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why am I bottoming out?


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Today I built a box for my 12" TC9 proto. The sub can supposedly it can handle up to 1500rms. It's dual 2 ohm (each coil is sitting at a constant 1.7ohm). The box is 2.2 cubes tuned to 34hz with 12 sq in of port per cube (14.5h x 18w x 24d). I'm only running 600rms to it via JBL monoblock @1ohm. It has no subsonic filter (guessing it's built in), lowpass is around 80, and gains were set with my DD-1.

I built the box long, instead of wide, with sub and port on the front of the box. This is roughly what it looks like (and enjoy my artwork).

tc9box.png

When I play really loud, my sub starts bottoming out on some lower frequencies. I heard the coil bounce off the backplate a couple times, but got to the volume knob before it was too late. Also, some lower notes seem to have that "unloading" sound. Is this all happening because of there being too much airspace behind the cone of my woofer?

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2005 Subaru Impreza

My build log.

Head unit- Kenwood Excelon KDC-X695

Front doors- Rockford Fosgate 6.5" Prime components

Rear doors- Rockford Fosgate 4" Punch coaxials

Sub amp- Audiopipe AP18001d

Subs- Two American Bass TNT 10"s

Box- 2.6 cubes @ 34hz, 36in of port

Big 3 & run of Raptor 1/0 to rear powercell

TEAM 808 UPSTATE NY.

ab1.png

Can it be heard 2 blocks away, thats how i rate systems.

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Could be unloading to the port, depends on port placement, or not enough pressure inside of the box. Maybe to big of a box, try shinking the box some internal. The soft parts may not be suited for that much airspace, normally tc subwoofers like smaller boxes if i remember correctly.

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Kenwood H/U

1/0 wire,

136 amp alt 200 ah batteries 12.7 daily

2 Apsm 1500 @ 2 ohm strapped on zv3 d1 with ns softparts

Mb quart 125.4 wired to 4 aura 6's

3.6 cube box tuned to 36 plays down to 23hz

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2.2 for a 12 is pretty big. Shrink down to 1.9-2.0 and see what happens.

i'm not shunning your advice man, but everyone on here says "underpowering sub=bigger box" haha. i used to love building boxes, but now it just seems like such a chore, i dont wanna do it again.

SUBSCRIBE AT YOUTUBE! 18abVFL < CLICK!!

2005 Subaru Impreza

My build log.

Head unit- Kenwood Excelon KDC-X695

Front doors- Rockford Fosgate 6.5" Prime components

Rear doors- Rockford Fosgate 4" Punch coaxials

Sub amp- Audiopipe AP18001d

Subs- Two American Bass TNT 10"s

Box- 2.6 cubes @ 34hz, 36in of port

Big 3 & run of Raptor 1/0 to rear powercell

TEAM 808 UPSTATE NY.

ab1.png

Can it be heard 2 blocks away, thats how i rate systems.

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maybe the coil can handle 1500rms thermally, but the suspension isnt stiff enough for 1500rms.

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Best Score to Date : 160.5 dB Outlaw (47Hz)[4 XM 15's & 2 Taramps Bass 12k's]

BL :  http://www.stevemeadedesigns.com/board/topic/147800-chevyboy95s-4-15s-7krms-wall-1533-db-on-half-power/
YouTube: http://www.youtube.com/hitemwiththeflex/

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maybe your box wasnt built/ tuned/designed like you thought it was?

Edited by Bump4life

Buyer/Seller Feedback Thread: http://www.stevemead...5015-bump4life/
MB C220 153 Trunk Car Build Log: http://www.stevemead...d/#entry1840136
MB C280 Ipad Dash SQ Build Log: http://www.stevemeadedesigns.com/board/topic/194484-bump4lifes-new-benz-tony-c-relay-kit-pictures-ce-electric-audison-front-stage-installed/
My SPL Log: http://www.stevemead...__fromsearch__1

BMW M340 xDrive

Stock, for now. Corner Load 10" maybe soon. But does 10s in the 1/4...
Best Scores out of a trunk
153.0 sealed legal full tilt clamped 5524 @ 42 hz
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maybe your box wasnt built/ tuned/designed like you thought it was?

boxx.png

SUBSCRIBE AT YOUTUBE! 18abVFL < CLICK!!

2005 Subaru Impreza

My build log.

Head unit- Kenwood Excelon KDC-X695

Front doors- Rockford Fosgate 6.5" Prime components

Rear doors- Rockford Fosgate 4" Punch coaxials

Sub amp- Audiopipe AP18001d

Subs- Two American Bass TNT 10"s

Box- 2.6 cubes @ 34hz, 36in of port

Big 3 & run of Raptor 1/0 to rear powercell

TEAM 808 UPSTATE NY.

ab1.png

Can it be heard 2 blocks away, thats how i rate systems.

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Share on other sites

maybe the coil can handle 1500rms thermally, but the suspension isnt stiff enough for 1500rms.

im only giving it 600rms...

SUBSCRIBE AT YOUTUBE! 18abVFL < CLICK!!

2005 Subaru Impreza

My build log.

Head unit- Kenwood Excelon KDC-X695

Front doors- Rockford Fosgate 6.5" Prime components

Rear doors- Rockford Fosgate 4" Punch coaxials

Sub amp- Audiopipe AP18001d

Subs- Two American Bass TNT 10"s

Box- 2.6 cubes @ 34hz, 36in of port

Big 3 & run of Raptor 1/0 to rear powercell

TEAM 808 UPSTATE NY.

ab1.png

Can it be heard 2 blocks away, thats how i rate systems.

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Share on other sites

idk if your amp has a sub sonic filter built in?

Buyer/Seller Feedback Thread: http://www.stevemead...5015-bump4life/
MB C220 153 Trunk Car Build Log: http://www.stevemead...d/#entry1840136
MB C280 Ipad Dash SQ Build Log: http://www.stevemeadedesigns.com/board/topic/194484-bump4lifes-new-benz-tony-c-relay-kit-pictures-ce-electric-audison-front-stage-installed/
My SPL Log: http://www.stevemead...__fromsearch__1

BMW M340 xDrive

Stock, for now. Corner Load 10" maybe soon. But does 10s in the 1/4...
Best Scores out of a trunk
153.0 sealed legal full tilt clamped 5524 @ 42 hz
154+ windows down, 155+ kick

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idk if your amp has a sub sonic filter built in?

lol me eiths brah

SUBSCRIBE AT YOUTUBE! 18abVFL < CLICK!!

2005 Subaru Impreza

My build log.

Head unit- Kenwood Excelon KDC-X695

Front doors- Rockford Fosgate 6.5" Prime components

Rear doors- Rockford Fosgate 4" Punch coaxials

Sub amp- Audiopipe AP18001d

Subs- Two American Bass TNT 10"s

Box- 2.6 cubes @ 34hz, 36in of port

Big 3 & run of Raptor 1/0 to rear powercell

TEAM 808 UPSTATE NY.

ab1.png

Can it be heard 2 blocks away, thats how i rate systems.

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