ARC Audio Flatlines: Box Specifications

[ModifierMR]

The following question is directed towards Cam2Xrunner....but if anyone else has ideas thats good too.

In january im ordering 2 ARC Audio Flatlines (The one Cam2Xrunner Has). And Im starting to build up my trunk for some amplifiers and subs, I just have a few questions about those subs.

Which is better: Each subwoofer in seperate chambers? Or Both subwoofers sharing the same airspace?

And the flatlines need .9 cu. ft. of air space per subwoofer correct? Is it wise to deviate from that number at all? (eg: 1 cu. ft. instead) Only because it will be easier for me to design the box.

Also what is your suggested break in period/settings for these subwoofers?

thanks

[Tommy]

Always build dual boxes with seperate chambers. supposedly sounds better, and if one sub goes out, you can still use the other one.


building the box 1cu ft will be fine, just throw a bit of poly fill in there, all will be good.

[cam2Xrunner]

The type of box to build (dual or shared) kind of depends on what amp you are going to be using.

A shared airspace enclosure, you will want to use an amp that you can bridge to a mono channel(or a mono amp)

If you are going to be using two seperate channels then you will want to use seperate sealed enclosures.

You can however use a mono amp on a set of subs in their own enclosures. The wiring is a little weird, but it's fine.

If one of the subs blows you will have to rewire it to use just one sub.

So before you design an enclosure, you need to first pic out a sub amp.

Are you sure you need two of these things? One should be plenty.

[ModifierMR]

well, i had 2 MTX's and before that 4 rockfords....i just like it loud, but the reason im going with ARC this time is for the quality.

Im using an Infinity 1210a 2-Channel amp... 1200w @ 2ohms bridged thats what im going to be using

[cam2Xrunner]

I'd go ported with that much power to two of them, and for loudness. It'll still sound good.

Maybe an enclosure like klaymen333 did.

[ModifierMR]

I looked at klaymen333 cardomain profile, i might go for that. Im not good with math and making ports....idk which direction i will go. Would it sound ok sealed? and if i turned the amp down a bit?

[cam2Xrunner]

Sealed you need more power compared to Ported, but you still have enough power for two of them sealed. But yes it will sound excellent sealed. Sealed will typically give you better sound quality while Ported will get louder by typically 3 DB or more.

I like sealed myself. And I like my hearing too, so I use one sealed.

[ModifierMR]

yea, all my boxes i have ever owned have been sealed. I have never had a ported. thanks for the help/advice

[cam2Xrunner]

Originally Posted by BrianOwens

yea, all my boxes i have ever owned have been sealed. I have never had a ported. thanks for the help/advice

You should try both. Were you building your box?

Build a sealed enclosure(s) and build a dual ported enclosure. Try them out, I'd be interested in knowing how it works out for you.

[ModifierMR]

Ok i will try. I can build the Sealed boxes perfect, but ported i have trouble calculating the port and making to exact specifications. But i will do that.

EDIT: When i mean ported i mean the circular ports, not rectangular.

[cam2Xrunner]

Yeah do a slot port. Those are easier and nicer.

I'll see if I can find the cut sheet to build one.

[88 LE]

Port length is calculated based on enclosure volume (total volume minus sub displacement and port displacement), tuning frequency, and size of port.

Port displacement formula for a round port (pipe) is: Pi (3.14) x (radius x radius) x length = cu. in.

cu. in. / 1728 = cu. ft.


Theres 1728 cubic inches in a cubic foot. 12" x 12" x 12" = 1728 cubic inches.


Not sure how to calculate a slot port.

[cam2Xrunner]

Check out this link. It's a bit of a read, but towards the bottom he has a squared port calculator.

http://www.bcae1.com/spboxnew2.htm

Arc reccomends 1.8 cuft @32hZ

[88 LE]

^ To much reading.

I have a JL Audio reference manual. It has port charts.

1.75 cu. ft., 32Hz, 3" port = 8.5" long.

1.875 cu. ft., 32Hz, 3" port = 7.8" long.

So for 1.8 cu. ft. @ 32Hz, I would try a 8" - 8 1/4" long port.



1.75 cu. ft., 32Hz, 4" port = 16" long.

1.875 cu. ft, 32Hz, 4" port = 14.8" long.


Bigger enclosure = shorter port length if tuning frequency is the same.

Bigger diameter port = longer port length if tuning frequency and enclosure volume is the same.

[ModifierMR]

thanks guys, i will build both types and let ya know how it works out.