rethink the stock tweeter location

So I originally made separate baffles for woofer & tweeter...


I had 2 thoughts: A) Toyota probably engineered that angled tweeter mount for superior imaging in the cab, and B) If there is a speaker grill there, sound should come out of that location. So the tweets went into the factory locations...


But the imaging was less than impressive. Details in the highs revealed exactly where the tweets were. It just didn't blend. So I mounted them in the optional coaxial configuration...


And what a difference it made! According to my perception, the sound stage is higher, wider, further away and much more even. Our local experts could tell you why this is the case much better than me, but it has a lot to do with the tweeters being more equidistant from the listener, as opposed to one tweet being right next to you and the other across the cab. This is why speakers in kick panels, while on the floor, can give the perception of music coming right through the windshield. If your separates have the option of being mounted coax, I would highly recommend you try it. If they don't, you might even try mounting them separately in the same lower baffle. You've got a 6x9 space to work with down there.

Another solution you might be interested in is where I put the crossovers. These Polk SR crossovers are HUGE and I'm out of space in the back. So they both went on a lifted platform under the passenger seat. It's elevated enough to let the AC vent blow right under them. My amp (JL HD900) is elevated in the same way under the driver seat.


Thanks for looking. I'll leave you with a gratuitous and unrelated shot of my sound deadening project.

 

Holy smokes man!... How much did all the sound proofing cost you?

 

about $200 for a 100sf roll which is exactly enough to thoroughly cover all the interior of a double cab - floor, back wall, 4 doors & ceiling.
http://www.fatmat.com/bulk/rattletrap/100.html

 

What type of tuning capabilities does your headunit have? I'm guessing your biggest gain was not that the tweeters are really in a better place, but that they and the midbass are equidistant from your ears. Also, both sets are now mounted on the same axis so it should be obvious that the sound appears to come from the same place.

Low mounting tweeters like that or kick panels really bothers me though if I'm being honest. I think that if you have some time correction capabilities they should me mounted up higher. Why use voodoo to trick your brain into thinking the tweeters are someplace you could ACTUALLY put them?

 

And nice deadening job. I bet that took an eternity. I would know.

 

HU is a Kenwood DNX 1720. No time correction capabilities, but I'm running the polks passive anyway so no use. The difference between the distance from my head to the stock tweeter location and from my head to the stock woofer location is less than 2 feet anyway, so would time correction even yield a detectable improvement? I'm guessing no. As to voodoo trickery - I don't want it to sound like the tweets are in the factory location. I want it to sound better than that. Some of the best mobile audio imaging I've heard has been in vehicles with separates in the kick panels. Thanks for the deadening props.

 

Two feet may not sound like a lot...but try making that a percentage of the lesser path

 

My Hybrid Audio speakers original came mounted together in coaxial format, and it REALLY didnt work for me. It was quite apparent that the sound had dropped in location. It also sounded like it lost some clarity in the higher frequencies that the tweets put out at lower volumes, presumably because of the location.

I had the seperated, and went to running them back in component function with the tweeters in the standard door location.

As always, YMMV, but the coaxial tandom setup didnt work for me.

EDIT: It would only be fair to add that Im really not an expert in fine tuning an audio setup, so Im not blind to think that the sound couldnt have been properly modified by a pro to improve its...balance.

 

Really? I know very little about time correction - the only time I've dealt with it was running sound at a pavilion concert where there were lawn speakers set up 50 yards past the mains. In a car... I just don't see it. What am I missing?

 

Thanks for the input. It may well vary quite a bit with speaker brand, amplification and personal preference. Glad you tried it both ways - that's all I'm asking.

 

Two ways to think of it from what I understand. Percentages and drawing a triangle help from what I can say. And let's say your closest speaker is 2 feet away and your farthest speaker is 5 feet away (right side of the car). That would make your farthest speaker 150% farther than the other! Doesn't sound so insignificant now right?

Draw yourself a triangle, I think it helps. Left vertex should be the left speaker and right vertex should be the right speaker. The third should be you as a listener. The further you are from the speakers the less it matters how equidistant you are from them. As you can see from the changing of the angles which would be minimal the farther away the listener is. Now move the listener very very close to the speakers. A small discrepancy in distance of the speaker changes the angles of the triangle considerably. I really hope that made sense. Sounded good in my head.

 

you also need to take account for the 90 phase shift on the driver side, and approx. a 45 degree phase shift on the passenger side, then account for the angle of the tweeters phase shift, and account for the distance when mounted seperately, and then account for the relative phase shift between those speakers, etc etc etc....

shall i keep going?

 

Makes perfect sense. You're talking about left/right correction. Before I thought you were talking about correction between woofer & tweeter independently on each side, which is why I thought I could make no use with my passive set up. Great explanation and I certainly could employ time correction if my head unit offered it. But I still feel that it's useless in a taco. First, proportion is irrelevant. The only thing that matters is the difference between distances because the speed of sound is constant. In your triangular example of a 2' vs 5' speaker distance, the difference is 3 feet. Yes, the farther rearward the listener moves the better the situation becomes due to the difference between the distances from you to each speaker decreasing. But imagine that same set up in a straight line instead of a triangle: One speaker is directly in front of you 2 feet away and another is directly past it at 5 feet. No matter how far rearward you move in order to get those distances proportionally closer, the same amount of correction is needed because the difference will always be 3 feet. Proportion is irrelevant. Back to your example of a triangle with the L speaker 2' away and the R speaker 5' away. The Difference again is 3 feet. The speed of sound being 1125ft/sec, the audio from the right speaker will reach your face 0.00266 (repeating) seconds later than the audio from the left. I'm no scientist, but I don't think any human could perceive that difference. And if we COULD hear it, and corrected for it, the delay from the passenger seat would be twice as bad since we would have corrected in the opposite direction.

 

Wow. You're smart. Yes, keep going, please.

 

no not really smart at all, just learned alot about what happens in a car when you mount speakers at different angles. Many different ways to come to the same goal......... EXCELLENT SOUND. I worked for a speaker company for a while, learned alot about on-axis and off-axis responses. And also efficiency. X-over points and slopes of said x-over point make big changes too. Beyond that it is even more rediculous. Competeing does that to a person, really it does. I spent so much time building and changing things, i realized that i just want to enjoy my music to the fullest extent, not take over a year to build it.

If that makes any sense.

 

i see what you are getting at, and this equation would work if you had 1 ear in the front of your face....

however because of 2 ears, and our perceived (learned habit) of focusing with sound, our brain takes cues from both ears to decipher the "position" of that original sound. Our cabs are so small, that moving your head 3-6 inches in any direction, changes that perception, and you have to then take care of acoustic reflections, and lulls and spikes in the acoustic field. Honestly the vehicle is one of the worst things to EXPECT live performance sound from. You are always biased left or right. Changing it to sound good from either side, adversely effects the other. Hence a happy medium needs to be attained to make all happy.

 

good photoshopping, kinda funny actually.

 

Jason, do you actually think that phase on a tweeter matters much? I know (and can verify) that switching the phase on a midbass or sub changes everything but since tweeters play so high I've never found a phase switch on them to do much of anything.

 

the only time i "saw" a difference was on an RTA. other than that, hell no....i could never hear the difference, however you can "see" it when you analyze it. I would venture to say they are very few people who could....even in the optimum environment...most people (including myself) would be hard pressed to actually hear it. I used to have my own Audiocontrol RTA and used to test things at random times. There are so many variables it gets rediculous. X-over points, slopes, then overlapping xover points and the shelving it creates. and so on and so on...

I ran HLCD (horn loaded compression drivers from Image Dynamics)for the longest time. Now i just want to listen to my tunes and enjoy them. I did the whole SQ thing, and while it was fun, im just over it now. I think my SPL days have finally taken their toll on my ears, i have noticed slight variations in sound and i have hearing tests 2 time a year, and 4k-6k seems to be my problem area.