Box adjustment

[QuinnyGT 4]

Well chaps I'm not 100% happpy with the SPL of my box, its 16.5cuft before displacement, and tuned onto 30hz, port area is 8.3in^2 per cuft, now recommended space for the subs is 6.5 per driver, and I presume port area should be 10^2inches per cuft, so should I line the entire inside of the box with an extra skin of MDF(flex is another issue except on the front baffle) this will reduce area, and also should I change the port for a larger one on the same tuning?? Any advice greatly appreciated lads

[sefugi 166]

Been doing some planning on a wall myself. Check this site for minimum port sizes and port lengths: http://www.carstereo.com/help/Articles.cfm?id=31

Will be checking back to this thread to see what you are coming up with.

[Duran 387]

Port area is WAYYY small, unless it's a pro audio driver.

What woofers?

[QuinnyGT 4]

Woofers are AA Mayhem 18's they require 6-6.5 cuft each, Will be looking to see exactly what I can do to increase output before I go at tearing the front baffle off

[sefugi 166]

What were your original port dimensions and tuning?

[QuinnyGT 4]

Cant remember exact dimensions, I think its 450mm wide, 150mm high and 500mm long, but final tuning was 30HZ

[sefugi 166]

Cant remember exact dimensions, I think its 450mm wide, 150mm high and 500mm long, but final tuning was 30HZ

That would only be about 100"² and you probly need double that or more.

[QuinnyGT 4]

I thought 10square inches was enough?? Do I defo need double that?? Will the box still play flat??

[sefugi 166]

Port area is WAYYY small

Take a look at this calculator for port area: http://www.carstereo.com/help/Articles.cfm?id=31

What is your actual goal with this setup?

[QuinnyGT 4]

My goal is to be Brutal on Music, BUT 150+DB on music, I have the power supply and equipment so the box is my only let down

[QuinnyGT 4]

Bump anyone??

[sefugi 166]

Have you looked at the site I posted to check your minimum port area?? <-- This will help with your enclosures output! When getting more area for your port you will see that you will start to run out of space with your enclosure because of the port displacement so you will have to find a happy medium between the two. No one can tell you exactly, well I sure can't. BUT you will have to get more output with more port area than you had!

[Duran 387]

Port area is WAYYY small

Take a look at this calculator for port area: http://www.carstereo...icles.cfm?id=31

What is your actual goal with this setup?

I'm well acquainted with Vance Dickason's port area formula, with his woofers, I would use more port area than he has planned.

[BILTD 60]

Joseph

Please send me internal box dimensions. I'll give you the pointers to make it work.

More port area would be better, don't worry to much about musicality I can assure you it will play like a beast. Put up some numbers and I'll do some crunching

[QuinnyGT 4]

Thanks Am, Will be tearing the front baffle off next week, so I will have the dimensions for you chap