DIY port to the trunk behind rear arm-rest?

Joe Bimmer · 06-26-2006, 12:08 AM

I'm thinking of installing subs in my E90, but the sound will be muted without a port into the cabin. I tried searching until my head was about to explode. Does anyone have any pics of a port behind the fold-down rear arm-rest from the back seat into the trunk? I noticed there's a plastic piece behind the arm rest...but unsure what's between that and the trunk...any tips would be awesome!

Thanks!

XI JR IX · 06-30-2006, 08:24 AM

Quote:

Originally Posted by Joe Bimmer

I'm thinking of installing subs in my E90, but the sound will be muted without a port into the cabin. I tried searching until my head was about to explode. Does anyone have any pics of a port behind the fold-down rear arm-rest from the back seat into the trunk? I noticed there's a plastic piece behind the arm rest...but unsure what's between that and the trunk...any tips would be awesome!

Thanks!

Won't be muted at all.. I have 2 12"s in a normal sealed box facing towards my trunk and it pounds hard.. only rattle came from the licence plate cover which was then removed..

ksfrogman · 06-30-2006, 08:56 AM

If you don't have fold down rear seats, and you really want to "port" the trunk, you might consider doing what I did to my ex-wife's Impreza.

I took off the rear deck panel interior, so I could see the bare metal, and took an air compressor powered cut-off saw to it. I cut about three or four rectangular openings that followed the countour of the pre-molded metal deck, and reinstalled the cloth lined deck panel. The subwoofer vibrations no longer rattled the trunk, nor sounded muted (because they did originally).

Btw, the subwoofer was the vented enclosed type.

puck724 · 06-30-2006, 01:23 PM

if you ahve the cold weather package that plastic thing in the armrest comes out. all it is is the storage for the ski bag.

ScotyH · 06-30-2006, 05:30 PM

If you leave the rear armrest down and take that bag holder thingy out, you'll get 4db's more bass output. That's a bit more volume than if you were to double your subwoofer amp power. I have tested it with a variety of test tones and thats about the average gain.

06-26-2006, 12:08 AM	#1
Joe Bimmer Lieutenant 14 Rep 548 Posts Drives: Alpine White 2015 X5 x35i Join Date: May 2006 Location: Austin, TX iTrader: (0) Garage List 2006 325i [0.00]	DIY port to the trunk behind rear arm-rest? I'm thinking of installing subs in my E90, but the sound will be muted without a port into the cabin. I tried searching until my head was about to explode. Does anyone have any pics of a port behind the fold-down rear arm-rest from the back seat into the trunk? I noticed there's a plastic piece behind the arm rest...but unsure what's between that and the trunk...any tips would be awesome! Thanks!
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06-30-2006, 08:56 AM	#3
ksfrogman Major General 784 Rep 6,750 Posts Drives: E90 330i 6MT Join Date: Nov 2005 Location: Torrance, CA iTrader: (12) Garage List 2006 330i [0.00] 2006 330i [0.00]	If you don't have fold down rear seats, and you really want to "port" the trunk, you might consider doing what I did to my ex-wife's Impreza. I took off the rear deck panel interior, so I could see the bare metal, and took an air compressor powered cut-off saw to it. I cut about three or four rectangular openings that followed the countour of the pre-molded metal deck, and reinstalled the cloth lined deck panel. The subwoofer vibrations no longer rattled the trunk, nor sounded muted (because they did originally). Btw, the subwoofer was the vented enclosed type. __________________
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06-30-2006, 01:23 PM	#4
puck724 COLTS 4 LIFE!!! 115 Rep 1,746 Posts Drives: 2006 330i Join Date: Aug 2005 Location: california iTrader: (1) Garage List 2006 330i [5.00]	if you ahve the cold weather package that plastic thing in the armrest comes out. all it is is the storage for the ski bag. __________________ 2006 330i --sapphire black--black leather --alumminum trim --premium package --cold weather package --park distace control --automatic transmission --navigation with iDrive
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06-30-2006, 05:30 PM	#5
ScotyH Bimmer me up 22 Rep 340 Posts Drives: 08 M3, 2010 GTR Join Date: Sep 2005 Location: Edmonton,AB iTrader: (0)	If you leave the rear armrest down and take that bag holder thingy out, you'll get 4db's more bass output. That's a bit more volume than if you were to double your subwoofer amp power. I have tested it with a variety of test tones and thats about the average gain.
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