DIYMobileAudio.com Car Stereo Forum banner
1 - 6 of 6 Posts

· Registered
Joined
·
2 Posts
Discussion Starter · #1 ·
After tuning for hours and days, I just want to give up. But, I thought I would ask for some direction in hopes that it will kindle my fire again.
I've tried to tune my active 4-way to flat, just to see how it goes. It sounded like...well horrible. So I thought I would let the AutoEQ do its thing in my DEX-P99RS and analyze those curves.

Can someone tell me what is going on in my midbass and midrange drivers in terms of response?

Midbass: The huge dips at 135Hz and 235Hz and the peaks at 380Hz and 455Hz - Why do they level out when both speakers are playing?
Midrange: Same thing - dips and peaks level out?

I've attached 3 graphs (Midbass, Midrange, and Overall responses). Blue is Left, Red is Right, Black is combined response.

Can somebody point the way to a better understanding please?

P.S. - It sounds great (for some reason).

Rectangle Slope Purple Font Plot
Rectangle Slope Plot Font Line
Rectangle Slope Purple Plot Font
 

· Registered
Joined
·
2 Posts
Discussion Starter · #2 ·
Ok, so after a little fiddling around I came up with the following graphs. What I did was record the noise floor (I'm using a Behringer ECM-8000) and exported that as a text file. Then I used that as my microphone calibration file. (My thought was that like in astrophotography, you take flats/darks or pictures with the lens cap on, and subtract them from your pictures, thus subtracting the camera "noise", and getting only the actual picture (photons)).

The first graph shows my midbass and midrange (Red) with the noise floor (Light Green) at the bottom. I then added 60dB to the noise floor response to line up with the driver measurements (Dark Green).....it seems like the big dips and peaks line up.

The second graph is where I subtracted the noise floor (Light Green) from the mike, using it as a calibration file.... and they look more like what the speakers "should" look like.

Any thoughts?

I'm thinking I need to try a different mic.

Rectangle Green Slope Plot Font


Rectangle Slope Plot Font Line
 

· Registered
Joined
·
6,539 Posts
First off stop using auto eq !!! It’s trash

do this

make sure your mic sample rate and input sample rate match in REW

if it’s 48k use 48k for mic properties and in REW!!!

use periodic noise that’s pre recorded 16k samples. For now until you know your sound card cal is proper

the use real time rta and set to 32 averages and 16k samples

nice the mic around your head while playing noise that’s pre recorded on a media , like cd is good

then, don’t boost EQs
Just make cuts in your responce to make response flat while taking averages....

then listen as you go a d make improvements as needed

auto eq is..... difficult

do t do separate left and right eq work , do both left and right eq as a sum first

Or do only the left and apply same settings to the right , that will get it to at least “sound good”

make sure you have mic cal loaded also

then fine tune from there .....

i won’t reply this any more
 

· Registered
Joined
·
4,501 Posts
Ok, so after a little fiddling around I came up with the following graphs. What I did was record the noise floor (I'm using a Behringer ECM-8000) and exported that as a text file. Then I used that as my microphone calibration file. (My thought was that like in astrophotography, you take flats/darks or pictures with the lens cap on, and subtract them from your pictures, thus subtracting the camera "noise", and getting only the actual picture (photons)).

The first graph shows my midbass and midrange (Red) with the noise floor (Light Green) at the bottom. I then added 60dB to the noise floor response to line up with the driver measurements (Dark Green).....it seems like the big dips and peaks line up.

The second graph is where I subtracted the noise floor (Light Green) from the mike, using it as a calibration file.... and they look more like what the speakers "should" look like.

Any thoughts?

I'm thinking I need to try a different mic.

View attachment 319729

View attachment 319730
That’s not how a calibration file works, just make sure your levels are 20db over the noise floor and use the mics actual calibration file 🙈
 
1 - 6 of 6 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top