HardHitter

iTrader: (4)

I'm going to do components into my FD and I am trying to find a good place to mount the tweeters. I'm thinking maybe on the pillars or if I can find a good spot, maybe on the door panel, just scared of cutting things up. It will be flush mounted.

Yes I have done a search lol

HardHitter

iTrader: (4)

Bump!

AustinCustoms

The A pillars would be good. The door works too, but that's a little too close to the listener. If you've got an extra DIN space, you could mount them there too.

CCarlisi

The shop Wael used had them firing at the windshield glass and reflecting back at the passengers.

plaguepunx

iTrader: (8)

I had them in the triangles on the dorrs and the imaging was horrible so I drilled some stuff and put them next to the woofers in the doors.

apex_sideway

Can we see pics?

FDNewbie

iTrader: (10)

I think you had them facing the occupants (driver/passenger). It's too harsh like that. You want the tweeters facing each other (as if they were firing at another). It'll solve that prob. That's how I have mine.

Chris, where? Were they mounted on the dash? Do you have pics?

purerx7

iTrader: (61)

I am in the process of making custom sails off the triangles on the doors. Heres a step by step tutorial on how to do it. http://www.caraudio.com/vb/showthrea...687#post811687

It starts at post 96. This would be the ideal setup, ofcourse next to mounting them on your dash and having the wave bounce off the windsheild. I have listened to both ways and honestly like the way the sail looks and it sounds exactly the same. Heres a pic of the sail that he did, although I think it needs more work you can get a general idea.

HardHitter

iTrader: (4)

I just don't want to cut into my doors and find out that it sounds like crap, that's the reason why I am trying to find the spot to do it right now.

DamonB

I put mine in angled surface mount pods attached to the triangles. They fire towards the occupants and were easy to do. The pods are bolted to the triangles with small screws.

Speakers are designed to be heard on-axis. That means the speaker should more or less face the listener and this is especially true with tweeters. Midbass and subs can get away with the listener being farther off-axis.

Install everything but the tweeters themselves. Then connect some long speaker wire to the tweeters and get a couple golf ball sized pieces of putty. Spend some time sitting in the the car listening to familiar music and move the tweeters around to different locations; just mashing them temporarily into place with the putty.

DamonB

The playback of recorded stereo music requires the listener to be within the soundfield of both the left and right channels. Mounting both tweeters in the DIN space will never accomplish that and is still a stupid idea.

purerx7

iTrader: (61)

Shouldnt the tweeter be aimed at the opposing listener? So the tweeter on the passenger side should be aimed at the drivers face... Than obviously the drivers side would be amied at the passengers face, creating symmetry? Or maybe it is, kind of hard to tell from the pic...

DamonB

In the car environment this normally turns out to be coincidence of many installs rather than a rule that is to be followed.

Stereo sound is recorded in a specific way so that when played back through properly placed speakers you get imaging. It's very fundamental. If the speakers are not placed correctly you don't get any imaging, you merely get noise coming out of two speakers (like placing a stereo pair of tweeters right next together in a DIN opening). Fact is you would like the listener equidistant from every speaker but that's usually impossible to acheive; especially in cars. Because it's so impossible to acheive in cars the imaging is poor compared to a well designed home system that doesn't have to live with as many compromises in placement.


Quickest info I could find that describes how all of this is truly fundamental:

True stereophonic sound systems have two independent audio signal channels, and the signals that are reproduced have a specific level and phase relationship to each other so that when played back through a suitable reproduction system, there will be an apparent image of the original sound source. Stereo would be a requirement if there is a need to replicate the aural perspective and localization of instruments on a stage or platform, a very common requirement in performing arts centres.

This also means that a mono signal that is panned somewhere between the two channels does not have the requisite phase information to be a true stereophonic signal, although there can be a level difference between the two channels that simulates a position difference, this is a simulation only. That's a discussion that could warrant a couple of web pages all by itself.

An additional requirement of the stereo playback system is that the entire listening area must have equal coverage of both the left and right channels, at essentially equal levels. This is why your home stereo system has a "sweet spot" between the two loudspeakers, where the level differences and arrival time differences are small enough that the stereo image and localization are both maintained.

purerx7

iTrader: (61)

^thanks, that helped clear up a couple of things

rynberg

Damon, in some cases I would agree with Ramy that the tweeters should be aimed so that the listener is off-axis. Some car audio tweeters seem to be balanced to have flat output off-axis -- apparently the manufacturer assumed that most people would not be directly on-axis and balanced their tweeters accordingly. Whether or not you agree with this practice, it does happen. Personally, despite MB Quart's reputation, I think they must design their tweeters for off-axis listening -- either that or they are following the German loudspeaker tradition of having enough treble to sear a steak.

FDNewbie

iTrader: (10)

Hold up...all I read was "I would agree with Ramy." Did I read that right?!

AustinCustoms

It sounds stupid, but believe it or not, it works. I did it in a civic because the owner did not want to cut into any of the factory panels. I spread them out as far as I could, and faced the left one at the passenger, and the right one at the driver. It doesn't sound amazing, but for not having to cut into any panels, it sounds good.

DamonB

It doesn't work. It makes noise but completely fails at stereo reproduction.

This install forces each listener to only hear a mono type signal from the tweeter. The driver essentially hears both tweeters as a point source in his right ear and the passenger hears them as a point source in his left ear. There is absolutely no stereo imaging at all from the tweeters. All this install does is make noise.

Somewhat off axis? Yes. Nearly 90 degrees off axis? Helllllllllllll no. I challenge anyone to show me a frequency response graph of any tweeter that looks even somewhat decent at 90 degrees off axis. I'd be surprised if you could even find one that was measured out to 90 degrees; nobody bothers to measure that far off axis. Rynberg will know why.

If the two tweeters are directly facing eachother and are positioned well in front of the listener's head the listener is not even in the soundfield of both tweeters; he's hearing "leftovers". In an FD the driver would hear the right channel at a higher level than the left because he's so close and so far off axis to the left channel (vice versa with the passenger). You could easily prove this with a test tone and a $40 sound meter.

purerx7

iTrader: (61)

^ well than what would be the ideal positioning of a tweeter? On the dash and off the windsheild? That would be a pita to make, im in the middle of positioning my tweeters, so apparently you cant do it the way i figured.

DamonB

The true ideal could only be accomplished in very few cars. In any car it's best to give up on ideal and just do the best you can with what there is to work with IMO. My point was that if using the triangles as a mounting point the tweeters should be angled towards the listener(s) rather than directly facing eachother and firing across the cabin. Pointing the tweeters toward the listener doesn't leave the listener so far off-axis and this is always good.

A loose analogy would be to think of the tweeter as a flashlight emitting a beam of light that sweeps out in front of it. The better job you do of focusing that beam on the listener the stronger the stereo image will be. If you looked at a flashlight from 90 degree to its side you could still certainly observe light, but the quality and strength of that light absolutely sucks compared to what you would observe as the light is rotated to point more directly towards you. If you're 90 degrees off-axis to the light you're only observing the weakest portion of the beam and the strongest portion of the beam with the most energy is now focused somewhere else and bouncing all over the inside of the car. At the very least it's inefficient. In the real world you're now dealing with all sorts of terrible reflections and from your listening position the reflections will over power the source. You want the principle sounds you hear to be the source, not reflected artifacts of it.

Admittedly if your source can't acheive a certain level of sound quality to begin with it won't much matter.

purerx7

iTrader: (61)

Ok i understand, but taking your flash analogy, if you have the flashlight and have the tweeter fire accross to the other side you are still focused on the listener. Now, your point, I assume, is that it looses imaging the longer it takes to reach the listener. But, in your way wouldn't you have a very weak center stage? My system is capable of acheiving the best, it consists of
Pioneer ODR h/u and processor
Monitor 1 comps ( comparable to the top of the line dyn's if not better)
Diamond d7 amps
Obviously im not working with shabby equipment, im trying to get the most out of it. Than fine tune it with the h/u once the tweeters are positioned.

DamonB

Not in the FD. The tweeters would be well in front of the listener's head. His ears are no where close to being within their soundfield unless he poked his head through the steering wheel.

Time doesn't matter as long as it's equal (whole 'nother problem in a car). My point was that the listener is in the weaker outskirts of the sound field and the strongest sound he hears will actually be reflected sound that is now colored. It has to be; he is in no position to hear the sound directly since the left tweeter is pointing 90 degree away from him and is about 18" out in front of his ears. the listener is terribly off-axis from the speakers and this is always bad; especially with tweeters since their frequency of the audio spectrum is more directional anyway.

Here's the first response graph I could find. This is typical of all speakers. Notice how horribly quick the response from the tweeters plummets as you get off axis. Do you truly realize how HUGE a -10 (or -20!) dB difference in response is? A mere -3dB difference in response means that the sound is already only half as loud!!!



It would have the strongest stage for the listener that mounting location is capable of producing. Firing the tweeters directly at eachother across the car could make a strong center stage but your ears are not in it so you would never hear it unless you mounted your head to the top of the shifter. The goal of the system should be what the listener hears. Nothing else matters IMO.

Equipment is only a small part of the equation. Better equipment has great potential to do better but it doesn't achieve that just by paying for it. I'm not saying that to pass judgement on your system, it probably sounds nice. But regardless of the speaker if you use it improperly you're going to get poor results. This is true in anything but especially in speakers.

saxyman990

Damon, you're getting a little off topic. This thread is supposed to be where to mount the tweeters, not your head. Besides, I don't know about anyone else, but I like my shift ****, and I don't want to drill a hole through it in an effort to mount my head there. There's got to be an easier solution.




Good info though!

-Rob

DamonB

You guys seen that vid of that girl with the shifter where she uh....

rynberg

Yes, thanks for clarifying my post. I meant more like 15-30 deg off-axis, not 90 deg!

A 3dB difference is half the pressure level but is not perceived subjectively as half as loud. It will be a noticeable decrease but at tweeter frequencies, it would require a 10dB decrease in order to sound subjectively half as loud.


You guys need to listen to Damon, he knows what he's talking about. Personally, I'm always surprised when I see very high quality equipment installed in FDs (or cars in general), given the high levels of background noise, poor acoustical environment, and the fact that people are listening to MP3s half the time....