8ft long SUB w/ 4-18" Obsidian/SI drivers

DonH50

Member Sponsor & WBF Technical Expert
Jun 22, 2010
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Thanks, just wondered. There are so many parameters to play with in speaker design (and I am not a speaker designer, just played at it now and then) I was just curious as to what drove the choice (should have known driver parameters).

@NorthStar: A lot of recordings have some content below 20 Hz, though it's not much in most I agree. I have found sub-20 Hz content more often than I expected in various jazz and classical CDs, mainly from the drums (natch).

IME few people realize how low 20 Hz really is and how loud it has to be to really feel it. Most "bass freaks" are really listening to the 40 - 80 band. Basspig a notable exception, of course. :)
 

16hz lover

Well-Known Member
Aug 2, 2013
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Thanks for the replies. I might have forgot to put in the first post that this was designed for exactly like several of you have mentioned....90% MUSIC, concentrating on 20-80hz.
I'll have to admit that I'm not a TV or movie fan( my wife is the tv holic) I just hate watching violence of any kind, so that eliminates about 90% of all the movies out there.

For really low stuff I have a IB box mounted up in the attic that had 4 of the 18" SI woofers in it, but removed them for another project. Now I'm converting it to accept the new Stereo Integrity 24" monster driver they just came out with. I'll put another amplifier on it and likely run it from 40hz on down, Think that will do?
 

16hz lover

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Aug 2, 2013
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"I built it in two pieces in case I needed to break it down in the future to move it."

SMART, Intelligent, common sense being.

Question: are you an Earthling or a visitor from an advanced culture?

After removing the four drivers, the top can be unscrewed from underneath, then the 4 big bolts that hold the two cabinets together can be taken out and the two cabinets can then be transported rather easily. I would like to own a house in the future with a basement and a dedicated room for audio/video.

There is a saying," Contentment is destroyed by comparison" Once you hear a full speaker system that will play the bottom octaves with authority, you are not satisfies with mere 1 driver subs that fail to impart a pressure wave that permeates your body and makes you become one with the music. being a former drummer and trumpeter for many years playing in 18 piece Big Bands at 100db plus levels, you become used to "feeling the music". Most audiophiles don't have any desire at all for this kind of system, which I found out at last years CES show. 200K dollar systems that fail to reproduce percussion with realism, room after room of ultra expensive systems that went to 40hz at very moderate levels as well. One mfg'r had a pair of 30K speakers that had a great bottom end until I asked to turn it up to the level of having the musicians in the room, to which the woofers quickly bottomed out on the first kick drum hit, and he said that he had sold 50 pairs of them so far. Playing in Big Bands let you experience what musical/physical energy can be had, just like playing in the middle of an orchestra and having a large orchestral drum being walloped right behind you. A complete different experience from being out in the 14th row of the Concert Hall. Hope this helps you understand the goal I am after in my setup, which is the perfect blend of SQ and SPL

My wife sometimes does question my sanity. , ...this is the Insane Asylum of the Universe.
 

NorthStar

Member
Feb 8, 2011
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435
Vancouver Island, B.C. Canada
Thanks for the replies. I might have forgot to put in the first post that this was designed for exactly like several of you have mentioned....90% MUSIC, concentrating on 20-80hz.
I'll have to admit that I'm not a TV or movie fan( my wife is the tv holic) I just hate watching violence of any kind, so that eliminates about 90% of all the movies out there.

For really low stuff I have a IB box mounted up in the attic that had 4 of the 18" SI woofers in it, but removed them for another project. Now I'm converting it to accept the new Stereo Integrity 24" monster driver they just came out with.
I'll put another amplifier on it and likely run it from 40hz on down, Think that will do?

Oh yeah.
 

16hz lover

Well-Known Member
Aug 2, 2013
234
15
70
I am a Subaholic, just can't get enough of it. It ranks right up there with sex...almost.:D
 

16hz lover

Well-Known Member
Aug 2, 2013
234
15
70
Still a little ways from getting some measurements on f and spl in the room due to having an amp crap out on me, so I'm working on getting a replacement for it soon. I want to see what kind of spl I can get at 30 and 20hz frequencies in my very large room.
 

JonFo

Well-Known Member
Jun 11, 2010
322
1
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Big Canoe, GA
www.jonathanfoulkes.com
...
For really low stuff I have a IB box mounted up in the attic that had 4 of the 18" SI woofers in it, but removed them for another project. Now I'm converting it to accept the new Stereo Integrity 24" monster driver they just came out with. I'll put another amplifier on it and likely run it from 40hz on down, Think that will do?

Only IB's will do :)

Can't wait to read the build thread on the dual 24's in the new IB.

I have a quad 15" IB that is awesome, but to balance out the modes in the room, I plan to install a second manifold in the rear and I am mulling over driver choices, that 24" driver is on the short list for a 2 driver config.
 

es347

VIP/Donor & WBF Founding Member
Apr 20, 2010
1,577
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Midwest fly over state..
I won't comment, I can only guess. ...From my own perspective.

Or perhaps "the most fun one can have of any activity while clothed". Phantom center channel? I don't see a center channel speaker..
 

16hz lover

Well-Known Member
Aug 2, 2013
234
15
70
Or perhaps "the most fun one can have of any activity while clothed". Phantom center channel? I don't see a center channel speaker..

I don't believe in them. Large front main speakers throw all the necessary sound in the middle already. 90% of all the center channel speakers are always too small to accurately reproduce gunshot blasts anyway. And as you can see, I have nowhere to put one....on purpose.:D
 

16hz lover

Well-Known Member
Aug 2, 2013
234
15
70

16hz lover

Well-Known Member
Aug 2, 2013
234
15
70
Only IB's will do :)

Can't wait to read the build thread on the dual 24's in the new IB.

I have a quad 15" IB that is awesome, but to balance out the modes in the room, I plan to install a second manifold in the rear and I am mulling over driver choices, that 24" driver is on the short list for a 2 driver config.

This is my IB box in the attic when I had the 4 Stereo Integrity 15" woofers in it. with the top off of it.
 

audioarcher

Well-Known Member
May 6, 2012
1,396
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970
Seattle area
You put the drivers on the wrong side; outside instead of inside the enclosure. Where did you learn on how to build a subwoofer? ...

Look up infinite baffle subwoofer and you will get it then.;) I don't know much about them myself but they are something I would like to try one of theses days. I assume he has the top cover off for the photo?

16hz Lover, How much do you have to eq these to make them work?
 

audioarcher

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May 6, 2012
1,396
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Seattle area
I'm also curious what kind of distortion specs IB subs typically have? Does it get close to servo controlled subs?
 

16hz lover

Well-Known Member
Aug 2, 2013
234
15
70
Look up infinite baffle subwoofer and you will get it then.;) I don't know much about them myself but they are something I would like to try one of theses days. I assume he has the top cover off for the photo?

16hz Lover, How much do you have to eq these to make them work?

audioarcher: Northstar was joking around, and yes the top cover was off for the photo. No EQ was necessary, and I was able to crack a drywall joint with that set-up.
 

JonFo

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Jun 11, 2010
322
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Big Canoe, GA
www.jonathanfoulkes.com
I'm also curious what kind of distortion specs IB subs typically have? Does it get close to servo controlled subs?

Having come from a pair of 18" Velodynes and now run a quad 15" IB, I can assure you the IB has very little distortion. The Velo's control distortion, but at the cost of headroom (they compress), the IB can hit very high SPL at super low distortion.

When testing my center channel (which is bolted to the top of my IB), I ran full range tests at 90dB SPL and the total system distortion was below 0.6% from 20 to 20Khz
Even at house shaking volumes, that IB Sub is uber clean.
 
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audioarcher

Well-Known Member
May 6, 2012
1,396
51
970
Seattle area
Having come from a pair of 18" Velodynes and now run a quad 15" IB, I can assure you the IB has very little distortion. The Velo's control distortion, but at the cost of headroom (they compress), the IB can hit very high SPL at super low distortion.

When testing my center channel (which is bolted to the top of my IB), I ran full range tests at 90dB SPL and the total system distortion was below 0.6% from 20 to 20Khz
Even at house shaking volumes, that IB Sub is uber clean.

Wow, that is impressive! Sounds like the way to go if you have a room that will allow this to be done. Unfortunately in my current room I have no way to do IB. In my next house I will definitely try to implement it though.
 

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