Two noob questions about IB

[icor1031]

New(b) guy here!

What I am considering, is this:

Buy four subs, place one in each corner of the ceiling, inside of the (large) attic. They will be 'down firing.'

I do not want to use opposing subs to reduce mechanical vibrating, because I doubt it will be an issue - I do not play at high SPL. I am simply trying to get excellent quality. Multiple subwoofer locations tends to fix nulls.

Last, I would use a 4-channel miniDSP to equalize them.


So, first question:
Are there any problems or improvements that can be made, to what I stated above?



Second question:
I read that the idea is, in an IB system there isn't pressure coming off of the back and hitting the sub again, to color the sound.

So, my question is related to sealed subs: Doesn't having a sealed box mean there is pressure to drive the sub back to it's natural state, and thus it doesn't play a tone as long (time-wise)?
It doesn't have as much, if I recall the term correctly, non-linear distortion.. Correct?


Thanks!

[ThomasW]

Aug 24, 2012 17:31:03 GMT -7 icor1031 said:

So, first question:
Are there any problems or improvements that can be made, to what I stated above?

Use manifolds, ceilings aren't strong and require massive reinforcement to keep the drywall from cracking

Second question:
I read that the idea is, in an IB system there isn't pressure coming off of the back and hitting the sub again, to color the sound.

So, my question is related to sealed subs: Doesn't having a sealed box mean there is pressure to drive the sub back to it's natural state, and thus it doesn't play a tone as long (time-wise)?
It doesn't have as much, if I recall the term correctly, non-linear distortion.. Correct?

The electricity going to a driver is AC [alternating current], that and the driver's suspension are what's causing the cone to move in and out

[icor1031]

Right, but does being in a sealed box help the driver to reset to "0," so to speak - more quickly?

Aug 24, 2012 19:29:00 GMT -7 ThomasW said:

The electricity going to a driver is AC [alternating current], that and the driver's suspension are what's causing the cone to move in and out

[tinnears]

The air in a sealed enclosure acts as a spring.

*boing*
*boing*
*boing*
*boing*

Edit: If you're really worried about mechanical damping of your IB subwoofers then you could add aperiodic membranes. Others will advise against it though.

[icor1031]

I was given more information on the issue, if any one is interested.

techtalk.parts-express.com/showthread.php?233511-Sub-question-open-air-vs-sealed-%28damping-resistance%29&p=1853769#post1853769