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I've been playing around with WinMLS and a ECM 8000.
The FR of the midbass drivers, Mpyres65, have serious dips and peaks (+- 15dB) at the leasening position. The nearfield measure FR is very nice and flat, so the problem is an install issue.

With the PEQ and XO on the 701 I could flatten the response but not better than +- 8Db, not very good.

The drivers are flush mounted at the stock location, low and forward.
The midranges and tws are at the kicks, close the the woofers, fairly on axis. No problem here, some minor dips and peaks but workable with the EQ.

One insteresting thing is that both sides have similar response. Playing together in phase acentuates the problem. Fliping one side flatten the FR at the listening position but sounds out of phase...

What options do I have to correct this problem?
Swapping drivers?
Go for a kickpanel midbass install onaxis?
Making some sort of door panels aligning the drivers more on axis?
More processing...
Live with it... :confused:
 

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This is a very common problem with midbass response. You likely have some cancellation going on. The only solution is to alter the radiation pattern (not likely) or attenuate the reflected wave (another pretty tall order). Try some thick blankets at various positions on the center console/transmission hump and see what happens. If you are door mounted (sounds like you are) then you will want to try blankets against the firewall as well. The blankets will likely fix the problem but only after they are so thick that you can't drive with them in place.

Good Luck
 

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Yeah, unfortunately this is the challenge of car audio. What you're seeing is the reason npdang's signature reads "a speaker is only as good as the room you put it in."

Doubting the results? Try this...

Download some test tones at different frequencies (preferably at one of your big dips you measured) and take a listen. I guarantee it'll be an interesting experience. ;)

Now, try to fix some of those frequencies with phase/time issues using independent L/R eq (assuming you have the capability). Notice anything? (Unfortunately the answer will probably be NO :( )

So you want a solution? The only real one is to put your house on wheels ;) Second best would be perfect drivers installed in perfect locations at perfect angles with perfect absorbers in the perfect places (unfortunately what's even harder than saying that 10 times fast is trying to fit a 72" foam bass trap in the driver's footwell). Third best would be frequency dependent phase/time correction processing (we're just starting to see this technology take shape and it has a ways to go).
 

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Yep, not a WinMLS problem. I would be doubtful if you got +-3 on the whole FR. +-8 is a good effort indeed.
 

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OP I'm interested know at what frequencies your peaks and dips occur.
I have a peak @ 250hz and a dip @ 500-630 hz.
Although EQ helps, it's still there.
 

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I have a dip at 80 @ -5dB, 125/160 @ -4dB, 315/400/500 @ -6/6/4dB and 600/800 @ -8/6dB with peaks from 2k through to 315k measured using the AC SA-3050A.

So, I think if you only have one or two peaks or dips, you're not doing too badly...
 

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I've been playing around with WinMLS and a ECM 8000.
The FR of the midbass drivers, Mpyres65, have serious dips and peaks (+- 15dB) at the leasening position. The nearfield measure FR is very nice and flat, so the problem is an install issue.

With the PEQ and XO on the 701 I could flatten the response but not better than +- 8Db, not very good.

The drivers are flush mounted at the stock location, low and forward.
The midranges and tws are at the kicks, close the the woofers, fairly on axis. No problem here, some minor dips and peaks but workable with the EQ.

One insteresting thing is that both sides have similar response. Playing together in phase acentuates the problem. Fliping one side flatten the FR at the listening position but sounds out of phase...

What options do I have to correct this problem?
Swapping drivers?
Go for a kickpanel midbass install onaxis?
Making some sort of door panels aligning the drivers more on axis?
More processing...
Live with it... :confused:
Are you gating your measurements?

Check out my thread on "improving the sound for $80"

I give some info on how to get decent measurements in the car

As the other posters noted, reflections in the car are a *****. About all I can do is use the measurements to find treatable reflections and resonances in the speaker, enclosure, and car itself.
 
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