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4x FTW21's + 4x MFW15's...My HT Room results

post #1 of 58
2/11/13 at 6:23pm
Thread Starter 
Hello Fellow bassheads,

I have been trying REW since Saturday as a friend lent me his mic (ECM8000).
I am OVERWHELMED with making this work.
This is extremely hard and have no idea if my findings are accurate in any way, shape or form.

This stuff is extremely hard to understand.
I've tried the best I can and if what I'm reading is any good then I'm so unimpressed with the results!
My front stage speakers SUCK!
My bass seems ok to me (who am I to say?)

anyways here are the results.

Before Minidsp (Everything on the MiniDSP is set to FLAT!)


This after using the MiniDSP to filter the subs.


I can't believe what I'm seeing between 100HZ and 200HZ. WTF is wrong there?
I know there's a way to do better so I'm hoping to get some help.

Man I'm so brain dead for now and really need to get out of my room for a while.
I can't believe how hard this is. I wish someone could come over and do this right! redface.gif
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post #2 of 58
2/11/13 at 7:00pm
Probably crossover or phase issue. I had a severe suckout from 60-90hz, maybe worse than yours. I wired just the subs out of phase and its completely flatten my response. If your subs have phase control try that or you can play with the subs distance by changing it in you preamp/receiver or physically moving subs.
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post #3 of 58
2/11/13 at 7:10pm
Hey Fatshaft,

First off - one step at a time. This is a learning process and remember is supposed to be fun! biggrin.gif

Where are the subs located in the room? Where are they crossed over.

Don't worry, you will get it figured out!!
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post #4 of 58
2/11/13 at 7:13pm
invert button in the mini dsp and see what happens
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post #5 of 58
2/11/13 at 7:24pm
That explains why you were unhappy with your sub response even with all that firepower!! I wondered what it was you were looking to improve on by going the Si-18 route. As mentioned above, this is likely a placement/setup issue. Where are the subs crossed? Audyssey sometimes leaves a bit of a suckout at the near the crossover point, but that's easily fixed by playing with the subwoofer distance setting. That deep a suckout and at that frequency leaves me skeptical it's that issue. You can get this figured out. You've taken the first step by measuring to see what's happening. The rest is patience and experimentation.
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post #6 of 58
2/11/13 at 7:28pm
What kinda response do you get with your just your mains running full-range? Does your receiver have Audyssey?
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post #7 of 58
2/11/13 at 7:55pm
Ouch, thats a serious suckout lol. You could likely EQ that out to be decent enough.
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post #8 of 58
2/11/13 at 8:25pm
Definitely looks like your subs are out of phase with your mains. Are you changing the distance setting from what audyssey gave you? I'm pretty sure it uses that to match phase.
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post #9 of 58
2/11/13 at 8:50pm
Agreed. This looks like a combination of things however, not hard to fix. Patience IS the key and take one step at a time.

Consider adjusting: phase, subwoofer level and distance. Don't even bother EQ'ing that out. You can fix it by doing those first few things.

Trust me. You're dealing with what all of us have had to at some point.

Good luck!
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post #10 of 58
2/12/13 at 3:11am
Thread Starter 
Thanks all for your responses.
I will restart again tonight. Busy day all day today.

Some answers though.
No auddysey whatsoever...no EQ. My receiver has EzSet/EQ II. I did not use it.
Fronts are on large.
Tried reverse phase subs, tried front only, tried back only, tried front and back. It's the best I can do.
Distance setting on speakers are manually set.

I'm going to do the following:
Front subs only and post graph
Back subs only and post graph.
Towers crossed at 80 and post graph
Towers only (no subs) and post graph
All the above without the MiniDSP

Will only be able to do this tonight

Thanks all for your help.
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post #11 of 58
2/12/13 at 4:41am
^ I think sweeping the scenarios mentioned above will help drastically to work toward a solution. We will get there man!
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post #12 of 58
2/12/13 at 4:58am
Hey Fatshaft,

A couple comments:

1. Check your group delay plot, I'll bet you will see a large shift at ~150Hz. This will confirm phasal issue for the dip but wont rule out the dip being completely modal.
a. What is your room size?
b. Where are the subs placed in the room?

2. The dip location does lead one to think its a phase issue at crossover, and if your running your mains full range this could be part of the problem. The subs roll off at 80Hz which introduces phase shift and the mains are run full range(no phase shift). This could also just be a distance setting issue also.

Some things you might try:

a. Set all mains to SMALL- Re-meausure
b. Quick test- Play 150Hz test tone in REW and increase distance on subs to see if SPL goes up. Continue increasing distance until you plateau. Re-measure entire FR and see what you get.
c. Check your waterfall, do you have a bad ring @150Hz?
c. Are your subs placed 3.75 ft from a boundary or 7.5ft from a boundary by chance?
e. Are you seated any multiple of 3.75ft off walls?
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post #13 of 58
2/12/13 at 11:09am
Thread Starter 
To all,
Thanks so much for trying to help me, I greatly appreciate it.
I had to come home earlier, to eager to get this going, I'm here to learn!

I did lots of tests and will post some graphs...soon.

NicksHitachi,

1. I have no idea what a group delay plot is...sorry
2. I get the same results with the towers only...see graphs in my next post.

Please remember this is way over my head and have a lot of problems comprehending what you're asking me to do! With that in mind...
a. I cannot set mains to small...I could ONLY choose what the cutoff frequency I can set it too (it's in increments of 20 and starts a 40HZ and could go to 200HZ.)

Here's my setup:
Front


Back


My room is 17' 1" x 14' x avg. 7'
The mic is in the front row middle chair at ear height

Graphs to follow...
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post #14 of 58
2/12/13 at 11:27am
Thread Starter 
OK,

Did some graphs today as best I can.
Receiver settings:
Bass and treble OFF
LFE trim @ -6 (goes from 0 to -10)
Output levels: Range is from -10 to +10
Subs at -5
Front speakers at +3

MiniDSP settings:
Input Gain at -20 (that's freaking LOW!!)
Parametric EQ All flat
4-Way Crossover: FTW21's LPF at 120HZ, HPF at Bypass MFW15's LPF at 200HZ, HPF 10HZ
Parametric EQ 1 to 4 (all flat)


I'm posting 3 graphs...Keep note that I never change volume or any other settings when I took these measurements.

The 1st graph is:
Towers Full range ONLY
Towers Full range with Front subs in phase
Towers Full range with front subs inverted


2nd graph
Towers Full range ONLY
Towers Full range with Back subs in phase
Towers Full range with Back subs inverted


3rd graph is:
Towers Full range ONLY
Towers Full range with All subs in phase
Towers Full range with All subs inverted


the big question for me is how do I fix this? redface.gif

Thanks
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post #15 of 58
2/12/13 at 11:30am
Add +5 to your speakers level and -5 to your subs level
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post #16 of 58
2/12/13 at 11:30am
Front wall cancellation?
http://www.genelec.com/learning-center/presentations-tutorials/placingloudspeakers/wallcancellation
http://www.avsforum.com/t/676375/tackling-back-wall-cancellation-dip

If the mains' baffles are 2ft. or so from the front wall, this is a possible culprit. Then subs are crossed too low to compensate.

So maybe try turning the two inner subs 90deg, pushed against front wall and facing each other, and crossing them a bunch higher, like 200Hz? Maybe cross mains a bit higher, too.

Just a thought; should be an easy enough trial run...
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post #17 of 58
2/12/13 at 11:34am
FS - Any reason why you are running different LPFs on the MFW's and the 21's? You have them at 200hz and 120hz, right? Have you tried setting both at 100hz or 120hz?
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post #18 of 58
2/12/13 at 11:41am
First off, I generally start with the center channel when optimizing and look at the L and R secondary.

However, from what I see your problem is room/speaker/listener placement related. The response issues appear in the mains and sub graphs.

Try moving the subs out of the corners. Start with 27% distance of the wall and see if that helps.

Example 17'X 0.27= 4.5 feet off back and front walls(if possible).

Generate a waterfall and group delay plots and post them. They are tabs in REW, just click on the tabs and the data will display for the measurement you currenltly have highlighted.
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post #19 of 58
2/12/13 at 12:00pm
FS, what kind of receiver do you have?

Someone correct me if I'm wrong, but setting speaker distance by hand is generally fine, but setting sub distance (especially with multiple subs, mulitple source positions) is much more complex. I'm just curious if a receiver with some type of real auto-eq system wouldn't make all this much simpler.
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post #20 of 58
2/12/13 at 12:42pm
Thread Starter 
Quote:
Originally Posted by Jay1 View Post

Add +5 to your speakers level and -5 to your subs level

Thanks,
I added + 5 to the fronts and it seems ALOT better! see graph below
Quote:
Originally Posted by Gorilla83 View Post

FS - Any reason why you are running different LPFs on the MFW's and the 21's? You have them at 200hz and 120hz, right? Have you tried setting both at 100hz or 120hz?

No, none redface.gif I now put the back ones at 90 and the front ones at 100...thank you
Quote:
Originally Posted by NicksHitachi View Post

First off, I generally start with the center channel when optimizing and look at the L and R secondary.

However, from what I see your problem is room/speaker/listener placement related. The response issues appear in the mains and sub graphs.

Try moving the subs out of the corners. Start with 27% distance of the wall and see if that helps.

Example 17'X 0.27= 4.5 feet off back and front walls(if possible).

Generate a waterfall and group delay plots and post them. They are tabs in REW, just click on the tabs and the data will display for the measurement you currenltly have highlighted.

I cannot move my subs...I have no room to do so...especially the back ones. I have very little play in the front to move them. so sorry.
Waterfall and GD graphs...see below
Quote:
Originally Posted by wth718 View Post

FS, what kind of receiver do you have?

Someone correct me if I'm wrong, but setting speaker distance by hand is generally fine, but setting sub distance (especially with multiple subs, mulitple source positions) is much more complex. I'm just curious if a receiver with some type of real auto-eq system wouldn't make all this much simpler.

I have a HK 7550HD receiver. I have not yet ran the EzSet EQ ll yet.

OK here's the latest after making the above changes...I did however cross the front towers at 120HZ


Group Delay...hope this is done right... redface.gif


Waterfall

What does this all mean? I wish I knew!
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post #21 of 58
2/12/13 at 2:28pm
Damn man!
That is some serious woofage in that room. I can't imagine not having enough displacement there for just about anything.
Don't sweat it, you will get it all sorted out. It can take a while to get a handle on exactly what is happening and then how to go about correcting it.

Did you try measuring from any other seating locations?
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post #22 of 58
2/12/13 at 2:44pm
You have some serious room caused ringing/energy storage just below 80hz. Whoo! That needs a fixin'.
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post #23 of 58
2/12/13 at 3:04pm
Couple of things. Have you run the auto EQ at all? Perhaps you should try that after level matching the subs. The distance/delay calculations done by the receiver can be very difficult if done by hand. At least give that a try to see how or even if it makes much of a difference.

Having said that, I read up a little bit on the HK receivers and their flavor of EQ. A quick google search led to a poster from these forums who is a self-described former fanboy of HK. He said basically to run, don't walk to a receiver that has Audyssey, preferably at least the XT version. With so many issues with your response and so little ability to move stuff around your best option may be let a good EQ do its thing and then tweak from there.

Also, from the graphs of your towers, they look pretty capable to my eyes. Again, room issues dominate, but you should easily be able to cross them at 80 Hz.

Just my 2 cents.
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post #24 of 58
2/12/13 at 3:14pm
I would also try crossing your mains lower as an experiment. I like mine at 50-60Hz area. Of course, that may not work for you depending on the extension of your main.

Try lowering the xover point and take another measurement. It can't hurt, and may determine if the issue is exacerbated by the crossover as well.

BTW, those 21s look f-ing awesome!cool.gif
Edited by jpmst3 - 2/12/13 at 3:48pm
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post #25 of 58
2/12/13 at 5:33pm
Quote:
Originally Posted by Fatshaft View Post

Quote:
Originally Posted by Jay1 View Post

Add +5 to your speakers level and -5 to your subs level

Thanks,
I added + 5 to the fronts and it seems ALOT better! see graph below
Quote:
Originally Posted by Gorilla83 View Post

FS - Any reason why you are running different LPFs on the MFW's and the 21's? You have them at 200hz and 120hz, right? Have you tried setting both at 100hz or 120hz?

No, none redface.gif I now put the back ones at 90 and the front ones at 100...thank you
Quote:
Originally Posted by NicksHitachi View Post

First off, I generally start with the center channel when optimizing and look at the L and R secondary.

However, from what I see your problem is room/speaker/listener placement related. The response issues appear in the mains and sub graphs.

Try moving the subs out of the corners. Start with 27% distance of the wall and see if that helps.

Example 17'X 0.27= 4.5 feet off back and front walls(if possible).

Generate a waterfall and group delay plots and post them. They are tabs in REW, just click on the tabs and the data will display for the measurement you currenltly have highlighted.

I cannot move my subs...I have no room to do so...especially the back ones. I have very little play in the front to move them. so sorry.
Waterfall and GD graphs...see below
Quote:
Originally Posted by wth718 View Post

FS, what kind of receiver do you have?

Someone correct me if I'm wrong, but setting speaker distance by hand is generally fine, but setting sub distance (especially with multiple subs, mulitple source positions) is much more complex. I'm just curious if a receiver with some type of real auto-eq system wouldn't make all this much simpler.

I have a HK 7550HD receiver. I have not yet ran the EzSet EQ ll yet.

OK here's the latest after making the above changes...I did however cross the front towers at 120HZ


Group Delay...hope this is done right... redface.gif


Waterfall

What does this all mean? I wish I knew!

Ok your on your way!

Now rescale your graphs to cover a 60db span and from 5-500Hz, this will give us graphs comparable to the "standard" format.

Also remove all smoothing from graphs relating to subs. If your plotting mains FR a bit of smoothing helps but as low as your looking smoothing needs to be removed.

Group delay plot is useless with smoothing applied.

Waterfall shows a strong modal ring @80Hz. That needs acoustic treatment.

Now your main searing looks pretty close to the middle of the room. Since your room is 17', that puts you pretty close to 7.5 ft from a wall, thats the low pressure minima for 150Hz. Since your subs are up against the front and back walls your stimulating that mode fully.

Not sure what else to suggest..... Hopefully the brains are on the way! biggrin.gif
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post #26 of 58
2/12/13 at 6:21pm
Thread Starter 
Again folks, I just want to thank you all for trying to help me out.
It's also discouraging reading some of the replies...I have a lot to do still !!!!
My room is not finished as I still need to do all the acoustic panels and l believe this will help my situation out.

To answer some of the questions.
I have tried the EQ wizard and it sucks completely!
It's very good to correct the mid and highs but it also DESTROYS my lows.
It cuts from about 15 hz down dramatically. so f'k that!

l did not try to measure from another location
Yes my towers play pretty low but it lacks the highs it seems.
I tried crossing them lower and it kills the 80, 90 and 100 hz pretty bad. so its back to 120HZ.

I'm pretty freakin tired right now and going to bed.
I'll probably experiment more this weekend.

Here's where I am for now....I redid my front stage and this is how it looks now.


Nick,
Here's the graph you asked for...hope its what you asked for.


I have a lot to do...I'm considering changing my towers now.

Thanks all again....what a great place to learn this stuff and you guys are great!
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post #27 of 58
2/12/13 at 6:32pm
That looks much better! smile.gif
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post #28 of 58
2/12/13 at 6:44pm
+1!! Getting those tweeters at ear level probably helps out in the upper range in and of itself too smile.gif They were a little high on top of those other cabs.
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post #29 of 58
2/12/13 at 6:54pm
Quote:
Originally Posted by Fatshaft View Post

Again folks, I just want to thank you all for trying to help me out.
It's also discouraging reading some of the replies...I have a lot to do still !!!!
My room is not finished as I still need to do all the acoustic panels and l believe this will help my situation out.

To answer some of the questions.
I have tried the EQ wizard and it sucks completely!
It's very good to correct the mid and highs but it also DESTROYS my lows.
It cuts from about 15 hz down dramatically. so f'k that!

l did not try to measure from another location
Yes my towers play pretty low but it lacks the highs it seems.
I tried crossing them lower and it kills the 80, 90 and 100 hz pretty bad. so its back to 120HZ.

I'm pretty freakin tired right now and going to bed.
I'll probably experiment more this weekend.

Here's where I am for now....I redid my front stage and this is how it looks now.


Nick,
Here's the graph you asked for...hope its what you asked for.


I have a lot to do...I'm considering changing my towers now.

Thanks all again....what a great place to learn this stuff and you guys are great!

Wow that looks pretty good! Is that without eq?

Just moving those two out the corners helped out tremendously. Also moving your mains out the corner a bit also is prob a good thing.

Like beast said getting those tweeters closer to ear level is a good thing too. Youll no doubt see better upper frequency extension the closer you get to "on axis" with the tweets.
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post #30 of 58
2/13/13 at 5:06am
That is a step in the right direction, at least in the bass dept.

You might even benefit from some room treatments.
Edited by jpmst3 - 2/13/13 at 5:32am
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