IB vs. oversized sealed enclosure(Theory)

[Trey803 5,000+ posts]

Ok so IB basically like a sealed box just has an infinite (or as close to infinite as you can make it) amount of internal volume. Would making a sealed box larger than recommended make it more like an IB setup. Would an overly large box pose any problems other than reduced power handling and increased risk of bottoming out. I am mainly wanting to know if it will change the linearity of the frequency response in a negative way.

Some people claim IB produce the best sq....if so wouldn't the best sealed enclosure be the biggest one you could fit. Assuming you are using a subwoofer that can be used in an IB setup

When I say sq I am not talking about of the entire system only of the notes produced by the subwoofer so 20-80 ish hz

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[DBDRAGGUY 10+ year member]

Sound Quality would at best be considered listener subjective. I think IB setups sound like azz. In theory a subwoofer is supposed to blend the the bottom end that can't be covered by the midbass drivers. Which in reality is barely audible. If your going to have a subwoofer, put it in a enclosure and attenuate its output for your desired level of so-called sound quality. In short a subwoofer needs an enclosure to really perform,unless your obsessed with "reproduction of the sound stage" add a little boom to your tunes. It sounds good!

 

[Atimm693 10+ year member]

With a big sealed box the top end tends go get a bit sloppy......

 

[Trey803 5,000+ posts]

so in a IB setup.......the top end should also be sloppy right? If so then why do so many claim it to sound so good

 

[Immacomputer 10+ year member]

He probably means that it becomes less boosted by the air spring in the enclosure. It doesn't get "sloppy" but more natural sounding.

That doesn't mean that you should always go as large as possible as some people may not like that. Some people want a system that peaks from about 50-100hz (that "fast" and "tight" sound people describe) and that is easy to get when you use a small sealed enclosure.

The larger you go in a sealed enclosure, the lower the alignment goes (approaches Qts when Fc approaches Fs). The resonant frequency of the system will also drop lower as the enclosure size is increased.

So depending on what you want from your setup, you should design the size around that.

 

[PV Audio 5,000+ posts]

An oversized sealed models about 95% same as the IB with the same baffle dimensions. So yep, your theory is correct. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[Trey803 5,000+ posts]

I think I may try this out! Prolly wont be until Im done with this semester though. I have a good internship lined up for this summer and will be making goooood money and plan on buying a table saw etc.

 

[BrianChia 10+ year member]

Sound Quality would at best be considered listener subjective. I think IB setups sound like azz. In theory a subwoofer is supposed to blend the the bottom end that can't be covered by the midbass drivers. Which in reality is barely audible. If your going to have a subwoofer, put it in a enclosure and attenuate its output for your desired level of so-called sound quality. In short a subwoofer needs an enclosure to really perform,unless your obsessed with "reproduction of the sound stage" add a little boom to your tunes. It sounds good!

Sound quality isn't really that subjective. It is how accurate or how close the reproduced sound is to the original recording. Some aspects of this can be quantified and/or measured.

Something can sound great to you (which is subjective) but that doesn't mean the system necessarily has great sound quality.

 

[Trey803 5,000+ posts]

Sound quality isn't really that subjective. It is how accurate or how close the reproduced sound is to the original recording. Some aspects of this can be quantified and/or measured.
Something can sound great to you (which is subjective) but that doesn't mean the system necessarily has great sound quality.

so does IB produce accurate sq?

 

[PV Audio 5,000+ posts]

so does IB produce accurate sq?

If and ONLY if the driver is suited for it. Otherwise, it'll just bottom out and sound like ****. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[Immacomputer 10+ year member]

so does IB produce accurate sq?

If the driver is very accurate in its design. All infinite baffle does is remove all loading factors from the cone and it puts the suspension of the driver to the test.

 

[Trey803 5,000+ posts]

would the fi q work in IB

 

[Immacomputer 10+ year member]

The 18" and 15" Q would make pretty decent IB drivers but it's really doubtful they would take a full 1000 watts doing so. You could probably reach mechanical power handling around 500-800 watts or maybe even less I bet.

 

[PV Audio 5,000+ posts]

The 18" and 15" Q would make pretty decent IB drivers but it's really doubtful they would take a full 1000 watts doing so. You could probably reach mechanical power handling around 500-800 watts or maybe even less I bet.

Bingo. It seems that drivers with a high Cms/BL ratio do pretty well on IB. If only by logical reasoning, the stronger the suspension and the weaker the motor, it would allow the cone to keep in line easier. Don't quote me on that one as fact though, it's just a personal observation. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[Immacomputer 10+ year member]

Don't forget though that a strong motor can be just as helpful at keeping a coil under control as a stiff suspension can.