Another Sealed Mal-X Build

**Navydoc** · **05-25-09, 07:16 PM**

Finally finished construction of my 24" sealed subwoofer (NEOdan's cutsheet). Since the MAL-X will not be available for a few more weeks, there is no rush to complete the build so I added extra side panel bracing (primarily as an alignment aid). No screws were used on the external surfaces of the box.

**Navydoc** · **05-25-09, 07:33 PM**

Now that the subwoofer box has been built the hard (i.e. not fun) part begins - sanding and staining. Box was constructed with birch plywood (3/4") and I will add oak trim pieces (3/4" x 2 1/2" x X) to mimic a mission style build. My plan is to stain the birch and the oak trim, if they do not match will have to add veneer (red oak). Unfortunately a screw head from my Jasper Jig / router gouged the surface of the outer trim piece, so I had to use the back side (did not happen on the other two panels). The Jasper Jig did not go out to 18 1/2" with a 1/4" cutting bit, so I drilled a hole in the jig where one for 18 1/2" would have been. I sealed all inner edges with silicon caulk and used a ton of Titebond original glue.

I added egg crate foam to the front half of the box to reduce internal reflections (seems to have worked as the box is clearly less boomey when I stuck my head in the box and made noises. I am concerned about pieces coming loose and getting in the driver. Thinking about removing and replacing with two Wal Mart pillows so I don't worry.

**Mike P.** · **05-25-09, 09:09 PM**

Looking forward to the finished product. What will you power the Maelstom-X with?

**Navydoc** · **05-26-09, 04:44 PM**

I was thinking about the Crest Audio CC-2800, but have recently found some really good deals on the Crown XLS-802D (especially w/ the $100 rebate from Crown). This series is not rated bridged at 4 ohms, but according to a Crown engineer on the Crown forum:

"Crown doesn’t publish a spec for the XLSseries in Bridge-Mono because of regulatory reasons.
In the case of the XLS they will drive a 4-ohm Bridge-Mono/2-ohm stereo load but the XLS802 could under some peak conditions exceed 15-amps on 120v AC lines under testing performed by the independent testing labs. If the amp was being run hard with a 4-ohm BM load it could just exceed 15 amps of current draw, at full output, and would require it to have a 20 amp cord and plug.

It was a decided to drop the 4-Ohms Bridge-Mono/2-Ohms Stereo for all 120v units and keep the 15 amp rating for the XLS product line in the US. This way the whole line is consistent in their AC requirement scheme."

Based a web search the unit should put 2,100 watts into 4 ohms (bridged). For my needs this should be enough power.

**Ricci** · **05-26-09, 05:46 PM**

Hey did you get the XLS-802D already?

**Navydoc** · **05-26-09, 06:39 PM**

Not yet, the rebate runs until the end of June. Is there a better option at less than $350?

**tcarcio** · **05-26-09, 08:33 PM**

The Behringer EP-2500 is the choice of many here on the forum for their subs. It works great and has plenty of power. Check it out here...http://www.google.com/aclk?sa=l&ai=C...00_EP%25202500

**Ricci** · **05-27-09, 11:05 AM**

I'd pick the EP2500 over the 802D. If that's the budget it's hard to go wrong with the EP2500/4000 short of finding a killer deal on something else somewhere.

**Navydoc** · **05-27-09, 06:16 PM**

Ricci,

I really want to get a Crest CC-2800 or CC-4000, but the cost is a bit high. I should probably go with the EP2500 since it is available for less than $300. The XLS802 seemed like a good compromise since the quality should have been a bit higher than the EP2500 but not as good as the Crest products (or so I thought). The CC-1800 can be found on-line for less than $500, but doesn't have the power of the EP2500. Looks wise I MUCH prefer the Crest line.

I know there are a lot of fans of the EP2500 on the boards, but many others are not (probably that way with every single product if one were to look).

I am also leaning towards the ED eQ.2 for its two bands pf parametric equalization. For the price of a SMS-1 I could almost add a second MAL-X sub/EP2500. I will have to use my test tones and Radio Shack SPL meter.

Decisions, decisions, decisions!

Thanks to all for feedback and advice.

**Navydoc** · **05-27-09, 09:39 PM**

Quote:

Navydoc wrote:

I added egg crate foam to the front half of the box to reduce internal reflections (seems to have worked as the box is clearly less boomey when I stuck my head in the box and made noises. I am concerned about pieces coming loose and getting in the driver. Thinking about removing and replacing with two Wal Mart pillows so I don't worry.

Any thoughts on going with the egg crate foam?

I pieced foam to cover the entire front half of the enclosure (including the back of the front panel). I have spray adhesive to glue the foam to the box, yet I am concerned about a piece, or pieces, coming loose and creating problems.

After all the bracing I added to the enclosure I have calculated its interior volume as 5.8 cu ft.

Thanks again for all the assistance.

**mdrake** · **05-28-09, 01:02 AM**

I tested the Crown Against the Mackie which almost the same amp as the EP2500 and the Mackie got it's butt KICKED bad!!!!! GO WITH THE CROWN!!!!!! The difference between the amps was NIGHT and DAY! The Crown had so much more control over the woofer and the sound was tighter and much more accurate. I almost bought the EP but I am glad I didn't.

Like the saying goes you get what you pay for. Just my two cents worth.

Matt

**Navydoc** · **05-28-09, 09:17 PM**

Quote:

mdrake wrote:

I tested the Crown Against the Mackie which almost the same amp as the EP2500 and the Mackie got it's butt KICKED bad!!!!! GO WITH THE CROWN!!!!!! The difference between the amps was NIGHT and DAY! The Crown had so much more control over the woofer and the sound was tighter and much more accurate. I almost bought the EP but I am glad I didn't.

Like the saying goes you get what you pay for. Just my two cents worth.

Matt

Matt,

Thanks for the input. I never thought deciding on the amp would be the hardest part of this DIY project.

I had considered a Mackie, but I have seen to many negative comments on the boards. The XLS 802D seems good on paper, but I don't know how to evaluate (going to Guitar Center is an option - but I can't think of what sub they would have there that would be remotely similar to the Maelstrom since most pro subs stop around 30 Hz).

**mdrake** · **05-28-09, 10:22 PM**

Buying the amp was the hardest part me for me!! I went to guitar center and I explained what I was building to the sells manager at guitar and he was nice enough to let me take all 3 amps and bring back the two I did not want. I tested two Crowns and Mackie on my Mal-x, they did not have the EP in stock but according to what I have read the Mackie and the EP are very similar amps. I love my Crown but people seems to swear by the EP.

Matt

**Navydoc** · **05-31-09, 12:44 PM**

Matt,

I see you have Magnepan speakers. I am planning on modifying my MMGs for my next project and use with this MAL-X sub. How does your MAL-X sub sound with your Maggies?

**Navydoc** · **05-31-09, 08:19 PM**

Received more materials for the sub.
Madisound: 12 gauge speaker wire and Socket Head Screws (#8 x 1" Black Ox & Wax)
PE: Dayton BPP-G Premium Binding Post Pair Gold and Dayton SBPP-BK Binding Post Plate Black Anodized
Blue Jeans Cable: 25' Belden 1800F XLR Male/RCA Male (pin 2 hot, pins 1 & 3 bridged)

Sanded the entire enclosure and started gluing the oak trim pieces/legs.

**mdrake** · **05-31-09, 11:24 PM**

Well, the maggies are a sore subject. We tested them and they rolled of at 200hz, so I fell like I was lied to by Magnepan. Your MMG's should work good with the mal-x as they should be good to at least 80hz.

Matt

**random username** · **06-03-09, 10:46 PM**

a couple thoughts to pass on, I hesitate to speak for Kevin but I believe he recommended one pound per cubic foot on the stuffing, which ends up being pretty full. I used WalMart poly stuffing (not pillows). No concern on this sucking into the works of the driver as long as you don't pack it TOO dense. Historically when I've built subs I have just lined the walls like you did, not filled with stuffing so it was a "first" for me to do it that way.

In my opinion you would be better off with a BFD than a two channel EQ. Much more flexible. And knobs are nice for finding the setting you like, but once you find that magic setting there's no way to save it or prevent it from being inadvertently disturbed. The BFD will let you save several sets of settings, each with many parametric boosts or cuts.

Depending on your receiver or source's output, you may also need a signal boost, keep in mind you won't get it from either the BFD or the ED unit, that has to come from another unit (more info elsewhere on this forum,try a search).

**Navydoc** · **06-04-09, 09:02 PM**

Quote:

mdrake wrote:

Well, the maggies are a sore subject. We tested them and they rolled of at 200hz, so I fell like I was lied to by Magnepan. Your MMG's should work good with the mal-x as they should be good to at least 80hz.

Matt

Sorry to hear about the rolled-off performance of the Maggies. I was thinking about adding my MMG's as the side-surround speakers (mated with older Paradigm speakers). I know the timbre won't be matchedm but for side-surround I just don't figure it is that important. If I'm wrong, they will be replaced.

**Navydoc** · **06-04-09, 09:09 PM**

Quote:

random username wrote:

a couple thoughts to pass on, I hesitate to speak for Kevin but I believe he recommended one pound per cubic foot on the stuffing, which ends up being pretty full. I used WalMart poly stuffing (not pillows). No concern on this sucking into the works of the driver as long as you don't pack it TOO dense. Historically when I've built subs I have just lined the walls like you did, not filled with stuffing so it was a "first" for me to do it that way.

In my opinion you would be better off with a BFD than a two channel EQ. Much more flexible. And knobs are nice for finding the setting you like, but once you find that magic setting there's no way to save it or prevent it from being inadvertently disturbed. The BFD will let you save several sets of settings, each with many parametric boosts or cuts.

Depending on your receiver or source's output, you may also need a signal boost, keep in mind you won't get it from either the BFD or the ED unit, that has to come from another unit (more info elsewhere on this forum,try a search).

Random Username (perhaps the best username on the web),

Thanks for the advice, I am leaning towards the poly stuffing over the egg crate. One of my co-workers reminded me that the egg crate material tends to dry out and crumble. Not a good thing inside of a sub cabinet.

I will look into the BFD as a future upgrade, my wife is reaching the end of her tolerance for the project (wood, router, circular saw, power sander, router bits, clamps, etc). I have probably dropped almost $500 on tools - although they will be useful for future projects they were not in my cost estimate presented to the comptroller.

Thanks again.

**Navydoc** · **06-07-09, 02:38 PM**

Finally finished exterior construction. Added oak trim pieces to mimic my mission style furniture. Will try to stain to match. Used a 1.5" x 1.5" solid oak block to reinforce the leg corners. Unit is very solid and does not move.

Have a 3/4" lip around the top of the box (result of adding trim pieces to make the front of the box a square for adding a custom grill from Reliable Hardware [Round Perforated 16 ga. Steel; 5/32'' Diameter Holes; 32.63 Holes per Square Inch; 62.4% Open Area; Semi-gloss Black Powder Coat Finish]). Planning on adding a 24" x 24" piece (or 4 12" x 12" pieces) of slate or granite tile to the top.

**Navydoc** · **06-30-09, 08:08 PM**

Just got off the phone from placing my Maelstrom-X order.

Finished the cabinet with two coats of red oak stain, 5 coats of varnish and 2 rounds of wax. Looks very nice and I will post some more build photos when the driver is installed.

**vili** · **07-01-09, 08:29 AM**

Awesome, you won't be unhappy. I got my maelstrom in on Monday. It's been rocking the house so far.

**Navydoc** · **07-10-09, 08:13 PM**

Quote:

vili wrote:

Awesome, you won't be unhappy. I got my maelstrom in on Monday. It's been rocking the house so far.

Got my maelstrom this week, shocking how BIG and heavy it is - looking at pictures on the internet do not do it justice. The Socket Head Screws (#8 x 1" Black Ox & Wax) seem a tad small to hold this monster, but I could always go up to #10 screws or add hurricane nuts later if warranted. Should get it assembled tomorrow and start playing.

**nab9524** · **07-11-09, 10:48 AM**

I have been following your build thread, as I will be building a similar enclosure. I too have a Gen II Mal-x that I received this week, I agree that pictures don't do it justice, it is very big and heavy. How did you attached the external trim pieces and the legs to the box? I didn't know if glue alone would support the weight, so was thinking of putting some screws in from the inside.

**Navydoc** · **07-11-09, 09:43 PM**

Quote:

nab9524 wrote:

How did you attached the external trim pieces and the legs to the box? I didn't know if glue alone would support the weight, so was thinking of putting some screws in from the inside.

I only used glue, but I really painted it on both gluing surfaces and clamped overnight. I placed 1.5" x 1.5" solid oak feet on the bottom of the sub to help support the weight. Overall, I have over 100 screw holding the box together. I bought 16 1/4"x2" black lag bolts to give extra support to the external trim pieces, but after drying it seemed sturdy so I did not use them.

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