Subwoofers pointing forwards or backwards?

phonixx · Post by **phonixx** » Sun May 31, 2009 10:55 am

Hi guys!

Have you tested pointing the subwoofers both ways in the same car? Like take the same box and let it play first against the backlights of your car and then turn it and let the same box play in the direction through the backseat and into the cabin? If so what direction did play best? SQ\SPL?

My first car was an Audi and it had the fueltank covering the hole backseat in the trunck so there i had 2*12" playing backward against the lights\plate and it worked very well but now in my Volvo the backside of the backseat is cind of open and there is a skihole to so here the woofers is playing i forward direction and that is working vell to. Have any of you any opinion of what direction working best?

Thanx
Bjornar

Pedi · Post by **Pedi** » Sun May 31, 2009 11:04 am

Bjørnar, I still vote for the backwards direction..

I think we need to discuss this over a beer and a BBQ, like we discussed..

(PS... I might have 4 weeks off now, going home from work tomorrow...)

dBincognito · Post by **dBincognito** » Sun May 31, 2009 11:05 am

My friends would slap me if my subwoofer faced the cabin

phonixx · Post by **phonixx** » Sun May 31, 2009 11:07 am

I know Pedi, and you did not even had a fueltank to argue with in your bimer

maybe i vote for the backward direction in my volvo to, i just havent tried it yet

Pedi · Post by **Pedi** » Sun May 31, 2009 11:09 am

As far as I remember, the closer to the backlights the better. Your box is really far away from the lights, am I not right?

phonixx · Post by **phonixx** » Sun May 31, 2009 11:14 am

Yes that was my experience to so i sat up a 22mm plate of wood between the woofres and the backlights. That resulted in more punch and longer life for my backlights

But now the box is far away from the lights yes so that may be a problem but i may try and see what happens and then try to set up a 22mm plate in front of the subs.

Lets take this over a BBQ yes

phonixx · Post by **phonixx** » Sun May 31, 2009 11:16 am

dBincognito wrote:My friends would slap me if my subwoofer faced the cabin

Hehe you are always letting your subwoofers playing backwards right? Is that to get most SPL or why do you do it?

Thanx
Bjornar

dBincognito · Post by **dBincognito** » Sun May 31, 2009 11:18 am

phonixx wrote:
dBincognito wrote:My friends would slap me if my subwoofer faced the cabin
Hehe you are always letting your subwoofers playing backwards right? Is that to get most SPL or why do you do it?

Thanx
Bjornar

Yes, the sub will be much louder.....if you had a van the difference is enormous

Pedi · Post by **Pedi** » Sun May 31, 2009 11:19 am

phonixx wrote:
Lets take this over a BBQ yes

You got a deal there...

Åse is talking about inviting you so, so she will be thrilled... Bring the dog, so Åse will be buzy with that one - and we can talk PG..

Have you tried to mount a 22mm plate next to the box where it is now? maybe that would help?

Pedi · Post by **Pedi** » Sun May 31, 2009 11:20 am

dBincognito wrote:

Yes, the sub will be much louder.....if you had a van the difference is enormous

What about the Steve M. solution, instead of a backwards solution in a van?

dBincognito · Post by **dBincognito** » Sun May 31, 2009 11:21 am

Pedi wrote:
dBincognito wrote:

Yes, the sub will be much louder.....if you had a van the difference is enormous
What about the Steve M. solution, instead of a backwards solution in a van?

Not familiar with that

phonixx · Post by **phonixx** » Sun May 31, 2009 11:22 am

dBincognito wrote:
phonixx wrote:
dBincognito wrote:My friends would slap me if my subwoofer faced the cabin
Hehe you are always letting your subwoofers playing backwards right? Is that to get most SPL or why do you do it?

Thanx
Bjornar

Yes, the sub will be much louder.....if you had a van the difference is enormous

Thanx, must the Subbox be placed tight up against the backwall in the car or will it play louder even when there is a "long way" before the sound hits the backwall?

Bjornar

phonixx · Post by **phonixx** » Sun May 31, 2009 11:24 am

Pedi wrote:
phonixx wrote:
Lets take this over a BBQ yes
You got a deal there...

Åse is talking about inviting you so, so she will be thrilled... Bring the dog, so Åse will be buzy with that one - and we can talk PG..

Have you tried to mount a 22mm plate next to the box where it is now? maybe that would help?

There is no space for it now, the front of the subs is just a few centimeters from the backseat, they are playing against the cabin you know, i bring the dog

Pedi · Post by **Pedi** » Sun May 31, 2009 11:24 am

dBincognito wrote: Not familiar with that

Steve Meade, or something...

Got a few 18"s in his car, with 2 outstanding RF amps..

Check it out, and tell us your opinion compared to the backward solution

dBincognito · Post by **dBincognito** » Sun May 31, 2009 11:25 am

phonixx wrote:
dBincognito wrote:
phonixx wrote: Hehe you are always letting your subwoofers playing backwards right? Is that to get most SPL or why do you do it?

Thanx
Bjornar

Yes, the sub will be much louder.....if you had a van the difference is enormous
Thanx, must the Subbox be placed tight up against the backwall in the car or will it play louder even when there is a "long way" before the sound hits the backwall?

Bjornar

You have to experiment with placing a bit......every car tends to respond differently.

Pedi · Post by **Pedi** » Sun May 31, 2009 11:25 am

phonixx wrote:
There is no space for it now, the front of the subs is just a few centimeters from the backseat, they are playing against the cabin you know, i bring the dog

Yeah, I know - but if you turn the box backwards where it is now... Tried that? And for fun - with a 22mm plate afterwards?

phonixx · Post by **phonixx** » Sun May 31, 2009 11:30 am

dBincognito wrote: You have to experiment with placing a bit......every car tends to respond differently.

Thanx i will do that, i have always had the feeling that the backward direction was the best\loudest since i had it in my good old Audi 80 back in the early 90`s

Bjornar

phonixx · Post by **phonixx** » Sun May 31, 2009 11:32 am

Pedi wrote:
phonixx wrote:
There is no space for it now, the front of the subs is just a few centimeters from the backseat, they are playing against the cabin you know, i bring the dog
Yeah, I know - but if you turn the box backwards where it is now... Tried that? And for fun - with a 22mm plate afterwards?

Yes i really must try that, no doubt about it, i try with a 22mm in different places to.

Pedi · Post by **Pedi** » Sun May 31, 2009 11:48 am

Have you ever tested with a dB-meter?

I have one....

brenzbmr@sb · Post by **brenzbmr@sb** » Sun May 31, 2009 1:26 pm

the reason it "sounds better " facing back of trunk is because of phase
shift due to reflections in trunk.

having it face forward and not sealing the front of woofer from rear of box will cause unwanted phase shift due to reflections and there fore u will hear the differnce.

by facing them to the lights the phase of the reflections are alot closer and less damaging..

we used to use a load board so that it would take the stress off of the trunk and lights...

my prefernce will always be facing forward and sealed off (or walled off)

u can hear more detail in the bass that way.

if u sat in my lexus u would hear some serious low end and i have it all facing forward and very little phase shift in the low freq.

but its all up to the person and there goals.

Post by **stipud** » Sun May 31, 2009 3:33 pm

You should only point the subs in if you completely seal them into the cabin. Otherwise, aiming to the rear will minimize cancellation, and you will almost always get the most output.

phonixx · Post by **phonixx** » Sun May 31, 2009 4:27 pm

Thanx guys for a really good thread about this topic, me and Pedi has been talking about this now and then for the last 10 years as we both did by no doubt the highest SPL with the Subwoofers pointing backwards.

I have mine pointing forward right now but i have not sealed the backside like i should.

Thanx
Bjornar

Stryker · Post by **Stryker** » Sun May 31, 2009 5:10 pm

stipud wrote:You should only point the subs in if you completely seal them into the cabin. Otherwise, aiming to the rear will minimize cancellation, and you will almost always get the most output.

I have done this and had my system like this for awhile. I completely sealed the face of the sub box from the trunk. there is absolutely no way there is any cancellation. I also use the back of the seat as a pseudo corner load.

I've used expanding foam to do the sealing from the trunk to the front, then the sound deadener mat on top of this. you can look at my install log if you want to see it. think of your sub box in a box,(your cars cabin) the smaller you make the box outside of your sub box the better....more pressure. there was a long article about this awhile ago in CA&E. this being said, when I had a Chev astro van I pointed to the rear and reinforced the back doors and it hit very hard. If you're going to point them forward in a trunk type car prepare to do some expanding foam work and seal it off, otherwise point them to the back. I would never point them backwards again after doing it both ways with the same car. it wasn't night and day diff., but it was certainly noticeable to me.

Post by **fuzzysnuggleduck** » Mon Jun 01, 2009 8:54 am

Avoiding/minimizing standing waves is key.

http://en.wikipedia.org/wiki/Standing_wave

For most installations, this means pointing the subs backwards. Of course, the sealing techniques mentioned here have the same effect of reducing standing waves.

bogart · Post by **bogart** » Mon Jun 01, 2009 9:35 am

I was forced to run my solo x 12s facing into the back seat sealed as they kept popping the truck open...I was quite displeased with how they ran like this. One the interior noise was ten times worse...two they sounded dampened and dull in the upper bass frequencies...did well around 30hz but the backseat and deck lid were all over the car and it eventually broke the seat bracket and the rear trim brackets. it they fire forward they need to be in the far back of the trunk and sealed....

the next question is what are your goals for staging....what kind of system are you really trying to build and what are your goals

he is 100% correct that it is all about killing standing waves in the car...unless you are going for pure spl...then there is not way you can avoid it...the system is designed to run above frequencies where cancellation occurs...the one note wonder where your sub is run from 55 to 65 hz and the peak centered at 60.

I've done this...and it was fun...but I got really tired of the bass meckanics, paul wall and dj majic mike after a few months...and it destroyed the car...ripped sheet metal actually....and my trunk lid hasn't worked right since...but it was fun fun fun and my neighbors now hate hate hate me and thats ok too....pricks