Thread: ***Airspace help***

Originally Posted by sheepy

Hi there guys. i have just brought two alpine type r 12" subs. I just need a little help with the enclosure. I will be mounting the two subs backwards as well. I have uploaded a copy of a section of the manual with all the enclosure stuff.....please help i don't understand it.

I know that the recommended space is 0.85ft3 but im dont know if i sould be adding the rear mounted displacement to this. If someone could clear this up i would be very grateful. Cheers guys!

I think from what I see use the "reverse mount" added airspace to their recommended airspace.

i think that is the air space you gain when you reverse mount the sub. so subtract .073 from .85 and that'll give you the enclosure size... or don't worry about it since the recommended airspace is .7-1 cu/ft3 sealed

maybe you should look at a program to determine all of this...http://www.linearteam.dk/

to determine what amount of air space you need, you need to figure out how much air space the sub takes up. From there, you need to determine the sub enclosure volume for a normally mounted sub, then subtract the space that the sub takes up.

In all reality, on most subs, the type Rs included, this whole process is neglegable. If you had some beefy sub (think SPL sub) then it would be a different story...

the thing is, while you subtract the amount of air space that the basket takes up...you need to add back the space that's added by the volume of the cone...

so in all reality...for most enclosures, we're talking about very small differences.

Originally Posted by scott_fx

i think that is the air space you gain when you reverse mount the sub. so subtract .073 from .85 and that'll give you the enclosure size... or don't worry about it since the recommended airspace is .7-1 cu/ft3 sealed

So then it will need 0.12ft3 of airspace???? Are u sure!!!

no. 0.85 - 0.073 = 0.777cu/ft3. you missed a 0

Originally Posted by meddler

no. 0.85 - 0.073 = 0.777cu/ft3. you missed a 0

LOL opps....cheers dude!