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Outrageous set-up man. I have been really curious as to just how these IB subs sound. Who makes those impressive drivers that you are using? I'm afraid that whole WAF thing just wouldn't work for me though. (heavy sigh)

>>I'm afraid that whole WAF thing just wouldn't work for me though.

Just hang the grill cloth in the listening room, then tell your wife you decided to install the subwoofer in the garage so the HT room would look nice for her

Am I the only one who doesn’t know what the hell “IB” stands for???

Love the flying speakers. How did you end up hanging them?

IB = Infinite Baffle. It refers to speakers mounted in a way that leaves their cones unrestricted by a typical enclosure and basically operating in "free air." Basically, it's a boxless speaker. The advantage of infinite baffle, especially when you're talking about subwoofers, is flat response. The disadvantage is that you trade off power and depth for that flatness. To regain that power and depth, you need to use more drivers. Here's how one guy did it.

This should give you all the info you need about IBs and the people who build them. http://ibsubwoofers.proboards51.com/index.cgi

One of the challenges when designing a speaker is what to do with the "back wave", ie the signal off the back of the speaker. If you don't do anything, then the back wave cancels out the front wave at lower frequencies -- that's why a speaker sitting out on the table always sounds tinny unless you put it in an enclosure.

There are a variety of different things you can do with the back wave. The simplest is a sealed and damped box ("acoustic suspension") which absorbs the back wave and provides extra "spring" for the woofer cone, but the downside is that the extra spring raises the resonant frequency of the speaker so you can lose some deep bass.

Bass Reflex speakers use a tuned, resonant enclosure with a port so that at a specific frequency the back wave coming out of the port has been inverted and is now in phase with the signal coming off the front of the speaker. This gives you a nice bass boost right at the point where the speaker would otherwise be rolling off, and the resonating air inside the enclosure helps to control cone movement at very low frequencies but doesn't affect the resonant frequency as much as a sealed box.

A transmission line accomplishes pretty much the same thing but actually uses a long folded path so that the time delay from speaker to port is enough to bring the back wave in phase with the front wave.

The idea of Infinite Baffle comes from the use of a baffle board (a board with the speaker mounted in it) which provided better LF response by keeping the front and back waves apart until much lower frequencies -- the bigger the board, the lower frequencies you can get before the front and back wave combines. An Infinite Baffle uses the wall and room behind to provide the same effect as an infinitely large baffle board.

You could also call it an infinitely large sealed enclosure but AFAIK most IB fans think sealed subs are wussy

Geez, it really *is* a cult...



Funny how they don't want questions about IB car audio systems. That would seem like a natural, at least if you had a nice quiet car

Wow, those are 18"s, I though they were 15"s from the picture side by side to the M60 …er, wait a minute, that‘s a M80 … never mind

Thanks, for the info MIKEY. I've already done the numbers for a 4-15” drivers rig. It’ll cost me about the same of a HSU VTF3mkII. However, I'm giving more weight to the higher WAF the IB might have, and the excuse to go and buy some power tools.
Great HT room you have there...

IB+car=rattlerattlerattlerattlerattle...

Strange how my neighbors have yet to figure that one out.

I live near the Huntington Beach pier, and we got quite a few kids crusin by with their too cool '1 note' sound systems