EQing a dip? (Now with pictures!)

[idiot 10+ year member]

How easy would it be to fix the ~1.2kHz dip in the graph below? I'll be using the 880PRS for processing. I've never messed with an EQ in either home or car systems, so I have to ask. Doesn't seem like it would be difficult, but that's a pretty substantial dip...

I'm thinking of trying to put these bad boys in my door:

Click to read more...

 

[squeak9798 5,000+ posts]

Honestly the frequency response in that graph doesn't matter one lick since that response was not measured in your vehicle...where the speaker will be located.

That graph is not representative of the response you'll have with the speaker installed in your vehicle.

The response is going to change drastically from that graph once you install the speaker in your car.

 

[DBfan187 5,000+ posts]

Yeah idiot.

 

[idiot 10+ year member]

Couldn't you say the same about running this in someone's dorm room, since the graph was likely taken in an anechoic chamber? Yet the home theater guys are all about throwing in notch filters and ridiculously low crossover points to try and obscure the dip, despite the fact that the rest of the frequency range will no longer be flat in a real room and will require minor EQing as well. Obviously a car is a much worse environment, but wouldn't this at least indicate that a big trouble point will be around the 1.2kHz area?

I need an RTA.

 

[squeak9798 5,000+ posts]

Couldn't you say the same about running this in someone's dorm room, since the graph was likely taken in an anechoic chamber? Yet the home theater guys are all about throwing in notch filters and ridiculously low crossover points to try and obscure the dip, despite the fact that the rest of the frequency range will no longer be flat in a real room and will require minor EQing as well.

The effects of room acoustics will be much less severe than in a vehicle. So it's not quite the same comparison.

but wouldn't this at least indicate that a big trouble point will be around the 1.2kHz area?

Your vehicles acoustics and installation are going to completely swamp almost all of the driver's own inherent frequency response characteristics.

I need an RTA.

Indeed.

That is about the only way to do this.

That and a good ear......

 

[jmanpc 5,000+ posts]

auto eq on the 880 ftw?

 

[idiot 10+ year member]

Well, I have a db meter... maybe that can serve as a poor man's RTA. //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

Has anyone here installed the Usher 8945P's? I'm going to mate them with a 1" dome tweeter. It'll be my first active setup with any kind of processing, so I'll probably be back with more stupid questions before I'm done.

 

[helotaxi 5,000+ posts]

I'd be more concerned about the peaks above and below the "dip" than the dip itself.

You can get RTA software for your computer for not a lot of dough.

 

[idiot 10+ year member]

I'll probably put a lpf on the woofer somewhere around 1.6kHz, so the upper peaks won't be too much concern. My tweeters should be able to be crossed around 2kHz without an issue.

What kind of microphone would I need to run the RTA software?

 

[helotaxi 5,000+ posts]

A decent measurement mic would be best but you can calibrate a lesser one to work well enough. You will also need a mic preamp. You can get both on eBay for not a lot.

 

[idiot 10+ year member]

In that case, I have the mic but not the preamp.

Thanks for the help.

 

[DBfan187 5,000+ posts]

http://www.caraudio.com/forum/showpost.php?p=2535289&postcount=28

 

[idiot 10+ year member]

Yep, I have that Behringer mic already. Thanks for the link to the preamp and program. I'll have to pick those up eventually.

 

[ARSkemp 10+ year member]

http://www.caraudio.com/forum/showpost.php?p=2535289&postcount=28

Would it be better to use this than the auto-eq already on the 880prs or will the end result be pretty much the same either way?

 

[squeak9798 5,000+ posts]

Would it be better to use this than the auto-eq already on the 880prs or will the end result be pretty much the same either way?

Most Auto-EQs built into headunits **** ass........better off doing it the ole' fashion way