Tweeter Phase Separation
11-11-2011, 02:31 AM
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Tweeter Phase Separation Ok, obviously there are a lot of guys here using tweeter pods or windshield pillar mounted tweets. I'm commencing on my own audio build and for design and aesthetic reasons, I was planning on doing tweeter pods as well. But after doing my homework, I'm concerned about this not being an acoustically ideal location for them.
Quoted from CDT Audio
Poor Tweeter placement:
“Never” use the side rear mirror location as your main Tweeter placement! Always mount the main component Tweeter close to the mid woofer location, always!
I think this a bit of an over generalization, but I do take CDT seriously.
First off, let me say I am shooting for all out sound quality with this build. I want a very unobtrusive, non-directional, natural feeling front stage sound presence. In other words, I want the driver or passenger (don't care too much about back seaters) to be able to close their eyes and hear a natural sound stage in front them, fairly centered, without being able to easily say where the speakers are mounted.
That being said, I have read a lot of mixed reviews about separating component drivers. The general consensus seems to be that your main driving tweeters should be mounted as close to the woofer and as on axis with it as possible to ensure everything stays in phase. There are some really high end setups out there with separate 'imaging' tweeters designed just to enhance the front stage presence, but I'm talking about just one pair of components (two mids/woofers and two tweeters).
What it comes down to (as is usually the case with car audio) is that every car is unique and car audio systems must operate within very restricted operating space. So I'm sure with some cars pillar mounted tweets (or dash mounted or upper door mounted) work better than others. With the prevalence of F-Body tweeter pod users out there, I figure you guys may have something to say on this issue specifically. I don't pretend to have 'golden ears', but I'm looking for some serious acoustic reviews here, not just 'it sounds good/bad'. I'm hoping some people out there have seriously listened to a variety of tweeter locations with these concerns in mind. I'd love to test out a bunch of different tweeter locations myself, but I'm laying up my own fiberglass kick panels for the woofers and if the tweeters are going to go there, I need to build them accordingly. The last thing I want is to have to rebuild the kick panels to make room for tweeters because the sound is out of phase, muddled, and distorted. On the flip side, I will be really disappointed if I mount the tweeters in the kick panels, have great high fidelity audio but the stage presence is totally gone because all I can think about it that the sound is coming from the floor. And I really don't want the pain/cost of setting up imaging tweeters all over my dash.
My crossover splits the hi/low signal at 4kHz and after 5kHz, phase is more or less irrelevant to a human listener (I guess our nerves and brains don't work fast enough). At 4-5kHz we are talking about sound waves around 3-4" long so ideally, the distance from listener to any particular driver shouldn't differ by more than that amount. I'm estimating, but I think the difference between the driver's ear and the woofer and the driver's ear and the tweeter pod would be more like 6-8" on the driver side of my Camaro.
Personally, I am using Polk Audio components and the tweeters are silk domed so I don't think they will be terribly harsh regardless of their location. My kick panels are setup to crossfire slightly (left aims a little more toward passenger and right aims a little more toward driver). 10" sub mounted in my own custom fiberglass stealth box, no rear fill speakers for now. My HU even has auto-eq that can also adjust signal phase. While this can help a lot with certain issues, it obviously can't adjust the phase between a single tweeter/woofer pair that are both getting the same signal. So I'm hoping to stir up some serious discussion about the acoustical merits of specific tweeter locations in F-Bodies. Thanks guys.
Quoted from CDT Audio
Poor Tweeter placement:
“Never” use the side rear mirror location as your main Tweeter placement! Always mount the main component Tweeter close to the mid woofer location, always!
I think this a bit of an over generalization, but I do take CDT seriously.
First off, let me say I am shooting for all out sound quality with this build. I want a very unobtrusive, non-directional, natural feeling front stage sound presence. In other words, I want the driver or passenger (don't care too much about back seaters) to be able to close their eyes and hear a natural sound stage in front them, fairly centered, without being able to easily say where the speakers are mounted.
That being said, I have read a lot of mixed reviews about separating component drivers. The general consensus seems to be that your main driving tweeters should be mounted as close to the woofer and as on axis with it as possible to ensure everything stays in phase. There are some really high end setups out there with separate 'imaging' tweeters designed just to enhance the front stage presence, but I'm talking about just one pair of components (two mids/woofers and two tweeters).
What it comes down to (as is usually the case with car audio) is that every car is unique and car audio systems must operate within very restricted operating space. So I'm sure with some cars pillar mounted tweets (or dash mounted or upper door mounted) work better than others. With the prevalence of F-Body tweeter pod users out there, I figure you guys may have something to say on this issue specifically. I don't pretend to have 'golden ears', but I'm looking for some serious acoustic reviews here, not just 'it sounds good/bad'. I'm hoping some people out there have seriously listened to a variety of tweeter locations with these concerns in mind. I'd love to test out a bunch of different tweeter locations myself, but I'm laying up my own fiberglass kick panels for the woofers and if the tweeters are going to go there, I need to build them accordingly. The last thing I want is to have to rebuild the kick panels to make room for tweeters because the sound is out of phase, muddled, and distorted. On the flip side, I will be really disappointed if I mount the tweeters in the kick panels, have great high fidelity audio but the stage presence is totally gone because all I can think about it that the sound is coming from the floor. And I really don't want the pain/cost of setting up imaging tweeters all over my dash.
My crossover splits the hi/low signal at 4kHz and after 5kHz, phase is more or less irrelevant to a human listener (I guess our nerves and brains don't work fast enough). At 4-5kHz we are talking about sound waves around 3-4" long so ideally, the distance from listener to any particular driver shouldn't differ by more than that amount. I'm estimating, but I think the difference between the driver's ear and the woofer and the driver's ear and the tweeter pod would be more like 6-8" on the driver side of my Camaro.
Personally, I am using Polk Audio components and the tweeters are silk domed so I don't think they will be terribly harsh regardless of their location. My kick panels are setup to crossfire slightly (left aims a little more toward passenger and right aims a little more toward driver). 10" sub mounted in my own custom fiberglass stealth box, no rear fill speakers for now. My HU even has auto-eq that can also adjust signal phase. While this can help a lot with certain issues, it obviously can't adjust the phase between a single tweeter/woofer pair that are both getting the same signal. So I'm hoping to stir up some serious discussion about the acoustical merits of specific tweeter locations in F-Bodies. Thanks guys.
