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I just finished my first real DIY install and I'm frustrated with EQ. I've got a 3 band parametric EQ. Using mobile tools and the built in iPhone mic I managed to achieve the RTA reading pictured below. I attempted flat as possible all the way through, with a boost in bass and roll off in the extreme highs. After doing this I gave a listen and DO NOT like it. It's just not right. I reverted to tuning by ear so I can enjoy the system for now, but I'd love some tips on how to maximize my system cause I definitely think it has more potential than I'm getting at present.

For instance, would a simple octave equalizer get me pretty close or am I needing a DSP to really do anything useful? Is all this pointless until I get a better mic?

Thanks in advance!

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im going to assume its a mono 3 band eq? thats not really going to be of much help. im actually surprised that you were able to get the response that you did with that. but having left/right eq is a whole new ball game
 

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im going to assume its a mono 3 band eq? thats not really going to be of much help. im actually surprised that you were able to get the response that you did with that. but having left/right eq is a whole new ball game
OK Ok... understand...

Any thoughts on if the iphone and app is somewhat decent or is this all pointless until I get a better mic??
 

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I'll look to upgrade my EQ capability in the future and just enjoy it for now thanks...
What you can't see due to not enough resolution here, is if there's any significant dips or spikes that is making the response unpleasant. Its like looking through beer goggles or something like that, you're just not able to see the nasty.

Were you measuring that all left, or all right? Make sure to not measure with both playing at once.
 

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What you can't see due to not enough resolution here, is if there's any significant dips or spikes that is making the response unpleasant. Its like looking through beer goggles or something like that, you're just not able to see the nasty.

Were you measuring that all left, or all right? Make sure to not measure with both playing at once.
1/3rd octave is enough. and measureing left vs right would be pointless considering he has a mono 3 band eq
 

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1/3rd octave is enough. and measureing left vs right would be pointless considering he has a mono 3 band eq
Yeah exactly, pointless. That was my point. But measuring left and right separate (and then averaging together) is vital to understand the true response, excluding cancellation effects at various frequencies.

I contend 1/3 octave isn't enough (always) though. Not after picking up and fixing some things in a build recently. Sometimes you have to get surgical.

edit: Solution, on the cheap. Run a JBL MS-2 (about $40!) through a device with an aux-in, and it will run an auto-cal automatically for you, with a pretty solid target curve. Then, enjoy (And turn the bass button back on, it defaults OFF)
 

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edit: Solution, on the cheap. Run a JBL MS-2 (about $40!) through a device with an aux-in, and it will run an auto-cal automatically for you, with a pretty solid target curve. Then, enjoy (And turn the bass button back on, it defaults OFF)
Cool idea thanks! I'll look into it and post an update if I can get around to it...
 

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The 3-8 KHz range looks very hot for a start, but as already mentioned there's little one can do with a 3 band parametric EQ.
 

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all this feedback and the one thing that no one is asking is how you measured the response.





Was the response measured in the car with the phone/mic held up in front of you? you in the backseat waving the mic around? mic pointed up in the air, mic pointed straight ahead, etc?... this information is vital.
 

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Discussion Starter · #15 ·
all this feedback and the one thing that no one is asking is how you measured the response.





Was the response measured in the car with the phone/mic held up in front of you? you in the backseat waving the mic around? mic pointed up in the air, mic pointed straight ahead, etc?... this information is vital.
removed the headrest on driver side and the mic pointed forward and stationary. doors closed. engine and ac off.
 

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You were holding it with your hand from the backseat?

I ask because all these things can have an effect. Your hand will cause the response to be different than it would look if you wedged it between the headrest, or simply laid the phone on the seat where the headrest was.

Now what exactly these changes can cause is hard to say. But my point is that people are giving you input when they don't know the setup and that can lead to bad advice (I'm not knocking you guys, but I am being real).

So, again, I'm asking so everyone can get a clearer picture of what is going on when you take these measurements and hopefully give you more accurate feedback.
 

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You were holding it with your hand from the backseat?

I ask because all these things can have an effect. Your hand will cause the response to be different than it would look if you wedged it between the headrest, or simply laid the phone on the seat where the headrest was.

Now what exactly these changes can cause is hard to say. But my point is that people are giving you input when they don't know the setup and that can lead to bad advice (I'm not knocking you guys, but I am being real).

So, again, I'm asking so everyone can get a clearer picture of what is going on when you take these measurements and hopefully give you more accurate feedback.
truth.

even then, it's still a single measurement point and can vary pretty greatly, especially above beaming (OOOOOOO the 2015 buzz word!), if you move it an inch. who knows how accurate the model-specific microphone calibration is from device to device.

but it's really not much different with a real rta or even the fancy multi-mic wizardry we've seen as of late.

which is largely why i still just use an rta as a tool to work out the obvious response issues, or to help identify specific frequencies i'm having issues trying to locate by ear...while i'm sitting in the car with it on the hood in front of me, heh. call me old fashioned, but body and head shadowing play a huge role in the perceived response.

so getting back to the op's desire to work with what he has...and adding on to where i think erin's going... move the phone around, slowly, and watch what it's doing from the left side of the headrest to the right, up and down both horizontal, vertical, and tipped up/down... watch for clues of the average response around your head... identify anything that isn't fitting your desired curve consistently, and work those out.

is your parametric eq selectable frequency center or a fixed point?

you can definitely pull off a reasonable curve and image with very basic stuff. it won't be laser competition grade imaging, but you should be able to get a convincing stage with just basic head unit time alignment controls and level adjustment via the balance setting. you don't *have* to have separate 31-band eq for left and right.
 

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Well, above 5k (ish), as long as that mic is in the vicinity of where the head should be, you should be OK. Below that, yeah the slightest movement changes things a lot. I use 7 to 8 (depending on left or right) measurements and average them.

Erin brought up a great point though, how you measure (and what you measure with, but we already knew that from post 1) does matter and should be brought up early.

I'm back to the MS-2 as a possible solution if there's a weird response, you are using an aux-in (and thus can even use the MS-2), and want to not get additional processing power in the system right now. Reading up on it, it looks like Andy was able to make a device that, with a simple calibration run (single location, right in front of your head) and a sophisticated processor for what it is, it can get close to your target curve and then you can use the 3 band parametric for little tweaks.
 
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