canadian123

Hey Guys

I need some help with box design it has been awhile since I competed in SPL cometition and I'm quite rusty but I'm very excited to be back in it.

This is what I have so far for my set up

Audiobahn immortal 15'' quad 2ohm coils ( a co-worker had it sitting in his basement got it for free and its brand new )
2- EXILE 2400.1 straped at 2 ohms for 4800wrms
0ga from front to rear 800cca battery under the hood
The big 3 in 0ga
1000cca battery in the trunk
0ga to the amps


now this is in a 91 corolla the box is in the trunk facing into the cabin it is aprox 5.9 cuft the measurements are as follows.

OD 33x16x24 port will be 13x14.75 so 191sqin looking to tune it to 65hz my length is comming up as 10'' does this sound right.


any help with the box would be awsome open to any advice.


Thanks in advance

Lessy

i think your port might be too big and your tuning too high

canadian123

I know box building programs are only used as a building aid and in car tuning is the way to go but I'm seeing a 15db spike at 70hz when tuned to 65hz where as I only see a 11.5db spike at 57hz when tuned to 50hz. Wouldnt it be smarter to use the tuning fq that gives the highest spike under 100hz or 80hz depending on the legue your competing in. This is where I need advice cause I just have a lack experience with SPL over the last 5yrs so I need to learn everything again.

I can adjust the size of the port from 14.5x14.75 down to 14.5x0 if I have to I know you want the same sqin of port as your sub so that would be 135sqin so 14.5x9.5 so i'm getting 16.35'' for the length.

Thanks for the help

worldind

iTrader: (17)

I tried a box modelled after similar winisd suggestions and it peaked way high, like 65hz or so... the next box I tried was the same volume but tuned into the 40's. It peaked at 51hz, and I gained (contrary to what the program said should happen). The moral of the story is don't do drugs. Also don't trust the program.

canadian123

cool so I will just start testing starting around 45hz and try a few different ports till I find the ticket.

what do you think about the sqin area of the port should I keep it around the 135 mark or should I use the whole 213sqin I have available.

Lessy

smaller, around 113 should be good enough

canadian123

Thanks Less

so something got screwed up and I only got one amp it is 1ohm stable on a quad 2ohm sub I have hook up for .5ohm or 2ohm so either I can over run the amp or run it at half power.

can you run 2 coils of the 4 to make a 1ohm load or is this a no no?

Lessy

1 amp should take 0.5 ohm for burps

canadian123

thats What I figured but I dont really want to smoke a $1k amp with one burp. I got to call Exile tomorrow and find out what happened to the second amp.

worldind

iTrader: (17)

From what I've heard from the BC crew, .5 ohm isn't a big issue with those exiles...