How can Time Alignment possibly work?

[coachz]

If I have directional speakers in my front door panels (directional because they are producing signals over 80hz) then I do not see how time alignment will help in any way to create an open stereo soundstage and in fact will make things worse.

Lets say that my right door panel is 3ms behind the left in arriving to my ears at drivers position. If I delay the left panel 3ms, because of the directionality of the higher frequencies they will still appear to come from exactly where they are only later.

This cannot move the left channel image further left as desired and will actually smear the image even more. For a more dramatic effect, imagine the left channel being delayed by 1 full second and the slapback you will get but no shift to the left, just a delayed signal coming from the exact same position.

I would love to have a great stereo image in the drivers position but so far I do not see any possible way to achieve this.

I DO see how the time alignment will get things more cohesive by arriving at the same time just to be clear. But I don't see any way you can move the image to the left with directional speakers.

Please tell me I'm wrong and that I just don't get it. Thanks for your consideration.

John

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[ngsm13 5,000+ posts]

You're wrong, you just don't get it.

nG

 

[coachz]

How about explaining why ? You know like "impact my life " !

 

[ngsm13 5,000+ posts]

I'll poast when I get back from class...

nG

 

[Etac 10+ year member]

Lets say that my right door panel is 3ms behind the left in arriving to my ears at drivers position. If I delay the left panel 3ms, because of the directionality of the higher frequencies they will still appear to come from exactly where they are only later.

John

exactly, t/a doesnt fix where your sound comes from... it mainly helps cancelation issues, and can also help where it is centered, and help tweet/mid/subs arrive at the same time

think of it this way

two cars driving head on going the same speed - across your dashboard

they will collide in the middle.. the car on your left would pass you and hit the car to your right, which wont reach you...

delay the car on the left.. and theyll collide more in front of you..

 

[coachz]

so there does not appear to be a way to get a balanced stereo image where a guitar that is panned hard left will appear the same distance and opposite direction from a guitar that is panned hard right

 

[Etac 10+ year member]

you're taking the meaning of a soundstage the wrong way.. think of a concert.. do they angle the speakers for the people sitting on the left? no

the only possible way to achieve that (in a car) would be to put the speakers more to the side of you IMO... and would require a decent amount of tuning.. and wouldnt be considered a proper soundstage.. but could still sound good

i think alot of people that like rear fill would actually like it better with "side fill" as i like to call it, which would give more of a headphone affect... but ths would require alot of surgery on most cars, but i think this would be the type of sound you're looking for

where your sitting in your car, and your speaker locations.. its almost impossible.. unless you wanna completely forget about the passenger and put the right speaker right next to you/center of dash lol, or rip out your dash/front seats and move everything to the center of the car.. that will always be the dream, but then you wouldnt need T/A =] (or at least not as much)

 

[coachz]

Thanks for they great reply.

I was with you up to "but then you wouldn't need time align". I'm deducing that based on physics with directional sound (above 80hz), time align will do nothing for the stereo image other than make it more cohesive in it's current skewed state. So for me, time aligning will not get me the "headphone effect" i would like to get.

 

[LoggedOut 10+ year member]

 

[Torgus 10+ year member]

you only need time alignment in big theaters. your brain can't tell the difference between 1ms and 30ms. also seeing as how it's in stereo andeach speaker is producing DIFFERENT sounds it doesn't matter. look at the speed sound travels. zomg one speaker is3 feet farther away. ohhh noesss....

true story.

 

[Etac 10+ year member]

Thanks for they great reply.
I was with you up to "but then you wouldn't need time align". I'm deducing that based on physics with directional sound (above 80hz), time align will do nothing for the stereo image other than make it more cohesive in it's current skewed state. So for me, time aligning will not get me the "headphone effect" i would like to get.

basically

you only need time alignment in big theaters. your brain can't tell the difference between 1ms and 30ms. also seeing as how it's in stereo andeach speaker is producing DIFFERENT sounds it doesn't matter. look at the speed sound travels. zomg one speaker is3 feet farther away. ohhh noesss....
true story.

true your brain might not be able to tell the difference if the waves were reaching you cleanly... but the sound waves will reflect, cancel and interfere with eachother.. esp in a car... which your brain can hear (or not hear rather)

 

[coachz]

that is not correct, I do professional recording and i easily hear 3ms phasing. If I take your vocal and put it in both left and right channels and delay one by 3ms I can definitely hear it. Now do the same with a guitar or snare and do 15ms and you have a HUGELY noticeable change in sound. I fact I routinely do 15 to 25 ms on guitars and snares to get certain effects.

 

[coachz]

basically



true your brain might not be able to tell the difference if the waves were reaching you cleanly... but the sound waves will reflect and interfere with eachother.. which your brain can hear (or not hear rather)

You are talking about reflected waves and brain hears those separately from the initial direct sound.

 

[Etac 10+ year member]

You are talking about reflected waves and brain hears those separately from the initial direct sound.

well reflected are included in that.. but the bigger problem is sounds that are canceled out before you hear them.... like i said about the cars crashing.. now with sound waves.. that would be like 10000000 cars going head on at once... some might make it through.. some wont

let me guess OP, do you have your tweets up high?i like my tweets brought down so it kinda mellows them out, and makes the whole setup harder to localize, which should help, if im right

 

[Megalomaniac 5,000+ posts]

If I have directional speakers in my front door panels (directional because they are producing signals over 80hz) then I do not see how time alignment will help in any way to create an open stereo soundstage and in fact will make things worse.
Lets say that my right door panel is 3ms behind the left in arriving to my ears at drivers position. If I delay the left panel 3ms, because of the directionality of the higher frequencies they will still appear to come from exactly where they are only later.

This cannot move the left channel image further left as desired and will actually smear the image even more. For a more dramatic effect, imagine the left channel being delayed by 1 full second and the slapback you will get but no shift to the left, just a delayed signal coming from the exact same position.

I would love to have a great stereo image in the drivers position but so far I do not see any possible way to achieve this.

I DO see how the time alignment will get things more cohesive by arriving at the same time just to be clear. But I don't see any way you can move the image to the left with directional speakers.

Please tell me I'm wrong and that I just don't get it. Thanks for your consideration.

John

The adjustment in time arrival in the mobile situation is to "fix" the not having equal distances of your speakers, in essence manipulating the arrival time so it were as you were sitting in the center of the car. However its touch to gain width, and your staging wont be directly in front of you for the center, it will be in the center of the dash(generally).

If you play with t/a i suggest you have full active capabilities to control each driver.

if you want the center to be in front of you, you might sacrifice left channel integrity it would look something like this:

but if you can figure out how to gain more width on your left side you could end up like this and make it work:

but for most of us we are confined to the boundaries of our cars unless you gain a lot of pld by mounting in the kick and whatnot.

you well also want to level match each driver