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  Topic Review (Newest First)
01-28-17 12:01 PM
Re: Sealed TC Sounds LMS Ultra 5400 18" NOOB STYLE!!

My box was designed to enable me to build and complete an enclosure as quickly as possible. (1 weekend)
The box size was calculated using WinISD for optimum bass extension and best distortion profile.
I wasn't concerned with the ultimate in strength or finish.
The box DID have to be (air tight) and substantial enough to easily hold the 85 pound driver.
I used 3/4 inch MDF single sheet on every panel and face.
Box reinforcement was done with 1x2 inch furring battens at every intersection of every panel.
Additional 1x2 reinforcement was placed at mid-panel of all panels to push nodal vibrations/resonances above 200Hz.
I enlarged bolt holes on driver rim to accept larger 1/4 inch bolts.
I used glue/screw/clamps/clamping straps to assemble box and 1x2 reinforcement battens.

I bought the 4x8 MDF from Home Depot and had them make the original panel cuts.
I did additional edge refinement using a Freud thin kerf ultimate fine tooth blade on a 71/2 Milwaukee circular saw.
I did all panel work on the floor using 2x4s placed under the panels for saw blade and router clearance.
I cut the driver and speaker wire binding post holes with a Freud router using a Jasper Circle Guide.
I used 1 3/4" wood screws and Elmers carpenters glue and clamps during glue dry/cure 24 hrs.
All Seams were carefully sealed from the inside with silicone caulking gun. The box IS tight.
Speaker caulk was used to seal driver to front panel rather than the included driver gasket. (gasket was oversized and didn't fit well under the compression of the mounting bolts).
I placed 2 inch thick sound absorbent polyester on all inside panels to reduce internal reflections.
I used #14 speaker wire to hook both voice coils in series and to hook speaker to binding posts.
Box and driver together weigh 120lbs.

Driver and box have performed excellently over time.
I have used this system at several GTGs. Always impresses.
On my thick pile carpet, the box never moves. I use a dolly to move it.
When energized with a couple thousand watts of power, the panels can be felt moving slightly at certain frequencies.
At normal listening levels there is no discernable panel movement, vibration, or audible discoloration.
I have two amps for the sub, Crown Xti 4000 and a Peavey IPR 3000/Behringer Ultra Curve Pro DEQ2496.
I prefer the Crown which allows hookup and analysis through a laptop computer for unlimited frequency curve adjustments
I cross the sub over @ 80Hz for normal listening with my home designed mains. I use no subsonic filter.
The sub reaches 10Hz and at that Fq will vibrate walls, doors, windows, and concrete floor when driven hard.
I have never bottomed the driver cone but have put the Crown amp into protection. The Peavey amp just goes into distortion.
The energy transfer from the titanium cone and huge magnet motor is astonishing. A visiting grand
kid accidentally put his small chair up against the cone surround and sat in the chair while a movie was playing.
When the sound track hit an explosion, the cone hit the chair and knocked the kid on the floor. It's possible he jumped from fright.

A room curve is really a necessity to get the best from this sub system. I have used this as a single sub without correction and the room modes are really bothersome.
With a good room curve reducing the response irregularities, the excellent low levels of distortion properties of this LMS driver become VERY obvious.
Music is astonishingly realistic, video games and movies become a life threatening reality.
The Crown amp DEQ provides ample room curve adjustments and can boost response to 10Hz.
The Peavey amp has no DEQ. You need the additional Peavey ultra curve unit to provide Fq adjustments. The Peavey amp and Ultra curve provide equal quality room correction.

For a choice of the most recent amps I would consider:
Behringer iNUKE NU12000DSP
Peavey IPR2 7500 DSP
Crown XTi 6002
Crown Itech 12000HD
01-27-17 09:22 PM
Blu Probably the best diy sub info out there.

If you could summaries the project and problems

I am interested in doing this. Not sure if I'll have time or patience.

If you could list the parts you used and why.

Thanks for your time
07-03-16 11:50 PM
Re: Sealed TC Sounds LMS Ultra 5400 18" NOOB STYLE!!

I added some pictures and details about the Dual RCF 21s on the above thread.
I hadn't looked at that stuff for over three years.
The pictures make it look so simple. It wasn't.
I think the neatest part of that project is that I used only 1 piece of 4x8 Birch Plywood . . . plus 20 feet of bracing.

The thread for my LMS 5400 build is here"
04-06-16 07:42 PM
Re: Sealed TC Sounds LMS Ultra 5400 18" NOOB STYLE!!

I was bored, here is a video of it in operation 4 years later lol. the mic on my phone makes it sound weird. Its a hard hitting sub
03-18-16 06:10 PM
Re: Sealed TC Sounds LMS Ultra 5400 18" NOOB STYLE!!

Wow, to post a build . . . . I dunno . . . . I'm moved into another computer and an additional 2 terabyte external hardrive. I don't recall if I sent that build with pictures to drive E or what. I'll take a look. That's 4 years ago at least. That build was for the 2 21s and not the 5400. I was really proud to be able to stuff 2 21s into a 9 cu ft box made from one sheet of 4x8 plywood. Nobody at the time seemed very interested so I never posted it.
That'd be like opening up an old war wound. I'm still pickin glue outta my hair and off my fingers from that one.
We shall see.
03-18-16 05:41 PM
Re: Sealed TC Sounds LMS Ultra 5400 18" NOOB STYLE!!

HAHAHA, that's awesome. My wife says that the subwoofer gives her a head ache and she cant really tell much of a difference on the surround sound other than there are occasional noises in the background. WOMEN!!!!!!! Me and her do not share the love of high end audio.

Did you do a thread when you built the latest LMS box? If so can you add the link. If I redo the box I will start a new thread and do it in overly done detail like I did this one.
It may be a bit if I attempt to rebuild it. The box is good, but just thinking I might want to try a new design for fun.

I just finished the designs and cut sheet for the Box going in my truck. Took a lot of measuring and re-measuring to get the angles for the box to fit under the back seat of my F-150, then a ton of searching to find the right sub for the space. was going to post the build on this site, but noticed there was no forums for Car audio.

Glad to see your still on here, send me the link or add them here. I want to read through your build
03-18-16 04:44 PM
Re: Sealed TC Sounds LMS Ultra 5400 18" NOOB STYLE!!

If you make another enclosure for the 5400 let us know how it turns out.
I'm still using my 5400 and the 2 21inch RCF NEOs for the bottom end.
I'm now using the XTi 4000 bridged for the 5400 and a Peavy IPR 3000 driven by a Behringer Ultra Curve Pro for the RCF 21s.
I'm so spoiled by the sound quality and power of the lower end that when I listen to other systems for any length of time,
I get pissed off.
My wife decided to buy a system to go along with her new HD 32 flat screen TV. She bought a JBL sound bar and the matching subwoofer to go along with it.
I was in the store when she bought it. She made me listen to ALL the sound bars and subwoofer setups Best Buy had, about 10 of em. I'll admit the JBL sounded the best of all of them even though the sub only had a 6.5 inch woofer. My wife thought she had the equal to my stuff down in the theater room.
N O T !
It turns out that although the JBL sub puts out BASS, it's all one note and THAT gets really aggravating after about 20 minutes. Who wants to listen to a
70 HZ note all night long whether it's for a man's voice, a roaring inferno, or the pods emerging in "War of the Worlds".
All you guys know what I'm talking about.
All those days of experiments we made and all those different brands of sub drivers and a thousand different box builds and determining how much amp power was needed to satiate our hunger for loud, literal gut wrenching, pants flapping, wall moving, earth shaking subwoofer power, finally paid off . . . . and I am at ease with the world, MY world . . . . where 10HZ on down is the norm . . . . . where 100dbs @ 20HZ is required . . . . . and the meek may not enter . . . . and our hearing won't last past 5 years.
03-18-16 02:48 PM
Re: Sealed TC Sounds LMS Ultra 5400 18" NOOB STYLE!!

Crazy its been 2 years since that last update. Still running strong and hasn't budged from its spot. I've been Gearing up to completely redo my truck. Receiver, all speakers, and adding sub, strictly sound quality, nothing to hear from blocks away. Since my first post here, I started working as an engineer and my main tool is Solidworks 3d modeling. Man does it make designing enclosures a whole lot easier. I'm debating on redoing this LMS-5400 enclosure. Ill be able to get it down perfectly with this software.
01-28-14 06:57 PM
Re: Sealed TC Sounds LMS Ultra 5400 18" NOOB STYLE!!

brandon123 wrote: View Post
I started this build on 4/30/2012 its now 1/27/2014. Still have the same setup and it has never moved from its spot next to the TV. This build was WELL worth the time, effort, money. I honestly believe the sub sounds better now, almost 2 years later, than when I first built it. when someone new comes over to watch a movie, its always ... ""WOW!!!""...or..."that sounds awesome" Thanks again Shack for all your help, couldn't have done it without ya
LOL good to hear it hasn't moved and is still operational.
I recently lent my LMS out for a GTG. Packing, carrying, and transporting the 6 cu ft. box with the LMS mounted inside was an interesting challenge. I decided having the driver positioned facing up was safest way to move it. Moving the box with the driver on it's side with the driver hanging from the mounting bolts would put too much stress on the MDF at the bolt locations. If the transport vehicle hit a RR crossing or pothole I was worried the driver would get torn out of it's mounting. I used nylon straps with ratchet clamps to tighten the straps around the box. I had two straps running under the box fastened to a heavier strap running parallel to the ground about 10 inches from the top of the box. This arrangement allowed two men to lift by the parallel strap lifting against the straps that went under the box.
Anyway the box and driver arrived safely and was fully functional when set up.
This is the first time I've heard my unit played outside my house in a different environment. My laptop which controls the amp's EQ was down so the unit played with my house curve logged in the amp.
It did well. The GTG members wanted the Crown amp hooked up bridged for 3200 watts. I usually ran it with one channel @ 1200 watts.
The unit filled that open listening area with more low end than anything else being displayed in the house. I had my demo test disc that had single frequencies from 10Hz to 100Hz spaced at 10Hz steps. The cone JUMPS with 3200 watts at the 10HZ setting. It looks like full extension to me. Had to be close to the bottom. The dubstep demo disc was vibrating the concrete floor of the living room and the various pieces of furniture. One of the owners lamps traveled across the end table and tilted against the wall without breaking. The house had not been LMS prepared.
The LMS was paired with two electrostatic speakers. The cross-over point needed to be changed from 80Hz to 120Hz for best integration with the electrostatics. After the loud demo stuff was over and the more detail specific material was offered, the SQ of the LMS was very evident playing with the electrostatics.
Only problem that resulted was that most members at the GTG now want an LMS.
My LMS is about 6 years old and hasn't had a problem. The LMS will suck up all the juice in an XTi 4000. It's a good match bridged. I don't need that much volume. I get by using one channel for the LMS and the other channel for dual RCF 21's in a 9 cu ft. sealed enclosure.
Good luck Brandon. Thanks for all the fun.
01-28-14 05:37 PM
Re: Sealed TC Sounds LMS Ultra 5400 18" NOOB STYLE!!

That's awesome - I'm very happy with my Ultras too. There are very, very nice subs for sure.
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