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Discussion Starter #1
Time aligned by ear at the crossover points for each driver. Woofers are in the stock doors. 2016 Crosstrek.

Questions:
1) Seems T/A for tweeters is almost useless b.c. move your head an inch and your out of phase, not to mention reflections. Is that right?

2) I did T/A at the crossover points. Did woofers and sub at 80hz, but then 170hz is completely out of phase. Adjust T/A and another spot is out of phase. Any way to deal with this issue?

3)Seems EQ is useless b.c. it only cuts and boosts. Is this because of reflections in the car and such? Would pointing the drivers close to on axis eliminate the problem (would need to make custom kicker pods)?

Thanks.
 

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Time aligned by ear at the crossover points for each driver. Woofers are in the stock doors. 2016 Crosstrek.

Questions:
1) Seems T/A for tweeters is almost useless b.c. move your head an inch and your out of phase, not to mention reflections. Is that right?

2) I did T/A at the crossover points. Did woofers and sub at 80hz, but then 170hz is completely out of phase. Adjust T/A and another spot is out of phase. Any way to deal with this issue?

3)Seems EQ is useless b.c. it only cuts and boosts. Is this because of reflections in the car and such? Would pointing the drivers close to on axis eliminate the problem (would need to make custom kicker pods)?

Thanks.

TA is simple, set it based on the physical distance of each speaker, that's it. There's no need to complicate it further, carefully measure the actual distance from each speaker to the listening position, and use those numbers.

For high frequencies we do not use phase to localize sound, for the exact reason you mentioned. Moving your head even a half an inch would change the phase, so we have evolved to localize high frequencies via amplitude, not phase. It's still worth setting the TA on tweeters though, because we do still use phase to localize the lower frequencies.

What's the problem with EQ? Cutting and boosting is what an EQ does, I'm confused. EQ is VERY important in a car, because of how crappy of environment it is. It's highly reflective, and asymmetrical.
 

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Discussion Starter #3
TA is simple, set it based on the physical distance of each speaker, that's it. There's no need to complicate it further, carefully measure the actual distance from each speaker to the listening position, and use those numbers.

For high frequencies we do not use phase to localize sound, for the exact reason you mentioned. Moving your head even a half an inch would change the phase, so we have evolved to localize high frequencies via amplitude, not phase. It's still worth setting the TA on tweeters though, because we do still use phase to localize the lower frequencies.

What's the problem with EQ? Cutting and boosting is what an EQ does, I'm confused. EQ is VERY important in a car, because of how crappy of environment it is. It's highly reflective, and asymmetrical.
You recommend that I not use the by ear technique that involves putting one driver out phase, finding where it cancels, etc.?

Sorry, I did not word my problem very clearly:
Even after EQing (using the method just mentioned) I find that some frequencies are still out of phase. I know this because it I flip one driver's phase and the sound get significantly louder. If I then adjust T/A to make that frequency in phase, another frequency will be out of phase. It seems I'm just chasing my tail trying to get the phase right for all frequencies.

My observation is that EQ is not able to fix these frequencies where phase is off. By just cutting one driver, it increases volume of the other only because there is less cancellation occurring, which doesn't seem to solve the problem.

My question is, is there a way to fix this issue or am I going about it wrong?
 

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You should not be using TA to adjust anything except arrival times. That's all it's for. If you set TA based on actual measured distance, then you are done. Once the driver is in phase, it's in phase. Any issues that you have with specific frequencies after that need to be fixed with L/R EQ. If you can't EQ the left and right independently, then you can't fix the issues.

Since phase is more important at lower frequencies, and amplitude is more important at higher frequencies, TA is very important for you mids, and L/R EQ is very important for tweeters.
 

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I hope you are time aligning for a position, measuring to either your nose or ear somewhere close to where you can ad or take a cm or so.

Once that is done, you are not done, depending on what tracks you use also, they need to be approved tracks for tuning and, you still need to reduce output levels on the left side to place the stage or center it, just TA won't fix everything, you still may have a stage closer to the steering wheel, and then you still need to EQ, cutting on on one side, also. If you don't plan to stay put in one position, you will experience issues if you are very picky, I did mine by ear and even though it's not perfect it's good even during driving and reclining the seat a bit.

Some people find the point or tune with the seat position that won't use while driving.
 

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You recommend that I not use the by ear technique that involves putting one driver out phase, finding where it cancels, etc.?



Sorry, I did not word my problem very clearly:

Even after EQing (using the method just mentioned) I find that some frequencies are still out of phase. I know this because it I flip one driver's phase and the sound get significantly louder. If I then adjust T/A to make that frequency in phase, another frequency will be out of phase. It seems I'm just chasing my tail trying to get the phase right for all frequencies.



My observation is that EQ is not able to fix these frequencies where phase is off. By just cutting one driver, it increases volume of the other only because there is less cancellation occurring, which doesn't seem to solve the problem.



My question is, is there a way to fix this issue or am I going about it wrong?
I would not do anything more than measure for your t/a then maybe tweak it a tiny bit to facilitate blending at the mid/tweet xover point. Anything phase related outside of the xover region should be fixed with eq or installation changes.
 

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Setting time alignment is the *easiest* step of tuning. You have a tape measure, dont you? Use it. Doing it by ear leaves sooooo much room for error.
 

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Figure out where the middle of your head is when you're in your listening position, use some string, a washer, and a piece of tape to hang the washer so that it falls right where the center of your head is. Use a measuring tape (or string) to measure carefully from the center of the speaker to the washer, be as accurate as you can. Plug those numbers in, and you're basically done.

You may need to adjust it a couple clicks up or down, but if you measure accurately you won't need to fiddle more than a couple of clicks.

That's it, TA is done. If you have issues with the staging after that, they need to be addressed with L/R EQ because they are amplitude problems, not phase problems.
 

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Discussion Starter #9
Okay. Yes. I measured for T/A this time... Thanks all. Instead of trying to deal with the phase issues using T/A, I just cut using eq to get the frequencies that are in phase at head position to be closer in volume to the ones that arn't. Normalized the FR graph of sorts. I guess I thought there was a little more to it.... Again, thanks all.
 

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Okay. Yes. I measured for T/A this time... Thanks all. Instead of trying to deal with the phase issues using T/A, I just cut using eq to get the frequencies that are in phase at head position to be closer in volume to the ones that arn't. Normalized the FR graph of sorts. I guess I thought there was a little more to it.... Again, thanks all.
thats how your supposed to do it
 

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I set my time alignment , now when move my head it sounds the same the image does not move around but it seams like my system is quiter. But I can hear everything. Is that normal?
 

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I set my time alignment , now when move my head it sounds the same the image does not move around but it seams like my system is quiter. But I can hear everything. Is that normal?
If anything, putting speakers in phase with TA would make them louder, not quieter. But, setting time alignment shouldn't make a big difference to the SPL overall. Most likely having speakers in phase is allowing you to tolerate a higher volume without them sounding bad. So, no they shouldn't be quieter, but being in phase may make them sound less abrasive, which maybe you're interpreting as being quieter.
 

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GIJOE I believe you hit the nail on the head. I went back out to my truck and played some more music and it is clearer then it has ever been. I think I was interpreting it as quiter but I am just not used to having the sound so evenly distributed.
 
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