Burp box...

[kr15 5,000+ posts]

66 is probably a good starting point. It ended up being like 17 per?

 

[shredder1 10+ year member]

66 is probably a good starting point. It ended up being like 17 per?

18.48 in2 area per foot... I'm assuming that's why it gets as loud as it does on the power I'm currently running... I'm kinda liking it... LOL!.. I'm metering it tonight... I hope one is available this week

 

[shredder1 10+ year member]

I'm sorry... it was 68 in2... LOL!

 

[Jeffdachef 5,000+ posts]

There is a point where you lose cone control and dont have enough power to warrant that much port area. And start losing gains and damage your sub.

Where that point is will be based on experimentation

 

[shredder1 10+ year member]

There is a point where you lose cone control and dont have enough power to warrant that much port area. And start losing gains and damage your sub.
Where that point is will be based on experimentation

All right... It all comes back to testing then... I've been told this a lot... I guess I'll see where it is then go from there... as it is, the system has NO issues so far... I'm thankful for THAT... I did a stupid thing once a long time ago... I tried to port my Strokers using the trunk as an enclosure once... man it sounded like God snapped his fingers when those subs bottomed out with about 1500 watts on them... never again... LOL!

 

[shredder1 10+ year member]

Well... it's metered and I'm OK with the results... IDK what was taken where except the highest number was on the floor outlaw...

Attaining a 150 with 2 12's is NO joke... LOL!

 

[kr15 5,000+ posts]

Did you try 52/53 sealed up full tilt?

 

[shredder1 10+ year member]

Did you try 52/53 sealed up full tilt?

Yeah man... I'm slightly smelling coils without the subs getting hot after 2-3 minutes... just like the original Skar recommended box did... only this time I'm able to put a lot more power to it... I'm thinking compression is happening... IDK... I'll try a little more port in the weeks to come... nothing drastic mind you... maybe an increase to 76 in2 and I'll increase net volume accordingly to keep the tune at 46-48 hz... "Frankenbox" will live!.. I'll modify this box... It'll be ugly but functional... LOL!

 

[kr15 5,000+ posts]

Im also a tad louder firing to driver side than back.

 

[shredder1 10+ year member]

Hey I did gain a decent amount... LOL!.. I'm happy... I was the highest number there when I left... LOL!

 

[ChaseinBass]

Not bad at all !

 

[hispls 5,000+ posts]

Yeah man... I'm slightly smelling coils without the subs getting hot after 2-3 minutes... just like the original Skar recommended box did... only this time I'm able to put a lot more power to it... I'm thinking compression is happening... IDK... I'll try a little more port in the weeks to come... nothing drastic mind you... maybe an increase to 76 in2 and I'll increase net volume accordingly to keep the tune at 46-48 hz... "Frankenbox" will live!.. I'll modify this box... It'll be ugly but functional... LOL!

If you're smelling the coils it is because they're getting hot. This is probably because you're throwing 1500w into 1200W subs. What do you think compression is?

That's a respectable score for what you're using though, and gains will be harder and harder to come by the louder you get. You will need access to a meter if you are really chasing numbers. Between gorilla tape and just moving things around you may well be able to gain up to 149 even from where you sit.

 

[shredder1 10+ year member]

Im also a tad louder firing to driver side than back.

Guess what?... I got up today and went out front of the house and the Blazer rear hatch glass was not latched closed... DUH!... I guess I never closed it after I was showing the install and when I metered it it was cracked open an inch or so... still got to 148.5... LOL!

 

[kr15 5,000+ posts]

Nice. It will end up 49+ sealed

 

[shredder1 10+ year member]

I thought about this all day today and I've decided to go all out chasing numbers for a bit... I have taken a lot of great advice... the recurring theme is test and test again... after all the info I've learned I've decided to really start testing a few theories of mine... the suspension on these EVL's is pretty firm and I'm thinking I could increase the port area drastically to make it more efficient at a narrow frequency... I will watch my SSF settings as the last thing I want is to bottom these subs out at high volume... but the box is no longer going to be used musically and I will focus on the 50 hz to 55 hz region... I've already come up with a way to increase port area without changing the box width and still be able to decrease the port area as testing continues quickly and easily...the box width cannot change as it DOES fill the area between the wheel wells almost perfectly... I'll start with a larger area and use inserts to decrease it with time... I can start as high as 100 in2 realistically but have not decided a starting point (it may be less... 86 in2)... If i can model the velocities with up to 3500 watts as the input signal and keep the port velocity at or under 30 m/s... I'll try to use a port area in that neighborhood... Those CAB's at 1/2 ohm can put down some power... I just don't know how much realistically I can expect on my electrical... I am hoping this major port area increase will really let me use the power available at a narrow frequency... the car is dead and sealed pretty good so now I think efficiency is going to be the biggest factor... Here in Phx... I am fortunate to have twice a week meets with a meter usually available so testing is really NOT a problem... Anyone have any tips or thoughts before I do this box surgery?.. I cannot build another without hitting up Lowe's but I do have sufficient scraps just waiting to be put to use... and any input,warnings or thoughts will be welcomed...