Axiom Home Page Forums General Discussion Home Theater PICS !

Well, it's been a long time coming, but I finally downloaded some photos of my humble little hidaway.. I only hope I post this link correctly.. DOH..
http://s88.photobucket.com/albums/k171/MichaelShoup/The%20Black%20Swan/
Give it a look and let me know what you think.. As with all such projects, it's never done.. (That's my excuse, and I'm sticking to it !)
Enjoy...

That's a VERY slick setup. Have you already told us about the IB sub, if not then.. please...

Are you going to put mains in the garage so you don't waste all that yummy bass ?

Thanks John for those kind words.. The IB's been in operation for about 4 or 5 months now.. It's a great thing to experiance.. Smooth bass from top to 'bottom'.. And yes, I do have an older pair of speakers in the garage, and I do use the back wave.. It really blows people away to here that kind of full sound in ones funky old 2 car garage.. It's a real barn burner on Saturday afternoons !
But the real joy is the theater room itself.. What with the Axioms, the IB, and the big sceen, it's hard to call it quits for the night

Did you serisouly build a sub into your house?

That's awesome.

I think it would be more correct to say that he has a very large subwoofer with a garage door on the back

Mike, what are you using for sub drivers and amplifier ?

Yes, more info and impressions of your IB
I'm seriously considering building one on my soon-to-own home basement.
My basement is about the same size as your HT room: Are two drivers plenty? I’ve read the FAQ on the ‘IB cult’ site, It says that the preferred location for the baffle is the front wall. How’s the front side wall working you? That’s the same location I would have to use for mine. Are you using a BFD (Behringer sp) EQ?
TIA,
Jaime

M80's hung from the ceiling. IB subwoofer.

Extreme!

Looks like a nice couch, too.

I always understood that IB installations preferred some kind of manifold. Is that just a space-saving device? How do you power that thing?

Way cool.

Very extreme indeed! Very cool. I too am curious what you are using to power the IB drivers.

Well, it's kind of embarrassing but the amp I'm using to power the IB is an old Kenwood prologic !? Under powered for the job (120 per channel) but even so, great results.. Smooth bass just rolls out of that puppy.. IB's are to die for when it comes to music, not to mention the earth moving they provide during a good action movie..
As for location, they are very forgiving.. You can mount them behind, above or to the side of the mains with no problem.. It's not recommened, but some have mounted them behind the seating area without complaint..
Yes, I have the BFD, but have not put it on line as yet..
Even without dialing it all in I'm happy..

Hey TT.. Extreme? Well, it was kind of crazy to hang those eighties, but what the heck, someone had to try it
As for the manifold, yes, it's used to fit into locations that a line array wont.. But no real world loss one way of the other.. One plus to the manifold, the speakers physical movements are cancelled out by each other.. The wall that has my two 18's gets to moving quite a bit when I really open it up.. But then, most everything else in the room is dancing some as well, so who knows ?
I'm holding off on the real amp until I build the in-wall shelfs to place all the componets.. It's great to have a garage wall to punch out into with speakers and amps and such ! Gotta luv it..

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

Avalanche 18's, made by Ascendant Audio.. All they appear to be, and more !
It's said it takes more speakers with an IB to give that same pounding that you get with a box.. What they don't say is that pounding is the 1 note the box is tuned to.. Most of the punch in a sound system comes from a well designed and set up set of mains..
It's like a kick drum and bass guitar.. You can't have one without the other.. When a bass and drummer are locked in to each other it can't be beat.. If the bass and kick are not together, you got nothing baby..
Sure, I would love to had a couple more 18's someday, but for now twos more than enough.. I don't even have it powered right, and I'm crazy about the sound ! Jazz never sounded so pure.. I give a lot of credit to the Axioms.. They truly are great speakers..

Simple molly bolts thru the drywall ceiling, small link chain, and screw eyes into the tops of the speakers..
The screw eyes go in slightly to the rear, so when lifted, the speaker hangs forward.. You can then attach a line from the back of the speaker to the rear wall to pull it back to get the angle you want..
Result: No floor to color the sound, and non-parallel walls to the speakers standing wave.. (I sound so high tech! haa)

Hey, that's my old stomping grounds, I lived in HB for 20 years, used to walk my dog to the pier daily

I hear ya man.. Cost is always an issue.. I waited a long time for the deal on the 18's.. And I'm still waiting on the amp.. But with the ib, I can add to it, be it more power or more speakers.. It's modular ! And anyone can build the manifold or baffle board.. It's sooooo easy..
Oh yeah, attach a grill, and it looks like a wall vent.. Check out the IB web site for all the details.. Lots of pics of all the set ups, etc.. http://ibsubwoofers.proboards51.com/index.cgi

I’ve got to quit reading these boards……….I’m now sitting here thinking that I don’t need that bath tub in the spare bedroom’s bath so that I can build one of these things.

Thanks for the info though. Gives me ideas for the next house. Too cool.

So I’m assuming that sub placement is no longer an issue with these IB systems and one could plumb a cabinet duct just about anywhere in the room?

Is there any sort of amp that can run these with remote capabilities? – I didn’t get that far through the web sight.

>>I’ve got to quit reading these boards……….

Me too. I was driving past an RV store yesterday and saw all the trailers and motor homes with bump-outs. Normally I just drive right past, but this time I was thinking "hmm, a retractable manifold, wonder how many woofers you could fit in that ?".

I remember reading somewhere on the 'cult IB' site that it’s recommended that you do the sub crawl using a box sub to find a preferable location. Still, IB location is somewhat less critical than a sub box because of the xover setting is usually much lower than a box. However , I’ve seen a lot on the IB site, that you do need to worry about wave cancellation , which sometimes is related to location & wave reflection.

Some truth to what you say, and some misconceptions.. All subs should be 'placed' and not just plunked down.. The method of putting the box in the sweet-spot and then crawling all over the floor does work.. The IB adds walls and ceilings to the mix.. So, just as Alex suggests using a ladder to check on surround placement, the same applies to the IB..
As for the crossover point being lower, not so.. A sub is a sub.. The type of installation does not change the laws of physics.. Box or IB, 8oHz is 80Hz.. Crossover settings are determinded by the speakers (mains,surrounds,center,subs) abilities, the room acoustics, audio source (movie, music), and your own personal tastes.. 80 hertz is common as most agree that is the point human hearing fails to be able to determine direction.. But again, that is subject to debate, your milage may vary..
Wave cancellation issues:
Sound waves start from a given source (mains,subs,etc) and proceed to bounce all over the freq'n room ! There are lots of excellent sites you can check out, so no need for me to go off on that one..
Ok, I will try one example
A 4 sided body of water (the room).. Rock thrown into water.. (It doesn't have to be rock, jazz or blues will work just the same) But I digress..
Now, here is the part everyone fails to get, the ripples or waves don't move ! They form a peak(s) in one place, and a valley(s) in another.. Peak: Strong signal.. Valley: Weak singal.. You with me ? (I'm not sure right now if I'm with me ?) In other words, as soon as a wave travels from the 1st source, freeze the water ! Get it now ?
But, as we all know, the wave reflects and moves back across the pond (room) creating another 'standing' (frozen) wave.. This 2nd source wave will add too or detract from the 1st wave, boosting the signal, or cancelling it.. Needless to say (but I will) there are an endless amount of reflections going on.. Up down sideways and everything inbetween.. Yeeee Hawwww !!
Remember, this is just 1 rock (sound source).. You try throwing mains, surrounds, a center and a sub or two into that pond, and firing them all up together, you gots yerself a sit-u-aaaaaa-tion..
OK, ok, bottom line, one has to take a few readings around the room, (ratshack meeter/pc/free software) find what's going on with the peaks/nodes, and then fix it as best you can.. Move speakers, move furniture, acoustic panels, etc..
One of the best things you can do to manage a sub is to purchace a Parametric Equalizer, or BFD as it's more affectionately know.. More on that here: http://www.behringer.com/DSP1124P/index.cfm?lang=ENG
Well now, that was easy Time for my nap..
Ta..

Mikey, Mikey, wake up. One question... how much does the sound/frequency/sensation of the LFE change in your room if the garage door is open vs. closed. In other words, the port is open vs. closed? Just a thought.

Whoa, man those black 80s hanging from the ceiling/wall almost look demonic ... but slick as heck. How did you manage to ever get them up there and how do they sound compared to being on the floor? The IB is also slick setup and I'm wondering if you get any more sound carry over into the garage area?

Thanks for the pics and the sound wave explanation, I cracked a smile reading it.

Sorry man.. Adult beverages are not allowed at work as you would expect, but no limit on the amount of fresh Columbian coffee you can drink !?! I was flying when I typed all that out !
Now that you mention it, I do recall a drop in sound pressure when me wife came home the other night

I'm crazy in love with the sound Rick.. It's pure, no added bass boost from the floor.. As much as I love a full sound, top to bottom, I'm a 'mid freq' freak at heart, and my 80's fill the bill.. Bass may make things fall off the shelf, but it's the mid's that really nail ya down !
Stevie Ray knew that, running heavy gauge strings to get the sound he was so famous for.. No damn slinky's on that mans axe !!
And yes, I have a 2nd set of speakers in the garage, and I use the back side of the subs when I'm working there..
It's just too much fun for someone my age to have