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BUILD LOG 990 cubic feet (2)18.25"x8.25"x2" ports 9Hz tune Twin Towers come down

21K views 165 replies 8 participants last post by  Andrew Mason 
#1 ·
I have decided to take Thomas-W's advice and build a manifold on my door to house (4) Fi IB3 18's on the top and make 2 slot ports on the bottom out of the rectangles already there. The door is 1.25" thick, I will make a template/face of the entire door adding .75" to the thickness. I'll make a 25"x25" panel to plug the ports so I can run true IB as well. Here is a pic he suggested for me.

Go to Home Depot buy a cheap solid core door, do something like this .......



I will begin tearing the Twin Towers down tomorrow and use the wood to build the manifolds and ports. It will be nice to get the EP4000s out of the HT room cuz I haven't done the fan mods.

The IB3s are custom dual 4 ohm, 4 layer IIRC, series/parallel 4 ohm bridged per EP4000 (2 EP4000s, 2 subs per amp bridged).

I am wasting and tearing apart a very wonderful performing pair of enclosures. Under 10% THD these things hit 124dB @ 10Hz and 130dB @ 23Hz. If I would have braced them better that 25Hz-40Hz would have been fixed. They were 125 cubic feet each with a 12" port 12" long for a 13.4Hz tuning, 2 IB3s per tower.





Here is the Twin Towers build log:

http://www.avsforum.com/avs-vb/showthread.php?t=1231247
 
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#3 ·
Ideas are constantly filling my pea brain, I'll try to update as much as possible. Under the door needs sealed up so I will have a larger piece of 1/2" MDF in the doorway bottom with a 2x4 glued and screwed to it to complete a full rectangle door jamb with weather stripping to make an airtight seal and prevent buzz and rattle.

The closet in the spare room is well over 10 cubic feet so this will actually be over 1000 cubic feet. When i build the double layer manifold, the outter layers will be extra long to add strength to the entire door... the manifold itself and 4 18's will be quite heavy... but more so to help prevent cancellation.

I have an idea and a little experience that larger fatter ports that i use since I love huge airspace creates unloading and cancellation much more than smaller longer ports. There are SPL setups in vehicle "walls" where there is actually not a wall. About 1/3rd of the "wall" is subs mounted in several layers of mounting rings, but in between each sub it is cut out... more port area..each subs mounting rings are only as wide as the mounting flange itself. The other 2/3rds of the "wall" is port as well. Basically they have 10-20 subwoofers all on a horazontal plane but nothing in between them, acting as port, and to the side all open. This creates an ultra high tuning in the 70Hz - 80Hz range with an enclosure volume from 20-50 cubic feet. When they go below 70Hz I believe they unload quite a bit more than a guy with one sub in 3 cubic feet with a 4"x4" port 30" long when he plays below his tuning.

So anyway, I believe my bringing the sides of the manifolds all the way down to the bottom of the door and extending the bottom of the manifold out a ways will somewhat act as a port itself, cupping the actual ports. I believe I will end up tuned below 8Hz when this is all done.

Today I will set my REW mic stand back up, reinstall REW, then make my final Twin Towers video, a request from Graham. I'll make the vid, run a few sweeps as it is, then I will cut the ports out...leaving the ports 12" diameter x 3/4" length and run a few more sweeps. Ive had threads discussing whether extremely short port lengths with very large diameters fully function, and if yes or no, does this change with output levels...maybe at low volume it works but at moderate and high levels it does not.

I am afraid that over 1000 cubic feet, with 2 2" long ports with a lot of area, will not really act like ports. I am also worried that with them being so large in area but so short with all 4 subs mounted right next to them, cancellation and unloading will be a big problem.

FINAL PICS OF THE TOWERS:













hopefully those pics last a little while before bandwidth runs out. With the new project drawing more attention, as views and hits get high I get emails that they will be disabled for 30 days. Happens a lot on weekends and holidays.
 
#4 ·
I can't tear them down now. I'm getting more 12" tube, more caulk, and more 2x4s.... plus I gotta do something to my room but i don't even know where to begin. I'm gonna go back to 48" port lengths 6.5Hz tune and slowly chop them shorter if I can't handle the reduced output traded for single digit extention.

Graham made a great suggestion to make a vid of this track, Ive done it before. I haven't pushed the Towers much for quite a while

now, sold all my DVDs and Blurays cuz they all just got old, my PC sucks... I dropped $$$ on a Radeon HD 4550 7.1 surround sound

HD card to watch Netflix and HULU in surround, but I only get 2 channel output from the card so I have to turn my mains and

surrounds all the way sown and my subs all the way up to get anyoutput and it's weak. I was gonna tear them down today, was

testing out the track to find my limits, and the fan blades started spinning again..Ive never been able to catch that on

camera...not just bouncing but spinning. Now I remember how much output I get and I am afraid to tear them down now :( IDK what to do!

 
#5 · (Edited)
Well I never planned on using the mic in the house anymore cuz I swept, reswept, tried it with heater and all lights on, kitty sitting in the LP to see if his fur soaked up deebeez... I got mic'ed out so i tore the rig apart and rebuilt it for the van. Well I wanted to lay to rest the large port diameter short port length problem, planned on doing a sweep before I tore the ports out, then a sweep after I ripped the ports out...then tear the towers down.

I haven't dropped the hammer on the volume knob in a while..WOW I forgot how powerful there are. I can't do it. I'm sorry, but i jsut can't. Since I have the rig all set up, I may as well do a sweep anyway. So it is in my head now notnyt and Bosso, I got it... I am good to 9Hz then I am DEAD. This sweep clearly shows it.

I am going to get 2 more 12" x 48" sonotubes, rip these ones out, add bracing to fix the buzzes and rattles and that terrible suck out from 25Hz-37Hz.... and retune to 6.5Hz again. This time I will take my time now that I know better instead of listening for a few minutes then cutting the ports shorter. If I like it, if I can deal, I will stay tuned to 6.5Hz.... but i suspect I will raise it to 9Hz or so.

I'm gonna tear the rig down and go run REW in my van some more, see if flipping the phase on the 6.5's helped and I raised the level on the 4.5s and tweets. Hopefuly I can get the front stage tweaked, my sub amp should be back any day, then I can phase shift the subs and get it all flattened out :)



 
#6 · (Edited)
Put the 2 towers in that room then turn it into a folded horn make the door a speaker grill. That way you keep the boxes and just frame up some dividers. I thought I had a small space. How bout some stories about what people outside of that room have said, thats what I want to hear. BTW girlfriends a keeper if she likes those boxes.
 
#7 ·
lol Ive considered converting to tapped horns, same size, the IB3s just dont have the motors to do it. over on AVS they are still horn-crazy but nothing is coming out of giant ULF horns yet other than the DTS-10 and Housewrecker 11Hz Kicker horn.

I'm not abandoning this build, I am just slowing down and being more cautious. After making those vids today it reminded me just how much output I already have, just dont use it much. I want more in the single digits which means a huge sacrifice in the double digits and IDK if I am willing to make that trade. I'm going to brace and tune to 6.5Hz for a while and see if I like it. If I can deal, then I make continue this build to shift the FR to get more down low with more airspace.
 
#8 ·
I'm not abandoning this build, I am just slowing down and being more cautious. After making those vids today it reminded me just how much output I already have, just dont use it much. I want more in the single digits which means a huge sacrifice in the double digits and IDK if I am willing to make that trade. I'm going to brace and tune to 6.5Hz for a while and see if I like it. If I can deal, then I make continue this build to shift the FR to get more down low with more airspace.
 
#9 ·
I tought brandy how to run REW today so that she can run the sweeps on the PC while I adjust the volume on the receiver so we dont bottom with the ports cut out then with the new ports in. Tomorrow we're getting 2 sonotubes 12"x48" for 6.5Hz tunes. We will run compression sweeps in 5dB increments from 40dB to 15dB then 1Hz to 14dB, 13dB, and 12dB... I have gotten to 10dB without hard bottoming but I dont push the new subs like I did the reconed subs.

Then I will cut the ports out, run more sweeps, put the new ports in and run more...overlay them all.

REALLY FUN VIDEO of us running sweeps with REW and sine waves with NCH Tone Generator to see how bad flex is, where it is, what we need to do to fix it, and getting an idea if we can fix all the room flex and noises. 4 ported 18s in a tiny room gets very annoying tuned so low. I am at a breaking point of just getting rid of it, or attempting to fix the towers (theyre actually not that bad, all of the noise is the room, not the enclosures) as they lose a lot of output from 25Hz-40Hz from flex.







So we have an idea what to expect if the 12" x .75" port actually works

fr



spl



x



if I like the 6.5Hz tuning, we will most likely enjoy the towers for a while longer, get more wood, build the manifolds and ports onto the door, then swap the subs...leaving the towers up just in case.

KW
 
#10 ·
I forgot about sealed up. I have 2 16.5" cutouts for the 2nd subs, I'll stick a 2x4" though each port after we sweep with .75" port lengths, turn them float against the wall over the port from the inside, and bolt the 16.5" circles over the 12" holes to seal the towers up and run sweeps sealed.

Also I will try to get the sliding door track so I can shut the vault for the sweeps. All sweeps lately have been with the vaulted door open as I dont ave the track yet.
 
#11 ·
'' The ceiling fan already fell out before, "
LoL, :hide: at this point I would just tear the ceiling out and double layer green glue it back in put some patio tiles in each speaker for rocking and turn off the lights before the cops come.:devil:

Love this thread cause if anyone ever bugs me about my little 54"x24" Sonosub I can just send them here! Dude, your like one of those Rat Fink cartoons only with amps and subs.
 
#16 ·
im betting that the spare room is gonna have a much better fr than the HT room and i end up building another bed and setting up in there. Ill be boarding up both windows in there so the enclosure "seals up" better, there's only a small closet and the one door that will be the manifold/port. It's a touch over 1000 cubes with the closet open. The HT room is 1400 cubic feet, has the SR door, front door, and entryway vaulted door as well as 2 windows that are also to be boarded up.
 
#17 ·
As you mentioned boarding up windows and moving the bed in there it suddenly struck me your building a death trap in the event of a "electrical" fire or whatever. On the other hand you should be safe from zombies, but in either case get a nice Axe and create a escape plan just in case.

Last thought get a your should be able to wipe out a mile radius easy.
Now your ready for anything!
 
#18 ·
no joke this axe and short tire iron sit behind my door 24/7! I live in a bad neighborhood and have a 12 year old to look out for just in case, last year I had lots of vandals, even cut power to my house once!



But we would be able to get out through the port :p unless of course the fire is on the other side of it :( in which case a 7Hz sine wave otta "HULK-SMASH" it out!
 
#19 ·
So I am back on my messed up schedual, up all night sleep all day. Yesterday AM I was all gung hoe to tear the towers down before Brandy went to work so I could clean the carpets then build the manifolds. I lasted till 11AM then crashed. As usual thats when she got up, went and bought fuses so we had lights again, then she went to work...I was out cold till 12AM, she got home from work, now she ready to watch a few episodes of Lost then go to sleep. I made a pot of coffee, I will be up all nite with nothing to do. Gotta make it till Don shows up so I can fix his power wire, then I will crash all day, she has the day off...ugh!





like I said, she gotta watch Lost...






So I always find myself trying hard to make something work, like worried if I superglue my cubes to my towers they will just fall off. But when I want to ge them off, they wont come off. I had to POUND and pound the speaker, it flew to the floor and a tiny piece broke inside, now I get to take internal pics of my L/C/R/surrounds ;) Some day i will get Bob's dual FR125S w/quasi crossover and tweets kits...till then...





YUP, thats 6ohm 10W!



 
#20 ·
So no work getting done here, Brandy and Austin are out cold... he just turned 13 today... kittys are sleepin, so I am here again talkin to myself hoping for other night owls like me. Thought I'd share this thread that someone started over at ROE today. It makes all this I do worth it, all the negative responce I've gotten over the years all disappears with the good things like these:

" You know you're Kryptonitewhite when... "

http://forum.realmofexcursion.com/off-topic/72145-you-know-youre-kryptonitewhite-when.html

Here's a few exaples, made my night.

You tow behind you a mobile home to fit 3,000 cubic feet of space for IBs.

You've got more horsepower in amplifiers than you do in your vehicle.

The Franklin Mint calls you and says we need some 1/0 so we can press pennies this year.

Your subwoofer towers were a full size replica of the World Trade Towers, and weigh as much as them.

You have stock in lumber for doing a new build every 6 hours.

You come up with new numbers because your cone area is so great.

You can hear a sub bottoming out from 3 miles away.

When you're walking through Home Depot you look at a door and say "I can fit 6 18's on that door".
when you have guests over and you open the front door to let them in and say welcome to my subwoofer enclosure subs are straight ahead bathroom around the port and to the right.
LOL

Instead of using a towel for hands, you press a button and a 30 hz tone dries them in 8 seconds with a 12 inch port in the bathroom.
you know your kryptonitewhite when fbi shows up at your door questioning you about the earthquakes in japan.
When your building a box and someone asks you if your framing up a house.
When the expandable foam company calls you to ask what your daily order is.
When they keep recones on an auto ship program set for every week.
When you don't even consider a box until the numbers are triple digit cube counts.
You buy 64 ohm subwoofers by the warehouse.

You change T/S parameters quicker than most of us change our minds.
When you do sound sweeps 15 times as much as you sweep your house.

When Winsid sends you a plaque for the highest graph count.

When you attach a camper to your vehicle as an enclosure.
when a subwoofer company needs to change its lineup because of your youtube videos.
When the termlab measures your gear in KPL, Kryptonite Power Level
He plays a sweep, and someone in a neighboring county says "Pardon me"
Ur install sounds good from 20hz and down..
Anything above sounds like a dogs whistle
Audiopipe came out with a new line, AudioWhite.


when your volume size has a E sign. To the 12th power!
I got all skeered when I saw the orange name pop up, but now I'm in the clear.

Kryptonite's headphones are a 3 way setup consisting of two 15's, a 6 inch and a ribbon tweeter. Each. Each side is feed 1000 watts.
and each side in a 300 cube box
when your sub has enough excursion be deadly to anyone near the woofer
when you have so much pressure generated by your system that you cause an implosion and spawn a mini black hole


when you dont need an AC for the summer just put on some 30hz tones to cool off.
when your neighbor a block away calls an asks what your watching cause it sounds like a good movie.
i try lol,

when you dont have to get up to get the remote, just turn up the HT an have it vibrate to your hand.
When you stand in front of your latest sub and feel like one of the little people.

When Dubai calls you and asks your ideas for the latest island.

When you make Godzilla cry.
When you buy 2 dc lvl 6 18's because the motor force will help alot with single digit frequency reproduction........ oh wait thats when your me :D (but i blame me on krypto sooooooo it fits)
 
#23 ·
All the talk in the beginning about "how are you gonna move them?" All these guys saying "it's gotta be this light and only this big so 2 guys can move it". Brandy just had to ask if I had anything to say. Hah. Wromg thing to ask.

Twin Towers Come Down, me moving tower 1 all by myself.

 
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