[pgwalsh]

Hi all!


This is/was my first build and probably more ambitious than it should have been.I definitely leaped in with both feet. It was fun, exciting and trying.


Maelstrom 21"

Russian Birch 3/4" and 1/2".

Volume is 10 cubic feet.

Size is 48" x 28" x 18.5"

an MFW-15 next to the Maelstrom.

Inside with wall lined with sound dampening material and polyfil. I wanted to test it before I covered it.

So at this point I tested the sub and unfortunately I ended up with a bad driver.

But I continued on with the project.

Staining russian birch is dumb. I wont do it again, at least not with a dark stain. Takes forever and the wood doesn't want the stain.

Final coat made it nice and dark.


Off she goes to the upholsterer.


and then she came back.

I don't have a working driver, so no numbers to post. I will be powering with a EP4000. This was my first time using a table saw or router, so it was definitely a learning processes. It definitely has WAF acceptance even though I only have a GF, but she play the wife role well.

I like the height and it is a beast, but it's comfortable to put my feet up on and when I did the original testing, it didn't vibrate much at all. I used a dark chocolate color that's a leather/faux leather mix. Interesting material, but feels nice and I think looks pretty good.

 

[Tack]

Thats a really amazing build. Fantastic work, too bad about the driver, hopefully something comes up.


Does the upholstery come off easily ?

 

[DS-21]

What a great idea, well implemented! Too bad about the drive-unit. How are you hiding the wiring from amp to sub? Cutting a hole in the area rug?


Seems a pity to let it sit unused, though. Have you thought about using one of the 21" B&C drivers? Less volume displacement and more EQ required, but should still work quite well. Assuming they're OK downfiring, at least.

 

[pgwalsh]



Quote:
Originally Posted by Tack /forum/post/20544559


Thats a really amazing build. Fantastic work, too bad about the driver, hopefully something comes up.


Does the upholstery come off easily ?

Thanks I really appreciate it.

No... All those little nail heads are holding it down, but the driver is on the bottom and is down firing. I wanted to tuft it originally, but that would have been too much of a hassle and would have required either adding 1/4 ply that would have to be glued on top of the 3/4 inch or poking holes in the 3/4", which wasn't going to happen.

Quote:
Originally Posted by DS-21 /forum/post/20544593


What a great idea, well implemented! Too bad about the drive-unit. How are you hiding the wiring from amp to sub? Cutting a hole in the area rug?


Seems a pity to let it sit unused, though. Have you thought about using one of the 21" B&C drivers? Less volume displacement and more EQ required, but should still work quite well. Assuming they're OK downfiring, at least.

Thank you.


I'm working on the driver issue, so I'm not currently looking at alternatives. I also don't want to create a thread about it since there's one already. Hopefully patience is a virtue.


That area rug is authentic, so I'm not going to poke a hole in it. Fortunately the amp is less than 10 feet away and I'll have a black runner on the rug. It'll be a bit of an eyesore, but I'm going to put a couch in the room and that will help hide it. The room uses Lutron lighting and the lights are rarely all the way on.

 

[Audiophile34]

that 21 inch woofer makes the 15 look like a toy!


amazing build man, really is. cannot wait to see some graphs! if it sounds at all a good a it looks, then I am truly envious...

 

[Archaea]

Wow - amazing for a first time build! My hat is off to you!

 

[Digity8]

As an ottoman do you have any localization issues?

 

[pgwalsh]



Quote:
Originally Posted by Audiophile34 /forum/post/20544725


that 21 inch woofer makes the 15 look like a toy!


amazing build man, really is. cannot wait to see some graphs! if it sounds at all a good a it looks, then I am truly envious...

Thank you. I'm looking forward to graphs as well. I have built 2 dual opposed with 15's that'll be in the front of the room and I will use a miniDSP to blend them together. I'll post pics of that project soon. Just need to finish the grills this weekend.

 

[pgwalsh]



Quote:
Originally Posted by Archaea /forum/post/20544740


Wow - amazing for a first time build! My hat is off to you!

Thanks... It took a really long time, really long. I started last year. Waited for my bosch router, the new one, but they had manufacturing parts issues and I finally got tired of waiting and ordered a the older model.

Quote:
Originally Posted by Digity8 /forum/post/20544744


As an ottoman do you have any localization issues?

Yes, I have some localization issues, but my girlfriend didn't notice it. I have my 2 dual opposed that I just finished and will be in the front and that may compensate, but we'll see. The cutoff is at 80 and the frequencies above 50 seem to allow me to locate the sub. However, I had that same issue with my MX-350. The mal 21 in 10 cubic foot box with the 2 dual opposed model well and the SPL is very good with one dual opposed, so I may be able to do something to eliminate localization.


Also, I almost always think I can locate a sub, so it could just be in my head.

 

[kryptonitewhite]

Whats wrong with her! I haven't heard of a 21" having the same issue as the 18's ring coming loose though I did notice they were both discontinued.


That freakin BLOWS! So sorry man. Nice build.

 

[pgwalsh]



Quote:
Originally Posted by kryptonitewhite /forum/post/20545051


Whats wrong with her! I haven't heard of a 21" having the same issue as the 18's ring coming loose though I did notice they were both discontinued.


That freakin BLOWS! So sorry man. Nice build.

She's a woman, to start.

Actually when I was first testing it, she got scared and ran out of the room. I wasn't even close to its full potential, but things were rattling. I can't wait to get all 3 subs up and running. They need an devil emoticon.

 

[notnyt]

very nice, what's wrong with the driver?

 

[kryptonitewhite]

Your going to keep running her with the 2 little boys? Why not just run the 2? Your 21" suffers from the known issue of the ring coming loose, right?

 

[pgwalsh]



Quote:
Originally Posted by notnyt /forum/post/20545102


very nice, what's wrong with the driver?

You can read about it here , but it's the same issue you had I believe.

I honestly don't want to rehash the issue in this thread.

Quote:
Originally Posted by kryptonitewhite /forum/post/20545110


Your going to keep running her with the 2 little boys? Why not just run the 2? Your 21" suffers from the known issue of the ring coming loose, right?

Like Christopher Walken said in James Bond, View to a Kill, more.. more power. I guess you could say, I built it, so I want to use it for what I intended. There may be other options if thing don't workout.

 

[A9X-308]

You could probably make a sub-baffle and manifold to hold a pair of opposed 12" units that you could screw into the existing opening. Plenum could b straight or angled (as second attachment) as needed to fit them in.

 

[BiGBADDABOOM]

I wonder how quad MFWs would work in this application. I believe 10 cu ft is perfect.


I guess it would take restructuring the bracing, not just a new "baffle".

A dual opposed glass-top coffee table with two drivers on top, two on bottom and a gap before the glass would be pretty hot for the visual, and inertness.


I guess we'd be talking about a cheap, large, rectangle version of Bosso's subs at that point though

 

[subpro]

Nice, thats one way to gain waf indeed.

 

[pgwalsh]



Quote:
Originally Posted by subpro /forum/post/20554637


Nice, thats one way to gain waf indeed.

No one can tell that it has dual purposes, they just think it's an ottoman, a big one.

 

[vitod]



Quote:
Originally Posted by pgwalsh /forum/post/20555602


No one can tell that it has dual purposes, they just think it's an ottoman, a big one.

Curious about wiring. Are cables going to be visible?

 

[pgwalsh]



Quote:
Originally Posted by vitod /forum/post/20558496


Curious about wiring. Are cables going to be visible?

I suppose they will be if you really look for them. It's a short run and I will use a cable runner.