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Discussion Starter #1
Recently I started build up 2 way active front stage and a rear sub in a 4 door sedan. But I have no Idea to proper setting the crossover point and time alignment.
Speaker build up: 6.5 inch mid at door panel, tweeter on dash, 12inch sub in trunk

My current crossover point is:
LPF: 60hz
H-MID: 63hz, 18db
L-MID: 3.2khz, 18db
HPF: 3.2k, 24db

1. Any suggestion for crossover point and db/oct. What is the 0 to -12db level meaning found in my setting also.
2. Now my tweeter is on dash, which facing angle is the best.
3. Time alignment should image at center of dash or driver left & right ear. Its possible to setup for front both driver and passenger.

261287
 

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Start with 24dB slopes all around. Set a LPF of 80hz on the sub, and 80hz HPF on the mid. Your tweeter crossover point is probably fine, depending on the tweeter you are using.

The 0-12dB level matching is just that, a way for you to reduce SPL in order to match the levels of all speakers.

If you have a 1” or smaller tweeter, I wouldn’t worry too much about the angle at all, but you can always experiment with temporary positions.

Time alignment should put the center image between the speakers, so middle of the dash, ideally out at the front of the hood where a hood ornament would be. It is not possible to optimize the stage for both the driver and passenger. Some very complicated systems so a decent job at 2 sear tunes, but they aren’t easy, and still compromise the driver’s stage.
 

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Start with 24dB slopes all around. Set a LPF of 80hz on the sub, and 80hz HPF on the mid. Your tweeter crossover point is probably fine, depending on the tweeter you are using.

The 0-12dB level matching is just that, a way for you to reduce SPL in order to match the levels of all speakers.

If you have a 1” or smaller tweeter, I wouldn’t worry too much about the angle at all, but you can always experiment with temporary positions.

Time alignment should put the center image between the speakers, so middle of the dash, ideally out at the front of the hood where a hood ornament would be. It is not possible to optimize the stage for both the driver and passenger. Some very complicated systems so a decent job at 2 sear tunes, but they aren’t easy, and still compromise the driver’s stage.
 

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Discussion Starter #4
Start with 24dB slopes all around. Set a LPF of 80hz on the sub, and 80hz HPF on the mid. Your tweeter crossover point is probably fine, depending on the tweeter you are using.

The 0-12dB level matching is just that, a way for you to reduce SPL in order to match the levels of all speakers.

If you have a 1” or smaller tweeter, I wouldn’t worry too much about the angle at all, but you can always experiment with temporary positions.

Time alignment should put the center image between the speakers, so middle of the dash, ideally out at the front of the hood where a hood ornament would be. It is not possible to optimize the stage for both the driver and passenger. Some very complicated systems so a decent job at 2 sear tunes, but they aren’t easy, and still compromise the driver’s stage.
So that I will put 24db slope for starting and 0-12db put it at 0db.
My tweeter is 1 inch in size.
I didnt understand your center image position is in where. Center of dash or driver.
 

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Stary with the levels at 0dB and turn them down if that particular speaker is too loud. What are you using as a DSP?
It should be in the center of the dash, but ideally it would appear to come from outside the car, out on the hood of the car.
 

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So that I will put 24db slope for starting and 0-12db put it at 0db.
My tweeter is 1 inch in size.
I didnt understand your center image position is in where. Center of dash or driver.
That would be the center of the dash, or ideally like gijoe said out on the center of the hood. Think about a concert hall; the soundstage is out at a distance in front of you.
 

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Discussion Starter #7
Stary with the levels at 0dB and turn them down if that particular speaker is too loud. What are you using as a DSP?
It should be in the center of the dash, but ideally it would appear to come from outside the car, out on the hood of the car.
center of the dash in driver side or direct
Stary with the levels at 0dB and turn them down if that particular speaker is too loud. What are you using as a DSP?
It should be in the center of the dash, but ideally it would appear to come from outside the car, out on the hood of the car.
261298
261299

which reference point for T/A. I am using Alpine CDA 9855
 

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Discussion Starter #8
That would be the center of the dash, or ideally like gijoe said out on the center of the hood. Think about a concert hall; the soundstage is out at a distance in front of you.
Can u help to point out the reference point for T/A in picture for me more understanding.
 

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So time alignment is pretty straight forward. i use my umik mic and put it where my head would naturally be when I am driving. I set the tip of the mic basically between my ears.
then get a tape measure and measure each speaker from the tip of the mic. So measure toeach tweeter, and mid and sub. Write these numbers down. Then go to http://tracerite.com/calc.html

put the measurements in the proper box and hit calculate. The results are your specific time alignment numbers in ms. Input those numbers in your dsp/TA feature on your head unit and your done. Now the fun starts with eqing the system and level matching the speakers to give you the centered sound stage.

another good read is
https://testgear.audiofrog.com/wp-content/uploads/2018/03/A-Straightforward-Stereo-Tuning-Process-and-Some-Notes-About-Why-it-Works.pdf
 

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Can u help to point out the reference point for T/A in picture for me more understanding.
The only reference point you need is the speaker's voice coil. Simply measure (as accurately as you can) from a fixed point around the listening position (you can devise a rig on the head rest, or hang something from the head liner) to the center of the speaker. Typically there is a dust cap in the way, so add just a bit of distance to account for that. You are simply measuring from the voice coil of each speaker, to the fixed listening position. That's it, you're done with TA.
 

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Discussion Starter #11
So time alignment is pretty straight forward. i use my umik mic and put it where my head would naturally be when I am driving. I set the tip of the mic basically between my ears.
then get a tape measure and measure each speaker from the tip of the mic. So measure toeach tweeter, and mid and sub. Write these numbers down. Then go to http://tracerite.com/calc.html

put the measurements in the proper box and hit calculate. The results are your specific time alignment numbers in ms. Input those numbers in your dsp/TA feature on your head unit and your done. Now the fun starts with eqing the system and level matching the speakers to give you the centered sound stage.

another good read is
https://testgear.audiofrog.com/wp-content/uploads/2018/03/A-Straightforward-Stereo-Tuning-Process-and-Some-Notes-About-Why-it-Works.pdf
I have time diff table, can I direct use tape measure to get the value. Use the table to get the ms and insert in T/A setting
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Discussion Starter #12
The only reference point you need is the speaker's voice coil. Simply measure (as accurately as you can) from a fixed point around the listening position (you can devise a rig on the head rest, or hang something from the head liner) to the center of the speaker. Typically there is a dust cap in the way, so add just a bit of distance to account for that. You are simply measuring from the voice coil of each speaker, to the fixed listening position. That's it, you're done with TA.
Use driver side head rest for reference right. After done adjust T/A, then start to set crossover or crossover first
 

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Use driver side head rest for reference right. After done adjust T/A, then start to set crossover or crossover first
Measuring to just the driver's headrest isn't accurate enough, pick a point that would be in between your ears while you are in your listening position. It doesn't matter which you do first, TA won't change.
 

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Discussion Starter #14
Measuring to just the driver's headrest isn't accurate enough, pick a point that would be in between your ears while you are in your listening position. It doesn't matter which you do first, TA won't change.
Okay, I will try it later. Woofer I havnt install, I have a 12 inch woofer but I consider underseat subwoofer or trunk woofer is better for ovarall. What your suggestion
 

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Okay, I will try it later. Woofer I havnt install, I have a 12 inch woofer but I consider underseat subwoofer or trunk woofer is better for ovarall. What your suggestion
I personally don't like underseat subs because they cause a lot of tactile vibrations. When you can feel the seat vibrate, the illusion of upfront bass goes away. But, there have been plenty of people who have done it with good success.
 

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Discussion Starter #16
I personally don't like underseat subs because they cause a lot of tactile vibrations. When you can feel the seat vibrate, the illusion of upfront bass goes away. But, there have been plenty of people who have done it with good success.
Okay, I will try trunk sub first because already have 12inch woofer x2, should I use one enough or use two.

Today I have done setting T/A using tape measure but when I open louder volume the sound is no good, is it my speaker problem or setting.

One more things, i found that my head unit have 5 band parametric equalizer / 7band graphic equalizer, should I use it?
 

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Could be a lot of things... Let's start with what don't you like about the sound? Too boomy, not enough midbass, too bright, etc.. ?
 

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Discussion Starter #19
Could be a lot of things... Let's start with what don't you like about the sound? Too boomy, not enough midbass, too bright, etc.. ?
I feel like not enough mid bass, when open louder, tweeter sound is cover all around. Fyi, my subwoofer hvnt install yet
 

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The good news is that you're supposed to tune your front stage without the subwoofer on so now is a good time to dial it in. The fact that when you turn it up and it loses its composure could mean that they have exceeded their limits or you haven't found their sweet spots. This is especially true of tweeters and getting them to blend properly. What components and amp are you running currently?
 
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