He did that with a sub upfront. When we did my car I could have as much as 10MS added to mine. At one point we were playing around and added 12+ ms to the fronts and had the image half way out the hood, it was just like listening in a tunnel...
Printable View
You still have to remember that time allignment also plays the role of phase shifting. Delaying a sub can make it in total acoustical phase to the listener's position. I for one don't believe in the theory that says the sub (usually being the one further away from the listeners) should have 0 delay, and all the rest should tune to that. I'm not saying it can't happen, but it'll be due to the cabin size/shape, and the sub placing and angling.
Whatever works, man.
Somebody brought up this technique on Diyma and I tried it with fairly good success...at least it got me a good starting point:
1. Turn off all your channels except for the farthest driver and play pink noise
2. Starting with your next farthest driver, turn it on and reverse the phase 180°
3. Start adding t/a to this driver and listen for it to start cancelling out the original driver. In a perfect world, once the two drivers are in alignment, they should completely cancel each other out.
4. Once you've found the deepest trough, you are done. Switch the phase on this driver back to 0º and it should be in alignment with the source driver.
5. Repeat the steps with the next farthest driver.
As with any time alignment technique, it's a good starting point, but your ears will need to be the final judge.
I originally set T/A by ear using pink noise and familiar songs. I did something similar to what Al just posted and to the method posted on the first page using tones and a center image.
The result was promising, once I finally figured out that I needed to flip my passenger side full-range's polarity. I had a decent center image and strong left/right. But my center image was slightly to the left of where it should've been.
So last night for shits and giggles I redid all my T/A settings with a tape measure and then I confirmed/fine tuned those setting by ear. The results were so far from my original settings that its not even worth posting the numbers. The funny thing is that the image ended up about the same as before except my center was actually centered and I no longer needed to flip one of the midranges. In fact none of my driver polarities required swapping and my midbass felt more punchy. I also need to do a little more critical listening but it seems that I have more resolution in between center and left/right stage.
Sent from my Springfield XD with love!
I've seen numbers from each side on equalizer with sliders that were completely different ( no mirror image ).
But sound was very nice to my ears