dual 18" mael-x

[dem beats]

Title says it all. these will be 2 boxes with an internal chamber of 16 cubic feet. Tuned to 12hz. I got almost all the cuts done. Still need to brace, but those cuts will happen later when the basics are done.

Here's the first glued up joint!

 

[dem beats]

Someone told me you gents like pics too so I thought I would show you my best friend while cutting these up. Great tool.

 

[gmichael]

Yikes! That sucker is ganna be big! And hit pretty good too. What will you be driving it with?

 

[dem beats]

Yikes! That sucker is ganna be big! And hit pretty good too. What will you be driving it with?

Well, I'm short on power but I got the amp for a song.

It's a QSC PLX2 3102. It should put out ~1000 to each. I wanted to be giving them 1500-2000 but even with such *low* power it will be more than anyone needs.

My goal behind this was to give as much impact at 8-15hz as possible without going completely insane or building something into the house itself.

 

[adwilk]

What will you be driving it with?

Hopefully a diesel, geez... thats a monster...

 

[dem beats]

Hopefully a diesel, geez... thats a monster...

Bio diesel!

All I know is it will be a bit stronger than the velo I have now

 

[jostenmeat]

Well, I'm short on power but I got the amp for a song.

It's a QSC PLX2 3102. It should put out ~1000 to each. I wanted to be giving them 1500-2000 but even with such *low* power it will be more than anyone needs.

My goal behind this was to give as much impact at 8-15hz as possible without going completely insane or building something into the house itself.

Can you share/link more of the overall plans? Just curious. My Crown XTI2000 is plenty plenty for me and my single 23 cu ft (external) sub. Cheers, good luck, and thanks for the pics.

 

[Warpdrv]

Nice build....

Should give you plenty of output.... What size room ?

I assume your going for a forward - front facing driver array...?

Or are you going the dual opposed route to give you the added benefits of the inert cab..?

 

[Matt34]

If I build another sub it's going to be a dual opposed 18" Mal-X.

 

[Warpdrv]

Matt, the Mal's are great drivers as long as you don't have to push them really hard (ie big room), going dual opposed is a great design.... get a good amp like the OP did here, QSC's are great.

9-10 cu ft would be great, and give a little EQ boost to the low end you'd be golden. Unless you can handle a bit bigger box, then you don't need as much amp sucking EQ boost.

Dem Beats, you are really making a huge box for your build, any particular reason for so big.... The Mal's work great in small boxes, 6 cu ft was a very good size, which I used for my 3....

 

[dapack69]

Bio diesel!

All I know is it will be a bit stronger than the velo I have now

Is that the CRT 12?

 

[Warpdrv]

Edit.... I guess I didn't read as close as I should have, your building 2 ported boxes, those should be quite monsterous.

 

[MidnightSensi]

Can you share/link more of the overall plans? Just curious. My Crown XTI2000 is plenty plenty for me and my single 23 cu ft (external) sub. Cheers, good luck, and thanks for the pics.

Depending on where I look, that sub is around 88db/watt/m, your sub is 101db/watt/m. So, more or less, your subwoofer needs about a 1/10th of the power to achieve the same SPL (3dB extra sensivity requires half the power for the same SPL, and so on).

It also looks like the impedance is 3 ohms (also depending where I look)....

So, basically, you need some serious amplifier power to get this thing to move.

 

[dem beats]

Pics just for fun/teaser

Here is a look at the goods in various forms of undress.

Kitteh for reference. and

Amp T and A

 

[dem beats]

Is that the CRT 12?

Nope, just a DPS.

 

[dem beats]

Matt, the Mal's are great drivers as long as you don't have to push them really hard (ie big room), going dual opposed is a great design.... get a good amp like the OP did here, QSC's are great.

9-10 cu ft would be great, and give a little EQ boost to the low end you'd be golden. Unless you can handle a bit bigger box, then you don't need as much amp sucking EQ boost.

Dem Beats, you are really making a huge box for your build, any particular reason for so big.... The Mal's work great in small boxes, 6 cu ft was a very good size, which I used for my 3....

I wanted a build with at much power in the 8-12 hz range as possible. I know this build will have way more than enough raw SPL, but I want to have as much impact as possible at the extreme low hz. I'm using winISD online right now and it agrees with what I found earlier. I also think that they will sound pretty darn good with music so long as I have them matched well for 2 chan time.



Going with 16 cubic feet would have 4-5 db less roll off at 10 hz and it would be a flatter curve. It's more of an exparament really because I'm not that big into earth crushing output while actually watching movies, but this will help show what can be done while keeping the costs pretty far down.

 

[jostenmeat]

dem beats, do you know what 8-10 feels like? I don't necessarily know myself, but I've been learning some interesting things while playing with my Crown's EQ on my Danley. I might have read somewhere that B Fitzmaurice, or was it someone else, doesn't even think sub-20 is worth going for.

Anyhoo, I built a big EQ shelf at 30hz, and it didn't have the impact I was looking for. It was like a subtle pressure. Shelf at 45hz, daddy-o! Riser-a-shakin'. And btw, my sub is capable of going pretty low, perhaps not quite as low as the one you're building (though owners have measured usable in-room response down to 7-10hz), but I just wanted to bring up a point/query. IOW, are you sure 8-10 is really the goal to be going for here . . . If your sub is not extremely efficient to begin with, and you're chasing down the lowest subsonics, how much will you be giving up on the usable HT stuff? Remember, a lot of BDs are using 25hz filters anyways . . . . (I've read that Avatar, Master and Commander and LOTR all stop dead in their tracks at 25hz).

 

[gmichael]

Not for nuttin', but I'd never let my cat get that close to my 18" driver!

 

[darien87]

d
Anyhoo, I built a big EQ shelf at 30hz, and it didn't have the impact I was looking for. It was like a subtle pressure. Shelf at 45hz, daddy-o! Riser-a-shakin'.

Remember, a lot of BDs are using 25hz filters anyways . . . . (I've read that Avatar, Master and Commander and LOTR all stop dead in their tracks at 25hz).

Forgive my ignorance, but what is an EQ shelf?

Also, if that's true about BD's cutting off at 25hz that sucks.

 

[j_garcia]

Where did you read this, because Master and Commander's cannon shots sound just fine on my system and I am fairly certain that there is sound well below 25Hz on some of those shots.

I was at a friend's place this weekend and he fired up the THX thingy at the end of Avatar and his subs are geared for 25Hz. There wasn't much there, but mine easily rattles stuff throughout the house.