly attainable—that’s why we use REW!
 
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So, if you want your MLP to be on the centerline of the room, beware that it may well be in a null in the room modes that will be hard to overcome.
Yup, all the odd numbered (1st, 3rd, 5th, etc) width modes will null at the midpoint of room width. But that's pretty easy to overcome. If you have a single subwoofer, place it in the null. If you have two subwoofers, place them on both sides of the null. That gets rid of those modes, minimizing the nulls (and peaks) caused by them.
 
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