18” down-firing EGG shaped sub build…

[GMichael]

I ordered the driver, bought the wood, and will be starting the cutting this weekend. This will be a bit of an unusual build. Some will say that it will be ugly, but the wife has given her stamp of approval, and more importantly, I like it. It should be a nice step up from my current Titanic III 15”.

The driver will be a Maelstrom-18".
Amp will be a Behringer EP4000.
EQ will be a Behringer DSP1124P Feedback Destroyer.
Using ¾” MDF to make a 5.75 cubic foot sealed enclosure (internal).
Walls to start at 2” thick and then be sanded down to maybe 1&3/4.

I don’t have any graphics software but have managed to put something together with Excel & Word. Here is a cross section of what it should end up looking like. It will be 30” wide by 35.25” high. I have noticed that with Excel, dimensions will be skewed from one computer to the next depending on settings. The width should be 85% of the height, so if you want to see it scaled properly, you may need to do some stretching of it.

What do you think?

[audio amateur]

Awesome project, but why not use sonotube and make a cylindric enclosure? Would be much easier to make!

http://i61.photobucket.com/albums/h69/ecir38/LLT/37.jpg

Also, the sub's Qts suggests that it would work well (maybe better) in a ported enclosure. What program did you use to get that volume?

[GMichael]

Thanks AA,

A cylinder would not be as unique. This will be a one of a kind work of art. (And it gives me something to do while wifey & baby are out of town)
I checked out the graphs available from Kevin’s website. I like the in room responses for sealed. Besides, I’ve heard and built many a speaker. Sealed almost always sounds better to my ears. With 18” being driven by almost 2500 watts, it should be more than loud enough for me.

[audio amateur]

As long as you know what you're doing :thumbsup:
If you need any advice let me know.

[GMichael]

I could use someone to hold my wood while I cut it.:ihih:

[audio amateur]

Here are a few sub ideas just in case... :D

Rubix cube sub
http://dvice.com/pics/rubiks1.jpg

The Deathstar
http://hotimg23.fotki.com/a/91_114/228_36/DeathStarSubwoofer.jpg

A true dipole subwoofer by Elemental Designs
http://blog.evaria.com/wp-content/uploads/2007/09/dodecasub.jpg

And finally the monster RE XXX subwoofer driver
6868

[GMichael]

I like the rubics cube.

[JohnMichael]

GM maybe I have been around the medical field too long but it looks like a suppository.

[poppachubby]

The Rubix Cube is awesome, and they even solved it!

[kexodusc]

GM...that looks AWESOME!

You probably know this already...but especially for an 18" woofer. BRACE that cabinet.
Easiest is probably just shelf braces running across at 2 layers with big holes in them...don't make it symmetrical and you'll help break up internal resonances a bit too...

What are you using for damping material?

And how are you connecting the layers? Glue and brad nails?
Solid choice of amp. You are unlikely to ever come near clipping that jobber. You just using binding posts to connect it to the woofer?

Geez, I feel puny with only two 15" subs.:(

[GMichael]

GM...that looks AWESOME!

You probably know this already...but especially for an 18" woofer. BRACE that cabinet.
Easiest is probably just shelf braces running across at 2 layers with big holes in them...don't make it symmetrical and you'll help break up internal resonances a bit too...

What are you using for damping material?

And how are you connecting the layers? Glue and brad nails?
Solid choice of amp. You are unlikely to ever come near clipping that jobber. You just using binding posts to connect it to the woofer?

Geez, I feel puny with only two 15" subs.:(

Thanks Kex. I’m glad you like the design.

I was wondering about bracing. There are no flat walls that will be able to flex. I’m using all rings. Circles are much stronger than boxes. The walls will mostly be 2 inch thick except for a few that will be 4 inch thick. Will there still be a need for bracing? If so, I could just make one ring a solid disk and then cut a bunch of holes in it.

I will be using 2 inch Mineral Wool. The case of 6 is way more than I’ll need but I may find other uses for it around the house. http://www.atsacoustics.com/item--Roxul-Acoustical-Fire-Batts-Mineral-Wool-2-inch-Case-of-6--1006.html

Glue and screws. This way I will need minimal clamping for the glue to dry. Just normal yellow wood glue. Thinking of maybe 2 inch screws so each will help to hold 2 or 3 pieces together. I’ll drill and countersink first.

The amp should be good. Bench tests show it at 2400 watts RMS .1% THD bridged to 4 ohms. I’ll run it as is for a while to see if the fan bothers me before I attempt the fan mod. I’ve read that the EP4000 is the same as the EP2500 with minor changes, including a quieter fan. We’ll see.

Ordered these posts from PE. http://www.parts-express.com/pe/showdetl.cfm?Partnumber=260-314%20%20%20%20%20%20%20%20&FTR=260-314&CFID=25392236&CFTOKEN=93446984
And these T-nuts. http://www.parts-express.com/pe/pshowdetl.cfm?&Partnumber=081-1090

Also received 10 feet of BlueJeans 10 gage wire. That should be enough for my needs.

I believe that two 15” subs will outdue one 18” sub. No need to feel puny.

[GMichael]

GM maybe I have been around the medical field too long but it looks like a suppository.
Uh yeah.... It's because you've been in the medical field too long. That's what we'll go with.... :nonod:




What's my excuse?:ihih:

[audio amateur]

Kex, do sealed speaker enclosures generally need to be loosely stuffed? Does this also apply to sealed subwoofer enclosures?

[basite]

That looks like an awesome design indeed!

I agree with Kex though, brace it, brace it real serious!

what glue are you going to use to glue the layers to each other? whichever you use, be sure to do only 2 layers at one time, and clamp them, as good as possible, you don't want any holes in the glue...

btw, are you leaving the walls like that? or are you planning on using a filler of some kind (or cement, which might be more appropriate :p), to make it a smooth/real egg like enclosure?

Good luck, and don't cut your fingers of :p
Keep them spinning,
Bert.

[GMichael]

That looks like an awesome design indeed!

I agree with Kex though, brace it, brace it real serious!

what glue are you going to use to glue the layers to each other? whichever you use, be sure to do only 2 layers at one time, and clamp them, as good as possible, you don't want any holes in the glue...

btw, are you leaving the walls like that? or are you planning on using a filler of some kind (or cement, which might be more appropriate :p), to make it a smooth/real egg like enclosure?

Good luck, and don't cut your fingers of :p
Keep them spinning,
Bert.

Thanks Basite,

I will be cutting the disks at angles to match the curvature of the egg. Then lots of sanding. No filler.

I have 10 fingers today. My plan is to still have 10 fingers next week. Keep your fingers crossed for my fingers.

[basite]

Thanks Basite,

I will be cutting the disks at angles to match the curvature of the egg. Then lots of sanding. No filler.

I have 10 fingers today. My plan is to still have 10 fingers next week. Keep your fingers crossed for my fingers.


sounds like you have a plan :)

here's some more inspiration btw: link to an egg speaker! (http://www.6moons.com/industryfeatures/roadtourbrasschaat/speaker.jpg)

[GMichael]

sounds like you have a plan :)

here's some more inspiration btw: link to an egg speaker! (http://www.6moons.com/industryfeatures/roadtourbrasschaat/speaker.jpg)
Cool. I especially like the ports in the stand. Nice.

[kexodusc]

I was wondering about bracing. There are no flat walls that will be able to flex. I’m using all rings. Circles are much stronger than boxes. The walls will mostly be 2 inch thick except for a few that will be 4 inch thick. Will there still be a need for bracing? If so, I could just make one ring a solid disk and then cut a bunch of holes in it.


Well, I'll be honest, I'm not 100% sure how the fact it's a bunch of rings glued together will affect things as far as need for bracing, but I know a brace won't hurt. It's not the shape's ability to carry weight as much as the depth and density of the material. The pressure inside is going to make the cabinet want to resonate. The adjacent sides of the rings are coupled to themselves since they are circles so there's not really adjacent sides, but energy is transferred through each layer where connected by adhessive. I don't think bracing vertically is going to be effective or possible but a shelf brace is easy to do, just cut big holes like you said...in rectangular cabinets, they often look like window frames. I just make holes with jigsaw - they dont' have to be symmetncal or pretty.

But I have seen many formed MDF or similar curved shape MDF cabinets cut like the layered rings you're using, - and bracing is used in these designs- which leads me to believe it's a good idea or those builders are also playing it safe.

Besides, if small monitor and tower speakers are being braced with 5"-7" woofers, 18" subs probably need it too :). 18" subs with 30 mm of xmax move a lot of air compared to 5" woofers in 3/4" mdf boxes.

This is one of those better safe than sorry things. I know some builders that swear not to go more than 8" without brace. And bracing mattered big time in my first 15" sub which was 1.5" thick. I learned the hard way - it's easier to spend 15-20 minutes cutting and including a brace now, then adding one later once the box is sealed. The second cabinet I built I rabbeted spot for the shelf brace.

I think a brad nail or two while gluing each layer might not be a bad thing either, rather than just clamps, assuming you have access to a brad nailer.

Looks like you're well on your way though.

Edit: One last thing - having 1 or 2 shelf braces inside also should help make applying damping material to the walls a bit easier.

[JohnMichael]

Uh yeah.... It's because you've been in the medical field too long. That's what we'll go with.... :nonod:




What's my excuse?:ihih:




Seriously it looks like a great design. Here is a photo of the Magico Mini cabinet and they had an interesting way of creating bracing by not removing as much material from all the pieces stacked together.

[GMichael]

Seriously it looks like a great design. Here is a photo of the Magico Mini cabinet and they had an interesting way of creating bracing by not removing as much material from all the pieces stacked together.

OOooooooo.... Nice!

I like it.

I am thinking of just leaving a couple of the rings as full disks and then cutting a bunch of holes in them.

[kexodusc]

Kex, do sealed speaker enclosures generally need to be loosely stuffed? Does this also apply to sealed subwoofer enclosures?
I have never had luck heavily stuffing a sealed cabinet but a lot experimenting is needed usually to find just how much. I tend to use a mix of insulation, foam and polyfill/acousta-stuff.I think this could be a personal preference thing too...not much of an answer, sorry.

[GMichael]

Since a few people seem to think that I didn't have enough bracing, here is the new design. Who's going to come over and help me drag this thing up the stairs when it's done?

Is that enough bracing?

[GMichael]

Cutting begain last weekend. There were a lot of setbacks at first, but now it's moving along well. I have 15 rings cut and the rest have all been drawn out. Just need to connect the dots and then I can start stacking.

[audio amateur]

I'd wait for Kex's verdict but it looks good. Make sure the holes in the braces are large enough. I'd say cut out the equivalent of the surface area of the driver or more in each brace to allow easy air flow between the different compartments of the enclosure.

Keep it coming and post some pics if you can, me wants to see the beast in construction

[GMichael]

I'd wait for Kex's verdict but it looks good. Make sure the holes in the braces are large enough. I'd say cut out the equivalent of the surface area of the driver or more in each brace to allow easy air flow between the different compartments of the enclosure.

Keep it coming and post some pics if you can, me wants to see the beast in construction

The braces will look like wagon wheels. A solid center, 4 spokes, and a 2 inch ring/wheel. There should be plenty of room for air flow.
I do have a question though. Should I have the spokes from one brace line up with the spokes from the other braces, or should they be staggered to brake up the sound waves better?

[audio amateur]

You can probably go with either. As you say, if they aren't aligned they might help with standing waves. To what extent I'm not sure...

[GMichael]

Can an egg have standing waves?

[kexodusc]

You got that thing built yet? :)

[GMichael]

You got that thing built yet? :)
Smarty pants!

Any ideas or commrnts? (jokes not withstanding)

[kexodusc]

No, not really. Think you've got enough info to go ahead. If it doesn't work well, making a box is cheap and easy, so low-risk here. You've got far more patience than I do with the amount of cutting and sanding you're looking at. But pictures of this will spread all over the world, I'm sure.

[atomicAdam]

I could use someone to hold my wood while I cut it.:ihih:

Your wife doesn't have issues with another dude holding your 'wood'?

[GMichael]

Your wife doesn't have issues with another dude holding your 'wood'?
Or having it cut.....:nonod:

[atomicAdam]

Or having it cut.....:nonod:


At this point you might be too old to use it, I don't know? So having it cut might be some form of stimulation..:crazy:

Anyways - I wanna see photos (of the egg)!

[paulspencer]

I agree with the extra bracing. It's not so much that you need it and would have to add it later, with the shape you have and the thick walls you don't really "need" bracing at all. But I would always do bracing as it's the most efficient way to get a stiff box. With bass it's all about stiffness and there is never too much.

There is no need to "break up sound waves." Design your bracing for maximum stiffness and you should be fine. With a sealed box, it's not so much what goes on inside the box, but what gets out. There are two ways to get out of the box:

1. Through vibrating the enclosure - this is what most worry about and it's important, but not as much as
2. Re-radiating through the cone itself - this is controlled by the damping of the driver

The second is a much overlooked problem, described here:

http://www.rythmikaudio.com/re-radiation.html

Consider this. You have very stiff and thick walls - 2" right? They will be as solid as you can make them. Now you have an 18" light weight cone that is designed to be compliant so that it can efficiently create bass. Which do you think provides the easier path for sound to get out of the box? Here we are not talking about transmission so much as the sound pressure waves from inside the box placing dynamic pressure on the cone, just like an active driver will cause passive radiators to move. It is the same except the active driver has an electric motor which resists interference. The driver Qts indicates the ability of the driver to reject this influence.

[GMichael]

I agree with the extra bracing. It's not so much that you need it and would have to add it later, with the shape you have and the thick walls you don't really "need" bracing at all. But I would always do bracing as it's the most efficient way to get a stiff box. With bass it's all about stiffness and there is never too much.

There is no need to "break up sound waves." Design your bracing for maximum stiffness and you should be fine. With a sealed box, it's not so much what goes on inside the box, but what gets out. There are two ways to get out of the box:

1. Through vibrating the enclosure - this is what most worry about and it's important, but not as much as
2. Re-radiating through the cone itself - this is controlled by the damping of the driver

The second is a much overlooked problem, described here:

http://www.rythmikaudio.com/re-radiation.html

Consider this. You have very stiff and thick walls - 2" right? They will be as solid as you can make them. Now you have an 18" light weight cone that is designed to be compliant so that it can efficiently create bass. Which do you think provides the easier path for sound to get out of the box? Here we are not talking about transmission so much as the sound pressure waves from inside the box placing dynamic pressure on the cone, just like an active driver will cause passive radiators to move. It is the same except the active driver has an electric motor which resists interference. The driver Qts indicates the ability of the driver to reject this influence.

Thanks Paul. All great info.

I think the shape of the "box" in this case should help cut down on the re-radiating factor. What do you think there?
I also plan on adding 2 inch Mineral Wool inside. The driver manufacturer suggests a half fill.

Thanks for the link. I guess all those curved speakers (IE:B&W) are not just for looks.

Here are the specs on the driving I will be using.

Fs: 17.4 Hz
Le: 4.0mH
Re: 3.8 Ohms (Voice Coils wired in series)
Qms: 3.62
Qes: .42
Qts: 0.37
Mms: 525g
Cms: 0.16 mm/N
Vas: 313L
Sd: 1182 cm^2
BL: 22.9
X-max: 32mm
Pmax: 1500W
SPL: 87.8 db/1W/1M

[GMichael]

OK, I have been on vacation for a bit so I haven't been posting my progress here. On the bright side, I was able to get a bit done. Let's start it off with a pic of the scrap wood. What a frickin' mess. It's a good thing that honey was away for two weeks.

[GMichael]

Here are the good rings that will be put to work.

[GMichael]

Inventory had to be taken.

[GMichael]

A view of some of the stuffing, and one of the braces.

[GMichael]

Half an egg is better than none?

[GMichael]

Finally it's taking shape.

[GMichael]

To give you an idea of the size, that's a Honda CRV behind it.

[GMichael]

But I left room for the binding posts.

[GMichael]

Another view of the bracing.

[GMichael]

It looks good sanded down.

[GMichael]

After the primer, I stained it china red. It looks more orange than red to me. I put a coating of red oak after this but it hasn't dried yet.

[Feanor]

:aureola:
After the primer, I stained it china red. It looks more orange than red to me. I put a coating of red oak after this but it hasn't dried yet.
Wow!! Very impressive, GM. :thumbsup:

[GMichael]

:aureola:
Wow!! Very impressive, GM. :thumbsup:

Thanks Feanor. I know that you are or have been a bit of a DIYer. I'm glad you like it.
The base will end up black. I was thinking that with a 9&1/2 month old in the house, it's only a matter of time before something gets shoved under the driver. So I'm putting a netting like material around the base. It's made of a tough plastic so it should keep out the unwanted objects.

[JohnMichael]

GMichael I am impressed. Very nice work. Wow you can do other things with your hands, I mean besides holding your beautiful daughter. I am anxious to read your report on how it sounds.

[JohnMichael]

I think you have created Modern Art for the Chicago Art Institute.

[GMichael]

GMichael I am impressed.
That's what they all tell me.:p

Very nice work.
Thanks. It sure was a lot of work. If I had to pay me my hourly rate, I wouldn't have been able to afford me. Good thing I work for me for free.
Just don't ask me to repeat that. I think I tied my fingers in a knot.


Wow you can do other things with your hands,
Whatsyoumeanbythatwillis?


I mean besides holding your beautiful daughter.
Good save. Points for bringing up the baby. Always makes me smile.


I am anxious to read your report on how it sounds.
That may be a while. That last coat of paint is taking forever to dry. And it still needs several coats of clear-coat before it's ready for wiring.

[GMichael]

I think you have created Modern Art for the Chicago Art Institute.
I did save a few of those crescent moon looking pieces. A layer of clear-coat and they may look nice nailed to my deck.

[GMichael]

Finally it's taking shape.
Notice on this pic that it doesn't look like it will fit through the door? That's no optical delusion. It really doesn't fit. It's going to have to go out the garage door, up the desk steps, and in through the kitchen.

[JohnMichael]

That's what they all tell me.:p



Good save. Points for bringing up the baby. Always makes me smile.







Obviously not rep points I just checked.:cryin:

[GMichael]

Obviously not rep points I just checked.:cryin:
Sorry,

My gun is still jammed. :nonod:
"You must spread some Reputation around before giving it to JohnMichael again."

[basite]

That's great work GM!,

Congrats :), let me just say that your egg happens to work inspirational :p

btw, how long did it take you to sand it down?

(do I get rep point now too?)

Keep them spinning,
Bert.

[kexodusc]

That's freakin' awesome GM! Just freakin's awesome. Any idea of how many hours you've put in?

[GMichael]

That's great work GM!,

Congrats :), let me just say that your egg happens to work inspirational :p

btw, how long did it take you to sand it down?

(do I get rep point now too?)

Keep them spinning,
Bert.

Thanks.
Huh?
It took the better part of a day to sand it down the first time. I used a belt sander and used up 2 - 40 grit, 3 - 80 grit and 2 - 120 grit belts. Now it just gets hit with 220 between coats.

I'll see if my gun can point your way.

[GMichael]

That's freakin' awesome GM! Just freakin's awesome. Any idea of how many hours you've put in?
Thanks.
I'm not sure of the exact number, but I did take off all of last week, and the friday before, to work on it. Averaged at least 10hr/day up till last saturday (then paint & wait, sand, paint & wait ect..) So as a guess I'd say about 80 hours. My back is killing me.
I calculated the weight based on a sheet of MDF = 96 pounds.
96 pounds / (49" x 97" x 0.75") = 0.38lb/sq".
Took the diameter of each ring x 2" x 0.75 " and added them all up and it came to 135 pounds. That doesn't count all the rings that are over 4" thick instead of 2" or the bracing (or glue, nails, screws, or paint). This thing must be over 150 pounds before the driver goes in. It's a beast to work with. Can't wait to try to get it up the stairs.

[GMichael]

Sorry,

My gun is still jammed. :nonod:
"You must spread some Reputation around before giving it to JohnMichael again."

I've been spreading the love all morning, but still no luck. Sorry?:nonod: :confused: :blush2: :frown2: :cryin:

[audio amateur]

Holy Moly that's what I call dedication! The problem with me is that I become so anxious to hear the end result that I end up rushing the whole project and never getting the finishing done, lol.
BTW, how did you get all those cuts done? Do have the machine?
Good luck with moving it, and don't destroy your back!

[GMichael]

Holy Moly that's what I call dedication! The problem with me is that I become so anxious to hear the end result that I end uping rushing the whole project and never get the finishing done, lol.
BTW, did you get all those cuts done? Do have the machine?
Good luck with moving it, and don't destroy your back!

Thanks!
I still have the MKIII 15", so I don't mind waiting.
The cuts were done by a jigsaw. They took about a day and a half to finish.
Don't cha want to come help with the move?

[audio amateur]

Thanks!
I still have the MKIII 15", so I don't mind waiting.
The cuts were done by a jigsaw. They took about a day and a half to finish.
Don't cha want to come help with the move?
No doubt, it probably helps to have a good sub in the mean time.
I forgot to write 'how' at the beggining of one of my sentences. So... you really jigsawed all that? How did you get such smooth circles? Sanding?
I've had a couple subwoofer projects myself and making the cutouts with the jig was the worst part, and that was making a regular box which doesn't require many holes. An egg though :shocked:
I figure you've done the major part now so that's awesome and now you can look forward to moving it :D Sorry I'm not there to help...

[GMichael]

No doubt, it probably helps to have a good sub in the mean time.
I forgot to write 'how' at the beggining of one of my sentences. So... you really jigsawed all that? How did you get such smooth circles? Sanding?
I've had a couple subwoofer projects myself and making the cutouts with the jig was the worst part, and that was making a regular box which doesn't require many holes. An egg though :shocked:
I figure you've done the major part now so that's awesome and now you can look forward to moving it :D Sorry I'm not there to help...

I made up a compas to draw the circles and cut them freehand. With the right jigsaw, blades, and settings, it's not that hard. I tried using a router & circle attachment at first but it wasn't as easy as I had hoped. Ended up destroying the first ring and had to re-cut it.
The sanding was the worst part. Even with a belt sander it was a ton or work. The top wasn't so bad but once I turned it on it's side to sand the lower section, it kept trying to roll away while I was working on it. In all honesty, I don't think I did that great of a job on the lower area as I got tried of the BS and pronounced it done before it was finished the way I'd like.
I'm thinking of using moving straps to help get it up the stairs. I'll thrown a blanket over it first. Hope it doesn't end up crushing me. :idea:

[audio amateur]

I made up a compas to draw the circles and cut them freehand. With the right jigsaw, blades, and settings, it's not that hard. I tried using a router & circle attachment at first but it wasn't as easy as I had hoped. Ended up destroying the first ring and had to re-cut it.
The sanding was the worst part. Even with a belt sander it was a ton or work. The top wasn't so bad but once I turned it on it's side to sand the lower section, it kept trying to roll away while I was working on it. In all honesty, I don't think I did that great of a job on the lower area as I got tried of the BS and pronounced it done before it was finished the way I'd like.
I'm thinking of using moving straps to help get it up the stairs. I'll thrown a blanket over it first. Hope it doesn't end up crushing me. :idea:
Yeah, must have been a heck of a job!
Definitely try and get some male help on the day you move it. If that thing rolls down some stairs it will definitely leave a path of destruction.

[GMichael]

Yeah, must have been a heck of a job!
Definitely try and get some male help on the day you move it. If that thing rolls down some stairs it will definitely leave a path of destruction.

I'm just hoping that it doesn't destroy me. If it gets loose and comes down on me I'll be crushed like a grape.

[audio amateur]

Hence the need for male help:)

[GMichael]

I am ordering the EP4000 to power this puppy. It has XLR and/or 1/4 inch TRS input connectors. Obviously I'll need an adaptor to get from my LFE RCA to one of these inputs. Is one any better than the other? XLR vs 1/4 inch TRS?

Is this the one I should be looking for? http://www.parts-express.com/pe/show...number=240-438


Or is it better to go this way? http://www.monoprice.com/products/pr...seq=1&format=2
.
.
.
.

[JohnMichael]

Hence the need for male help:)



or a few stout lesbians

[GMichael]

or a few stout lesbians
I do know a few who could help. They live too far away though. Although, if I called, they would come. :devil: Seems like abuse of power to me though. I'm sure I can find someone local to help me. It's not a bridge until I get there?:idea:

[GMichael]

After trying just about every red stain known to man, I gave up and went to paint. Stain was nice in that it let me keep the rings, but it also kept all the patchiness that comes with staining the edges of MDF.
We still had trouble finding a paint color we liked. 3 times we picked out a color to have it end up looking nothing like the sample at the store. Eventually we found this textured color & paint. It is still not perfect and the spottiness is still there in the picture, but it’s hard to see in person. Besides, it’s the imperfections that make it a work of art. (That’s my story, and I’m sticking to it)
It does look kind of cool with all the gold sprinkles in the clear coat though. The picture doesn't do it justice. Once this dries, I’ll paint the base & legs black. Should come out nice.

[GMichael]

Just bought a set of these Forearm Lifting Straps to help me get my monster egg up the stairs. (but I got them cheaper than this site)

http://www.uline.com/Product/Detail/S-15838/Moving-Boxes/Forearm-Lifting-Straps

Got them here http://www.suntekstore.com/Forearm-Forklift-Lifting-Moving-Straps-As-seen-on-TV.html

[paulspencer]

Nice work GM! Came out better than I expected based on the drawings. I think it's way better smooth and the texture finish makes sense.

Regarding the connections, my preference is to diy the cable to the exact length required and use the connectors that you prefer - RCA on one end, XLR on the other. It's a neater solution than using adaptors. I have a pile of adaptors which are good for temporary hook ups, but when I finally choose where things will be, I make up a cable.

[kexodusc]

Wicked. That thing would creep me out in my HT..I'd expect some giant spider monster to crawl out or something. Well done, GM!

[GMichael]

Ordered the EP4000 today. B&H Photo is having a sale. For $320 I get to buy a new one with a full warranty from a company I know & trust. Free freight, no tax.
I did find these as low as $299, but after adding frieght it was almost the same from companies only offering a 15 day return.

[GMichael]

Wicked. That thing would creep me out in my HT..I'd expect some giant spider monster to crawl out or something. Well done, GM!
Or maybe something like......

[GMichael]

Nice work GM! Came out better than I expected based on the drawings. I think it's way better smooth and the texture finish makes sense.

Regarding the connections, my preference is to diy the cable to the exact length required and use the connectors that you prefer - RCA on one end, XLR on the other. It's a neater solution than using adaptors. I have a pile of adaptors which are good for temporary hook ups, but when I finally choose where things will be, I make up a cable.

Thanks. I bought this one. http://www.monoprice.com/products/product.asp?c_id=102&cp_id=10244&cs_id=1024404&p_id=4776&seq=1&format=2
I went with the 3 foot instead of 1.5 foot so I'll have room to slide the amp out if needed.

[L.J.]

Great job GM! Dinosaur egg huh....well I guess your first demo movie should be Jurassic Park :smilewinkgrin:

Cute kid BTW

[GMichael]

Great job GM! Dinosaur egg huh....well I guess your first demo movie should be Jurassic Park :smilewinkgrin:

Cute kid BTW
Thanks.

You mean this little munchkin?

[GMichael]

Has anyone seen Google's background for today? Eggs eggs eggs.....

[GMichael]

Well, this project has suffered another setback (or two). Nothing too bad, but it still delays the final rollout. (No pun intended)
After the paint dried, I had to roll it onto its side to paint the legs black. I didn’t want to scratch up my new paint job on the cement garage floor, so I decided to use the carpet scraps left over from when our house was built. The wife has them in front of the downstairs entrance for people to wipe their feet on. As I laid them down, I thought that she might get upset if I got black paint on them, so I flipped them over. After all, who would notice black paint on the underside of a scrap carpet? Too bad that it turns out that the underside of it has a very coarse nylon mesh. Paint job ruined! Start over….
I never did really find the color I wanted in a store. I had mixed two colors together to finally find something I liked. Mixing them together to find that same color a second time proved difficult. What I ended up with was slightly lighter and a little on the pink side of brown/red. But it was OK and I pushed on.
Last night, that paint was dry enough for the clear coat to go on. Wifey loved the look of the clear coat with the gold sparklies in it last time, so I went that way again. This time though, the sparklies didn’t go on even. Must have been because of me reusing the same paint roller as last time. So now, I’ll have to repaint again. Shoot me now SHOOT ME NOW!:mad2:

On the bright side, the amp showed up. It’s a beast! It’s about half the size of my AVR but weighs about the same. Can’t wait to hear this thing, but wait is what I’ll do. Gotta stop at Lowes on the way home to pick up more red Mahogany and gold sparklies. (oh, and another roller)
:19:

[audio amateur]

Thanks for the update keep it up!

[GMichael]

Painted it again last night & took pics. The pics were loaded into Picasa but for some reason that folder doesn't show up here at work. I'll have to check to see if I didn't save it or something when I get home.
It looks pink now, but it looked pink the last two times as well. Once the paint dried it was more of a brownish red. Hoping for the same result this time.
Still not sure how I'm going to get this monster up the stairs. Been looking into renting one of those stair climbing dollies but haven't found one that suites my needs online.

[GMichael]

The paint dried. Last night I slapped on a layer of clear coat. Here is what it looks like. Once this dries it’s time to drag this bad boy up the steps. Once upstairs I’ll wire it up and add the driver. The last step will be adding black speaker cloth and it will be done.
Sure hope it ends up being worth all this effort.;)

[GMichael]

A couple more pics.

[GMichael]

One with a view of the terminal holes.

[GMichael]

Saturday morning I wrapped that rascal. First the cloth that my Onix Mini's came wrapped in. Then some plastic insulation that I use for the A/C units in the winter. Then the bubble wrap that the amp came in. Laid out the straps and I was ready to go. In the end, I ended up tying it to the hand cart and dragging it up the stairs. My back and legs are still killing me, but up the stairs it went.

[GMichael]

There was some damage though. Good thing it's on the back where no one will ever see it. There was no way I was repainting.

After getting it into the living room I needed to add the driver. I shouldn't have made the tolerances so tight. After struggling to get the driver to line up for several minutes it finally dropped in. Too bad my fingers were still in the way. Didn't slow it's 50 pounds down one bit though. I'm sure that nail will grow back eventually.

[GMichael]

It's quite a bit bigger than my Dayton 15" sub. Funny that it's called the Titanic. It seems so tiny now.

[GMichael]

It looks good in it's final resting place. It's not a perfect match to the Mini's but I did the best I could. So far it's not calibrated but I can tell that there are subsonics that weren't there before. I demoed Transformers 2. I could feel shaking that wasn't there before. It seemed to lack a little of the upper punch that the Titanic had, but that could be due to the lack of calibration. It certainly is more reserved for music but hits harder down low. Next weekend I'll pull out the Db meter and a test CD to see if I need a BFD. Still haven't decided if I want to put the Titanic to work behind the couch or not. We'll see.
For now, I'm very happy with how it's turned out.

[Feanor]

It looks good in it's final resting place. It's not a perfect match to the Mini's but I did the best I could. So far it's not calibrated but I can tell that there are subsonics that weren't there before. I demoed Transformers 2. I could feel shaking that wasn't there before. It seemed to lack a little of the upper punch that the Titanic had, but that could be due to the lack of calibration. It certainly is more reserved for music but hits harder down low. Next weekend I'll pull out the Db meter and a test CD to see if I need a BFD. Still haven't decided if I want to put the Titanic to work behind the couch or not. We'll see.
For now, I'm very happy with how it's turned out.
I should think so, GM. It's all looking good.

[bobsticks]

Smarty pants!

Any ideas or commrnts? (jokes not withstanding)

I think you gotta paint Mork from Ork on the side...

Ooops, I meant "nice design" GM!

[audio amateur]

After all that work I sure hope it lives up to your expectations. Are you going to equalize it? Sealed subs tend to have an early roll off which means boosting the lower frequencies (usually 30Hz and under) to achieve a flat low end is almost a given necessity. With that surface area and the power behind on tap you should have plenty of headroom to allow for EQ.
Now, you need to play 'Bass, I love you' - Bassotronics (heavy sub 20Hz content). Actually a very enjoyable song to listen to, and with flex your woof like no other. I can send it to you via email. SVSubwoofers have selection of films in their FAQ that contain serious bass also.
If this doesn't get you in trouble with your neighbours, nothing else will:-)

[GMichael]

Thank Feanor. It sure was a ton of work. I can finally start working on the yard.....

[GMichael]

I think you gotta paint Mork from Ork on the side...

Ooops, I meant "nice design" GM!

Nanoo nanoo...

[GMichael]

After all that work I sure hope it lives up to your expectations. Are you going to equalize it? Sealed subs tend to have an early roll off which means boosting the lower frequencies (usually 30Hz and under) to achieve a flat low end is almost a given necessity. With that surface area and the power behind on tap you should have plenty of headroom to allow for EQ.
Now, you need to play 'Bass, I love you' - Bassotronics (heavy sub 20Hz content). Actually a very enjoyable song to listen to, and with flex your woof like no other. I can send it to you via email. SVSubwoofers have selection of films in their FAQ that contain serious bass also.
If this doesn't get you in trouble with your neighbours, nothing else will:-)
Thanks.

I'm thinking of a BFD. A friend told me that he has an "extra one" whatever that means.

My nearest neighbour is through the woods. I don't think he can hear anything I do.:wink5:

[kexodusc]

Well done, GM! Any noticeable differences in sound from the Titanic other than output and extension?

[GMichael]

Well done, GM! Any noticeable differences in sound from the Titanic other than output and extension?
Thanks Kex,

Yes, I have noticed a difference right away. It has much lower extension than the Titanic had. It's not calibrated yet so it's hard to know what the overall sound will be when I'm done. Here is what I measured last night. It wasn't so easy to get these numbers. Ever try to explain to a 10 month old that she needs to be quiet while Daddy plays with his Db meter?:shocked:

[kexodusc]

Ever try to explain to a 10 month old that she needs to be quiet while Daddy plays with his Db meter?:shocked:
Is that what you call it? Really, you shouldn't be subjecting her to your adult extra-curricular activities. :ciappa:

[GMichael]

Is that what you call it? Really, you shouldn't be subjecting her to your adult extra-curricular activities. :ciappa:

So much for my dad of the year award.

How do you like that spike at 31.5 htz?

[kexodusc]

My guess is it's related to one of the dimensions of your room.
Honestly, your measurmenets are way better than any of my rooms have been before treatment and EQ...so not bad

Did you take measurments at 1/6th ocatave frequencies?
Usually I see BFD charts with measurements at: 16, 18, 20, 22, 25, 28, 31.5, 36, 40, 45, 50, 56, 63, 71, 80, 85, 90,100 etc...

In my case, you'd be surprised how many suckouts or peaks you can find in between these even...but at some point you just gotta move on.

[GMichael]

My guess is it's related to one of the dimensions of your room.
Honestly, your measurmenets are way better than any of my rooms have been before treatment and EQ...so not bad

Did you take measurments at 1/6th ocatave frequencies?
Usually I see BFD charts with measurements at: 16, 18, 20, 22, 25, 28, 31.5, 36, 40, 45, 50, 56, 63, 71, 80, 85, 90,100 etc...

In my case, you'd be surprised how many suckouts or peaks you can find in between these even...but at some point you just gotta move on.

Yeah, I figure it's the room too. It's a very noticable peak.
My Rives disc only produces the frequencies on my graph. What are you using to get all those 1/6th ocatave frequencies?

[kexodusc]

Oh, over at the HTShack, the BFD guide has a link to test frequencies you can download...don't have the link handy but Googling BFD guide should suffice.

[GMichael]

Oh, over at the HTShack, the BFD guide has a link to test frequencies you can download...don't have the link handy but Googling BFD guide should suffice.

Download? Uht oh. You mean to a CD or something? I have no laptop to speak of. Could the PS/3 download it you think? Or would an Ipod work?

[kexodusc]

Download? Uht oh. You mean to a CD or something? I have no laptop to speak of. Could the PS/3 download it you think? Or would an Ipod work?
Hmmm, I think they are just mp3's so the PS3 should work fine.

[GMichael]

Thanks!

I'll give it a try this weekend.
Just ordered a BFD from a friend on another sight. $60 shipped. He said he bought two but ended up changing his system and only needing one.

[audio amateur]

There's a tone generator with WinISD. Would that work?

[GMichael]

There's a tone generator with WinISD. Would that work?

Thanks. I'll keep exploring options.
I just read through the whole BFD guide last night. Why do I feel so overwhelmed? Seriously, calibrate my sound card? It may turn out to be easy, but it sure is wordy.

[L.J.]

Well? Have u got the BFD set up yet? Did u ever get those tones downloaded?

[GMichael]

Well? Have u got the BFD set up yet? Did u ever get those tones downloaded?
Hey LJ!

The BFD did come in. I set a few filters manually based on the initial results I had. In theory, it should be a pretty flat response now. When I went to check it, the Db meter was flucking up. It was giving me numbers below 50 Db for frequencies that I could clearly hear rocking the house, and then 90+ db readings for frequencies that were more subdued. I ran the tests several times and got different answers every time. It does sound good though. At this point I can only hope that it is at least close to flat. Eventually I’ll buy a new meter, but not at this time. Baby’s gotta eat.

When I run the test tones, I can hear/feel tones down to 10 hz. It seems to reach very low. As it goes through the tones, volumes increase until it hits 16 hz, and then it seems to slowly drop off a little at each tone. When I get a new meter (or if someone comes over with theirs) I’ll post new numbers.

[GMichael]

Here was the last result before the BFD. I ran this test several times and got the same numbers +/- 1/2 db.

[L.J.]

Wow, pretty easy start. Looks like a few filters were plenty.

Well if your Titanic starts collecting dust (cough cough) I would be willing to accept donations ;)

[GMichael]

Wow, pretty easy start. Looks like a few filters were plenty.

Well if your Titanic starts collecting dust (cough cough) I would be willing to accept donations ;)
Thanks.

I ended up with 5 filters. None of them are more than +3db or -5db. It sounds right, but it's only guesswork until I can get a new meter.

I noticed that the BFD can have two filtered outputs at a time. The Titanic might end up behind the sectional with settings all it's own. A little extra bass never hurt anyone.

(that i know of)

[L.J.]

Thanks.

I ended up with 5 filters. None of them are more than +3db or -5db. It sounds right, but it's only guesswork until I can get a new meter.

I noticed that the BFD can have two filtered outputs at a time. The Titanic might end up behind the sectional with settings all it's own. A little extra bass never hurt anyone.

(that i know of)

Wish I had room for 2 subs :prrr:

[GMichael]

Wish I had room for 2 subs :prrr:

It was all part of my master plan. 5 years ago, when we were looking through floor plans for our house, I picked out the one that gave us a huge living room. The closets and bathrooms are a little small, but the living room and master bedroom are nice.:thumbsup:

I love it when a plan comes together.
:14:

[Dual-500]

Absolutely cool! Be sure and post objective performance results. Nothing like a good, one of a kind audio project.

I run a single 18" sub in my system for now. Will morhp into a 4x18" in the next year or two. After running 18's there is no going back.

Beautiful wood work too. You have the skilled hands of a craftsman.

I'd be inclined to use some filler in it - experiment with that in real use. The mass of air within it will have resonance as a Vas only. Reflected energy should be nulled out by the shape.

Filler could actually enhance the lower extreme performance in this setup.

[Dual-500]

Interesting chart from the BFD. How does it work? Does it sweep a single tone or a more complex waveform like pink noise?

Tuning from a pure feedback point condition has it's limitations in a dynamic environment. That being mentioned, for theatre it could be a good way to go. What about the rest of the system? Any electronically assisted tuning there?

Not criticizing - just wanting to open up some discussion on the equipment and how it works.

[GMichael]

Interesting chart from the BFD. How does it work? Does it sweep a single tone or a more complex waveform like pink noise?

Tuning from a pure feedback point condition has it's limitations in a dynamic environment. That being mentioned, for theatre it could be a good way to go. What about the rest of the system? Any electronically assisted tuning there?

Not criticizing - just wanting to open up some discussion on the equipment and how it works.

Thanks. It was a h.ll of a project. I still have a smashed fingernail to prove it.

The BFD software I found can do a sweep, but I don’t have a laptop to run it in the HT room. I burned a CD of test tones ranging from 10 Hz to 143 and used a Db meter.

The rest of the system is as follows:

Yamaha RX-V2500 AVR (Auto set-up ran, but EQ re-set to flat)
Onix Strata Mini for the mains. (Planner hybrids with built in subwoofers: The subs are set at less than half power with crossovers set to 100)
Infinity Primus center, surrounds and rears.

[bobsticks]

This thread is awesomely surreal. I tried to give you Greenies but was denied.

I love the absolute commitment and attention to detail...on the egg!. Every additional post in this thread makes me happy. Thanks for sharing GM!