set time delays correctly! measure from the grid or from the bottom of the cone?

[surreal89]

Hi everyone.
my question is already in the title!
When making measurements to set delays between the speaker and the listening point, should the measurements be taken from the grille to the listening point? or would it be more correct to remove the grilles and take measurements from the listening point to the base of the speaker cone without the grille?

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[Doxquzme Premium Member]

You can remove the grill if you want to, I would estimate the additional distance. Without a mic it's still an estimate and you should be close enough to be in the ballpark as much as reasonably expected. Easy enough to poke a piece of pasta like plastic or 20 gauge wire through until you lightly tap the dust cap without ruining anything, add the length, good to go.

 

[ThxOne Premium Member]

That's all I have done when I had factory grills on the door panels, I just measured from the back of the grill to the speaker cone and added it to my distance measurement. I used a piece of straw from a broom and went through the grill until it touched the cone, then measured the straw. Simple, effective.

 

[dragon.breath 10+ year member]

I would not spend huge amounts of time trying to get the measurements down to the millimeter. Just get basic measurements down to an inch or two. The reason I say that is that I have set up time alignment in a few cars over the years and I have had to tweak every one of them away from what was measured to make it sound right.
I believe that it is because of all of the sound reflected surfaces in a car ( like the windows ).

 

[Buck 5,000+ posts]

I think it would make more sense from the cone, technically.

I wonder if time alignment even matters if you have enough bass to flex your doors, like there's no telling where your speaker actually is at any given time. I've done TA on my systems before but the way I listen to music seemed to make it not matter.

 

[winkychevelle 10+ year member]

I think it would make more sense from the cone, technically.

I wonder if time alignment even matters if you have enough bass to flex your doors, like there's no telling where your speaker actually is at any given time. I've done TA on my systems before but the way I listen to music seemed to make it not matter.

Yes time alignment still makes a difference with centering the sound stage. Midbass will never exist though. You just can't get enough midbass spl to keep up with the subs. I think mine measure out at Mike 115db with a USB mic with the midrange and tweeters 200hzand up 10-12db lower but subs can easily exceed 130db and at real spl levels you'll never get enough midbass in front of you.

Now I e thing I hate is when ever sound sounds like it's coming from the closest speaker makes me feel dead in the opposite ear.

 

[nauc 10+ year member]

id do what Dox said

 

[surreal89]

Yes time alignment still makes a difference with centering the sound stage. Midbass will never exist though. You just can't get enough midbass spl to keep up with the subs. I think mine measure out at Mike 115db with a USB mic with the midrange and tweeters 200hzand up 10-12db lower but subs can easily exceed 130db and at real spl levels you'll never get enough midbass in front of you.

Now I e thing I hate is when ever sound sounds like it's coming from the closest speaker makes me feel dead in the opposite ear.

thank you so much for your answer
Is it normal that when you set delays, not only the speakers located on the driver's side are automatically delayed, but also those on the other side?...
I thought that once the measurements were taken the system would only delay the side closest to the listening point!
perhaps this happens because I also inserted the sub's measurements into the DSP, and therefore each speaker delays taking into account the one furthest away, in my case the sub...
therefore it is normal that the side opposite the listening point is also slightly delayed.
One thing I noticed though is that the voice is not exactly in the center of the dashboard, but is slightly slanted towards my listening side!
does centering the scene mean having the voice perfectly central in front of the eyes??
or does it have to be in the center even if my driving seat is on the left anyway?
I took the new measurements from the bottom of the cone and I have to admit that everything has gotten worse, now despite the levels, phases and intersections being laid out perfectly, a lot of the scene now seems to have moved only to my driving side.
so I restored everything to how it was before.
the scene is central, but as I said above it tends 5/10% towards my driver's side.
To correct this problem should I increase the driver side speaker delays or decrease the opposite side delays?

 

[winkychevelle 10+ year member]

thank you so much for your answer
Is it normal that when you set delays, not only the speakers located on the driver's side are automatically delayed, but also those on the other side?...
I thought that once the measurements were taken the system would only delay the side closest to the listening point!
perhaps this happens because I also inserted the sub's measurements into the DSP, and therefore each speaker delays taking into account the one furthest away, in my case the sub...
therefore it is normal that the side opposite the listening point is also slightly delayed.
One thing I noticed though is that the voice is not exactly in the center of the dashboard, but is slightly slanted towards my listening side!
does centering the scene mean having the voice perfectly central in front of the eyes??
or does it have to be in the center even if my driving seat is on the left anyway?
I took the new measurements from the bottom of the cone and I have to admit that everything has gotten worse, now despite the levels, phases and intersections being laid out perfectly, a lot of the scene now seems to have moved only to my driving side.
so I restored everything to how it was before.
the scene is central, but as I said above it tends 5/10% towards my driver's side.
To correct this problem should I increase the driver side speaker delays or decrease the opposite side delays?

Time alignment is used to delay every speaker closer than the furthest to have the sound hit the listeners ears at exactly the right time. If this is true the image should be about eye level centered with your head. Height of stage is often limited by speaker locations but it's less important to me that centering left and right.

Keep in mind not all music is recorded with a center some music the sound stage wanders left and right.

Time alignment can be close to perfect and you still have phase off a bit. But phase can't be easily adjusted with every dsp only some have the ability to unwrap it or at the very least use allpass filters for severe nulls.

But getting the phase between the subs and the midbass is the single most important thing for upfront bass. Or that kick in your chest feel. Some people get lucky with install locations but a dsp can fix a lot of that these days.

Eq helps a lot when you can do each individual drivers since it lets you smooth out the frequency response but excessive eq can cause issues as well but to a lesser extent.

Personally if you aren't running full active I wouldn't consider a dsp beyond the one built into most radios