aero port question

[DMV1919 10+ year member]

I'm gonna be building a ported box 1.75-2 (haven't decided yet) cu ft @ 30 hz for a Skar VVX12 given 800 watts @ 2 ohms by a Directed 1500d

The box will be going in the back of a camaro and according to this the best sub/port placement would be upfiring into the glass

I can fire the port towards the glass with a 3" diameter port with no problems, but if I use a 4" port, the port length is too long and i would have to have the port going to a side

Will a 3" port have enough port area or would i be better off with a 4" to the side?

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[Phoenix Risen 10+ year member]

i wouldnt run any less than a 4'' aero on a 12.

i actually use 3''ers on single sa-8 boxes.

 

[RAM_Designs 5,000+ posts]

i wouldnt run any less than a 4'' aero on a 12.
i actually use 3''ers on single sa-8 boxes.

This. If you're wanting to tune low then slot port is going to be much easier to do.

 

[THATpurpleKUSH 5,000+ posts]

You can always run the port externally like in my avatar or even partially external.

 

[Buck 5,000+ posts]

Slot port or elbow ftw.

 

[DMV1919 10+ year member]

thanks guys. i guess i'll be trying to design a slot port box that will fit back there. would about 20 sq inches of port area be good?

 

[THATpurpleKUSH 5,000+ posts]

Thats a little too small, I'd go with around. 25-30 sq in of port area. At 2 cu/ft thats 12.5-15 sq in per cu/ft.

 

[DMV1919 10+ year member]

Alright thanks. Just curious, how does port area affect the sound?

 

[Boomsday 10+ year member]

Slot port or elbow ftw.

Always thought elbows lower efficiency by a bit

 

[THATpurpleKUSH 5,000+ posts]

Too small of a port creates port noise (chuffing). Too large of a port makes the box more peaky and performace below port tuning will fall drastically. (someone correct me if I'm wrong here, pretty sure I got it right though)