Time Alignment 101

[@ErinsAudioCorner]

My online time alignment calculator: www.erinsaudiocorner.com/timedelaycalc/

[@timmothy19]

Thanks for sharing your knowledge with us. You explained everything and presented it very well. Need more channels like yours. Thanks again. Donation sent.👍

[@acoustikworld2201]

I am very grateful for each video you upload, I have learned a lot! is possibly the best audio channel on all of KZbin!

[@ErinsAudioCorner]

That’s great to hear that kind of feedback!

[@ytnimal]

Hi Erin, 1. My mids are in doors and tweeters are in sail panels. I measure from the grill of the door pad to the middle of the headrest? 2. Everytime I do this the image is right in front of me rather than phantom center. Have checked everything and the polarity is right and slopes are 24db. What could be the issue? Have tried the same in friends cars and its always driver side rather than phantom center.

[@xXAlciel]

I have an Alpine 507, and I have the option to use inch, ms, and cm. When I get the measurements I plug them into the calculator and calculate in ms. When I put my 507 into ms measurement the sound has no center channel. I really don't know what I am doing wrong. I can't tell if my head unit calculates the zero point or if I have to calculate that and then put the numbers in the calculator. Any idea if my head unit does the zero point? I also am not active, I have passive coaxials currently, however this will change very soon.

[@ginodavis]

Hi is there a option to include rear speakers?

[@tcaudiomute]

to be honest I love using the delay mode. Its magic

[@califmike2003]

Followed your calculator formula, when i put the values in my headunit dsp, it giving me cm measurements when i enter your values, , but when i convert those cm values its way off from what your calculator is saying to do, what should i do ?

[@danielsie2969]

Hi, i would like to ask, for the 2 way system, the rmb & lmb is disabled. Only rmr & lmr ?

[@alyousuf]

if after the adjustments, the time of arrival to both ears is identical, and the levels to both ears are also identical, then shouldnt the new phantom center be right in front of you and not in the center between the two loudspeakers. Sort of like a headphone, same amount of delay and level from both sides makes YOU the center. This has been confusing me.

[@audioexpertsllp1618]

Hi, I have been watching many videos on the subject, but yours is very simple & detailed. Let me visit your website also.Thabks Sir

[@JoshM7]

Very cool tool. I'll have to come back and use this when I do some upgrades to the car. I plan on replacing my front speakers and adding a tweeter to the factory location. Currently just using some coaxials. They'll be ran on the same channel with a highpass for the tweeter and lowpass for the midrange. (Both at 4,500Hz) I might use a Lpad to dial back the tweeter a little if it needs it as well. Since they're not individually DSP controlled would I enter the same distance for the tweeter and midrange based on the midrange distance? It's an 03 Buick Regal so the tweeters are on the door not too far above the 5.25" speakers location.

[@ErinsAudioCorner]

Yes, in this case it makes more sense to use the midrange distance for setting T/A.

[@leoadam5410]

Hi Erin, will this alignment calculator work on right hand drive?

[@PeteSHLeong]

Thanks for the great sharing. Got a question, what if in the case for a BMW car where the midbass is located under both front seat, what value should we use ?

[@variety5061]

Honestly, I got rid of them. It's a poor location for a very important driver.

[@anirudhpanwar6202]

whats is LT,LMR ,LMB etc

[@socketsocket2763]

Love your vids and your time alignment calculator. would be great if there was an option to select right hand drive or left hand drive for us RHD drivers in Australia and UK ;)

[@MP_Soundbox]

I just learned about this subject yesterday, but from what I've absorbed so far, wouldn't one simply reverse the numbers? Measure and then change the negative to positive. You can choose any listening position and measure, calculate from that point.

[@uptobatentertainment]

When I enter all the distances in my Helix DSP SW the result is the stereo image pulls to the right. In songs I know instruments that are panned left sounds centered and vocals sound to the right. This happens when I use time alignment to my subs ( farthest away ) or no subs, just the mids and highs. Both do the same to the stereo image. I’m on a Helix DSP.3 but this also happened with my previous DSP Edit: Im using distance mode in the same SW and did not use your website, used a tape measure.

[@ErinsAudioCorner]

If you're entering the distances as distance in to the Helix software correctly, my hunch is something is out of phase.

[@uptobatentertainment]

Erin's Audio Corner everything is wired at the amp correct but I’ve never seen behind the door panels or A pillars to check the wiring the original installer I hired did. He did wire my subs out of phase so it could be a possibility.. I seem to play pink noise decently flat and don’t have any huge dips in the signal but that was using Apps on an iPhone ( iPhone mic goes down below 30Hz ) I have a measurement mic coming. When I entered the distances subtracted from the farthest speaker’s measurement ( subs ) in the SW, the stereo image sounds much more realistic... However the Helix manual says to enter the tape measured distances & that’s what skews the image ( so did the Hertz DSP ) So am I doing it wrong? I know what the manual says but it also says to then adjust by ear if it sounds off. Do I enter the actual tape measurements in the distance mode or the subtracted measurement from the farthest speaker? I guess I will have some more car to tear apart.. Smh... Thank you

[@uptobatentertainment]

Erin's Audio Corner will flipping the phase in the SW provide the same result as taking the door card off and fixing the wiring if it’s out of phase?

[@ErinsAudioCorner]

@@uptobatentertainment You need to make sure that the left and right midbass are acoustically in phase and that the subwoofer is in phase with the two midbass drivers. Typically this means that polarity of the drivers are all the same, but subwoofer to midbass phase is usually not 0 or 180 degrees that a polarity swap would net you. Instead the subwoofer to midbass phase alignment is often found to be at some increment between 0 and 180; for example, maybe 25 degrees. You would need a DSP with variable phase to correct for this.

[@uptobatentertainment]

Erin's Audio Corner ok excellent thanks for the help! I can adjust the subwoofer phase is the DSP PC Tool SW in 11.25 degree increments. My Zapco ZII bass amp has a variable phase from 0 to 180 as well but I will probably use the SW. I ordered a UMIK-1 measurement mic as well. I will play some tracks I know well and flip the phase in the SW to see if the mids cancel out, sound the same, or sound better lol. Then when the measurement mic gets here I should be able to find out exactly. Enjoy your Memorial Day weekend.

[@izudeen]

hi.. how do i set TA for rear channels? I have only 4-way channel DSP (FR,FL,RR,RL) with 2way component infront and coaxial behind..

[@natskar]

TA for the distance for the fr mids and rears then. That’s what I did and it’s fantastic

[@viko_drapak]

I would be interested in how fine-tuning the time delay after having the delay set by the distance works, like how much ms at which particular frequency range can change the phase of two drivers. Also, I have an Audison DSP which doesn't allow me to make groups or links when doing this time alignment fine-tuning, any suggestions on how to proceed when doing one by one driver?

[@ErinsAudioCorner]

You should only need to fine tune the delay if things sound "off". In a car the environment is a bit tricky to properly measure the distance (i.e., speaker behind door panel, etc). In a home it is much more straightforward and should be unnecessary to make manual adjustments after the fact. Just getting that out of the way. Time delay is a full spectrum shift so the only frequency-basis you would experience would be due to different reflection times due to the different path lengths from speakers to various reflecting points. But your goal is to align the direct sound with a tape measure and that should get you in the ballpark. You can make manual adjustments if the tape measure isn't precise enough (again, speaker behind door, etc). Alternatively, you can use a loopback-based measurement setup which will tell you the actual time of arrival of the impulse and then you would use this to align the impulse peaks from all the speakers.

[@Nanorisk]

So, if I want all 4 seats in the car to have a global center stage like in a private theater, I should assume the listener is sitting on the glove box, right? My car has a center speaker and c pillar speakers, along with door speakers.

[@ErinsAudioCorner]

You’ve got a center channel. You don’t need to do any time alignment other than aligning sides of speakers. Meaning, align tweeter with mid on left and on right. Even still, not all 4 seats will have the same response. But a center channel is the best way to get toward that goal.

[@Nanorisk]

@@ErinsAudioCorner I tweaked some delay settings and it is half decent fornthe front seats. Thanks! I now have another question: should I even attempt to add a center channel tweet in the glove box that faces the rear passengers? The reason being that during the tweaking for the rear seats, what I felt was that the mid tweeters are way too far to the front. I have added front firing C-pillar speakers at the factory location, which mitigated the left and right channel issue somewhat, however the center channel is still way to far, hence sounding quite hollow if the mastering is not done right.

[@Masterdebator881]

When using the “crossover” portion, do you recommend using the electronic crossover point or the actual acoustic point? Example; a midrange with electronic xover hp at 100hz@24db, but measures 130hz@24db on rta.

[@ErinsAudioCorner]

I think it would make more sense to use the acoustical crossover point. I say if you're going to try it, though, to try both. Feel free to let me know your results. Like I said in the video, that's one of the more "experimental" type things I included in the site. I don't think it's entirely necessary but might be a good alternative to not having variable phase.

[@Masterdebator881]

Erin's Audio Corner Cool! I will try both ways and see what works best. Will report back...

[@darieng619]

I have an Alpine DSP with component 6 x 9's in the door of my 2018 Maxima. The woofers are in the front door panels and the tweeters are in the dash. Both speakers are connected using a single channel. How do I pick the distance for these 2 speakers? Measure them both and average the distance between the 2? I.E. the tweeter is 48" and the woofer is 50". Set the distance to 49" ?

[@ErinsAudioCorner]

I'd probably go off the distance of the woofers.

[@darieng619]

@@ErinsAudioCorner OK. Can I ask why?

[@ErinsAudioCorner]

@@darieng619 we differentiate sounds coming from our sides based on time and amplitude. However, the frequencies we base these on are split around 1-2kHz. Below this we predominately locate based on time of arrival. Above, amplitude. Therefore, time arrival is more important when it comes to low-to-mid frequencies. You can learn more about this by searching for "interaural level difference" and "interaural time difference".

[@darieng619]

@@ErinsAudioCorner I think you were right. I tried it averaging the distance first and the sound seemed to be coming from about the middle of my dash, (like where the head unit is). I changed the distance to be where the woofers are and it sounds higher up now. More like on top of the dash. Thanks for the help.

[@hassannasir90]

Hi Erin, The best video for Time alignment. I have Helix DSP 3 with Focal K2 in my truck. However, I use both driver and passenger seat in my car. Should I do time alignment? If yes, then what location?

[@eustahijelifetips]

center?

[@AnasSuhaimi]

my guess is to create 2 profiles, and then choose the seat you sit on. Say, profile A with measurement between speakers and driver. Profile B, is for front passenger. When you're the one driving, choose profile A. When someone else is driving, and you're in the front passenger seat, choose profile B. Fuck the other people, it's your car, you're paying for it. Hell yeah. If you dont tell your wife about it, she wouldnt know and not gonna ask for profile B when you're driving. The only time you set the right profile for her is when you're seeking her approval to finance the system, but keep it discreet.

[@matt.246]

It says sub lp when I select the regular way. So do I enter sub low pass or is it a measurement

[@ErinsAudioCorner]

Just ignore that then.

[@zorhis1996]

for the subwoofer do u meausre to the middle of it or the closest part to u

[@ErinsAudioCorner]

For a subwoofer it doesn't really have to be super precise because the wavelength is so long. But, with that said, I'd generally saying the dustcap is adequate.

[@zorhis1996]

@@ErinsAudioCorner ok thank you , im doing my custom computer system and I have a 21" driver sitting right infront of me to my left

[@zy1010]

According to my understanding, if you set the subwoofer crossover point below 65hz, I will be non directional, please correct me if it is wrong

[@yaominglin9798]

after finish TA, when i want to move stage. why i should adjust level +1.25db/-1.25db ? big thanks

[@ErinsAudioCorner]

because time delay and level matching are both needed to steer the image. Realistically, the stage center should be approximately in the middle of the dash but some people simply prefer it to be at a different location; thus the inclusion of the additional offset.

[@yaominglin9798]

@@ErinsAudioCorner if i use app to measure the SPL of each speaker. according 1m decrease 6dB， should i do leveling SPL first or TA？

[@Nightjar726]

Can you time align half decently for the driver and passenger?

[@ErinsAudioCorner]

No.

[@Nightjar726]

@@ErinsAudioCorner so what do you do as a ‘ compromise ‘ for passenger and driver in a tuning profile if you don’t mind me asking? I got the driver side all nice and time aligned. Thanks Erin. Your channel is getting seriously good.

[@ErinsAudioCorner]

@@Nightjar726 have a compromised setting with no time alignment.

[@Nightjar726]

@@ErinsAudioCorner just zeros for delays?

[@ErinsAudioCorner]

@@Nightjar726 I mean, there’s not really much you can do here other than maybe trying to align speakers on their same sides. But left/right alignment won’t do anything other than make the sound better for one side. But not both.

[@berkantopaloglu4420]

Thank you bro , ı am looking for this shıt evrywhere 😅

[@tfunk1829]

Measure with the doors open?

[@ErinsAudioCorner]

tfunk 182 nooooo. I just had the doors open to get light inside the car.

[@tfunk1829]

Erin's Audio Corner ok I saw another video that was similar and thought maybe I was missing something.

[@risingrocksoundsysteminc.8673]

What is RT

[@ErinsAudioCorner]

Right tweeter

[@zorhis1996]

my subwoofer says 0 but my speakers say 2.33 , is that correct ?

[@ErinsAudioCorner]

If the subwoofer is the furthest speaker away, yes.

[@zorhis1996]

@@ErinsAudioCorner ok thankyou

[@ccy1986]

what is lmr/lmb/rmr/rmb?

[@ErinsAudioCorner]

Left Midrange Left Midbass Right Midrange Right Midbass

[@sonicgauge1]

Thank you!

[@pocket5s1]

First!

[@ErinsAudioCorner]

2nd!