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Does anybody know why everybody I see face their subs towards the rear of the car? This seems weird to me. Does it help move more air or something? Will it hurt to turn the box around?
 

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Resident Boost Junkie
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if u turned it around, it would sopund like shit. I did it and my sub sounded like shit ! Then turned it facing tha trunk and sounded much better. I think Bass travels tha opposite way it is fireing. Like when u here a car commin with a system u here tha bass , b4 u see tha car, and then when tha car passes , u really dont here it n e more. So thats why i think everybody points there subs towards tha back, i might b wrong and might b right.
 

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PrOuD To Be HaWaIiAn
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I'm not sure but i think its for the air to travel more, thus making it sound better. If it just bouncesof the seat which is like half a foot away it will sound junk. It sounds better when faced to the back.
 

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OG member
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i think someone said somthing about certain frequencies not coming out clear for the first ten feet or so before it reaches your ear, so that gives it time to hit the back of the trunk and turn around
 

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Alty Go Boom
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I could write like 2 pages on this but in short unless you remove your backseat facing the subs toward the trunk will produce a better louder sound. Only time you face them toward the back seats is if you remove them or have a hatch back.
 

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Frozen Member
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this is oversimplified: if the subs are facing forward, sound waves go back over the box towards the back of your trunk. they then are deflected back towards the box, cancelling out other sound waves. if your sub box it tight against the rear seat so no air can go backwards, you'll be fine. if not, it will be better to face them backwards.

if you turn the box so the subs are facing forwards, notice how if you open the trunk bass performance increases? this is because waves aren't being directed anymore.
 

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Nipponese
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Any soundwave below 80Hz is unidirectional, it has more to do with the proximity to the surrounding surface rather than the direction of the drivers (it's called the "proximity effect").
 

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facing back, yes, the way to go. but, my cousin had his 2 jl 12s facing back, it hit so hard he broke the arms that the lid mounts to. for whatever reason they wouldnt break facing forward so thats how he had to have it.
 

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Resistance is futile
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poisonfist said:
Any soundwave below 80Hz is unidirectional, it has more to do with the proximity to the surrounding surface rather than the direction of the drivers (it's called the "proximity effect").
Exactly. This is demonstrated by the fact that many home audio subs face downward, and can pretty much be placed anywhere in the room ( corners are recommended), yet you don't percieve the sound as coming from any particular direction.
 

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Nissan Pimp *stolen*
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Yes, bass is non directional under 80 Hz, but why is it for some reason that the bass sounds much deeper after bouncing off objects? At least thats what I've found, I have no explanation for it, but as I posted in the other thread, my subs sound much better facing the rear and moved as far back as possible. Then again it may have something to do with having a sealed enclosure. With a ported/vented one I have yet to experience much, I'm now running a single 10" Sony in a ported box (may my 2 MTXs RIP, now I have to use my god forsaken backup sub). I yet yet to experience any good sound of of this sub! :D It almost feels like I'm running on a stock setup! :) Well not really, but nothing like it was bfore, some songs will play nice, but others the bass sounds like crap, damn ported box. (Sealed all the way, and IMO ... Sony, never again) Keep in mind I'm only using it as a backup, cause I had it laying around. I don't think it was ever used, so maybe once the surround breaks in a little, it'll travel a little more and give some better sound.
 

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I could also write quite a bit on it, but here it is VERY simplified.

The further the distance the sub is from you the more pronounced the low bass will be because of the longer wavelength of the lower frequency. when you turn the sub around the distance travelled by the wave to reach your ear is longer and will sound like it is playing lower.
 

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Hazardously WASTED
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also by having them face the rear, there is more air space.

all subs do mostly is move air, if they are facing the rear seat there is less air space for the sound waves to travel through.

if you want a small demo, fold down the back seat and turn the subs facing front. then crack the front drivers window just enough to stick a finger out of. hold your hand up and turn up the bass, you can feel the pulsing movement of the air going in and out of the window.

for better sounding bass, you need a larger air space, thats why the choice for most compitions are suv's, 1: more room for custom boxes and design, and 2: more interior air space to generate a deeper bass and higher db's
 

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Nipponese
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unleaded said:
i am telling you guys, it is all about cancellation of waves
Cancellation only happens with out-of-phase sounds. For that to happen, you need 1/2 the distance of the soundwave to it's proximity wall for it to cancel each other. Another thing is that you need a solid wall that is flat and parallel to the driver, the environment in the trunk prevents this from happening. Rather, in some cases, I would be more worried of the standing waves occuring within the trunk thus amplifying certain frequencies and preventing a nice smooth flat response.
 

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eatmocake said:
i think someone said somthing about certain frequencies not coming out clear for the first ten feet or so before it reaches your ear, so that gives it time to hit the back of the trunk and turn around
Ding Ding Ding...the period of a low end frequency is longer, a lot longer the say 5K.....so it nneds to travel away a bit them the way bounces back and it has the distance to hit you and not over shoot you
 

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Nipponese
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kapsurf said:


Ding Ding Ding...the period of a low end frequency is longer, a lot longer the say 5K.....so it nneds to travel away a bit them the way bounces back and it has the distance to hit you and not over shoot you
You mean wavelength right? Sound travels @ 1,200 kilometers per hour so it travels 33.33 meters per second, a 20Hz soundwave has 20 waves per that 33.33 meters so each wavelength is 1.66 meters (roughly 65 inches). You need that distance from the driver for you to actually hear 20Hz (not many people can really hear down to 20Hz nor up to 18kHz), when you are in a small enclosed space, the reflection of the soundwave start to interfere with each other and start creating harmonics and standing waves. When you play a 20Hz tone in your car, you would be hearing more of the harmonics (40Hz, 80Hz, 160Hz in the order of magnitude are harmonics of 20Hz note) than the actual tone you are trying to reproduce.

Proximity effect is more commonly associated with microphones. You know how your voice sounds a lot deeper when you have the microphone right against your mouth (soundsource)? This happens because of the wavelength of the lower frequencies are farther apart like I explained above. This only happens with omni-directional microphones since the element can pic up sounds from all directions, and the amplifying effect comes from the sound wave picked up from the front as well as the soundwave going around to the back thus amplifying frequencies with larger wavelength than it is from the soundsource. A similar phenomenon happens with the reverse order like speakers putting out low frequencies. The surrounding wall reflects the sound reinforcing the sound generated from the driver, but because this creates a gap of distance from the original sound and the reflected sound, there's a lag of waves and the sound gets a little muddled. You can do an experiment with a speaker of your stereo or a boombox in your room, place the boombox or speaker at the corner of the room against the wall facing it towards the center of the room and play a bass heavy music. Now try increasing the distance from the wall bringing it out more to the center of the room, the sound gains clarity and it sounds cleaner but you don't hear as much bass as before.
 
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