tc sounds lms-4000 enclosure critique

**ringbearer3791** · **06-27-08, 06:37 AM**

I've actually managed to get a little bit of work done this week and I'm hoping to get some more done tonight. I'll try to get some pictures up in the next day or so.

As far as finishing it, I'm planning on veneering it and then trimming out the deck and corners with hardwood, probably mahogany. I haven't settled on what veneer I'm going to use yet, but probably something in the line of figured or brazilian cherry.

Thanks for the interest, I'll do my best to get some pictures up quickly.

**ringbearer3791** · **07-01-08, 07:18 PM**

ok, slight delay in getting the pix up but here's a few.

**ringbearer3791** · **07-01-08, 07:22 PM**

so, the bracing is in and sealed, and very ugly as you can tell. the local hardware store recommended something called lexel as the sealing caulk. it's more or less the consistency of rubber cement but I have to admit, as ugly as it is it's pretty effective. then internal cap is ready to get installed, all that's left is to cut the port braces to length and install them. hopefully that will happen this week and I can start worrying about screwing up the veneering.

Josh

**Blaser** · **07-03-08, 03:41 AM**

Josh,

It's not that ugly.... Nice work!

**eyekode** · **07-03-08, 06:47 AM**

I don't know if it matters (and I am of the opinion it doesn't) but many people round over the cutouts on the internal bracing.

Oh, and it looks fine to me. The hard part is getting great corners/edges. You either do it with great cuts and flush-trim router bit or with bondo

**ringbearer3791** · **07-03-08, 06:57 AM**

Thanks guys. Yeah, getting good corners has definitely been a greater part of the work. lots of careful measurement followed up with an orbital sander when either I or the table saw fails to get the pieces perfect. I'm getting some foam lining for the sides today so I should have some more pictures available over the holiday once I get it installed and button up the remaining pieces.

**ringbearer3791** · **07-14-08, 07:03 AM**

Success! (maybe) Sorry for the hiatus since the last post and unfortunately I still haven't gotten around to uploading the pix from my camera to the computer so I don't have any to post today, maybe tonight when I get home. Everything seems to have come together well, and surprisingly well fitting. At this point I'm planning on taking this thing upstairs into the family room to run it for a bit and make sure that it sounds right before spending the time and money on veneer. That said I still need to pick up an ep2500. Does anyone know the best (cheapest) place to pick one up? I seem to recall a couple of suggestions from people in other threads but I'm having trouble finding them. Thanks.

Josh

**Mike P.** · **07-14-08, 11:30 AM**

It's available for $258 from the Shack store. If there's a cheaper price hopefully someone will post it.

http://www.hometheatershack.com/elec...Power_Amp.html

**ringbearer3791** · **07-15-08, 07:13 AM**

Ok, i've got a few pix of the (more or less) completed build. I neglected to get a picture of the insides after the foam padding went in, but we all know what egg crate foam looks like right?

The first pic shows the opening and rails for the vents to exit from the top of the box. The second shows the vents as they wrap around the edge and exit towards the floor. The third pic is of the completed box, just missing legs (and some cleanup work and seams!) and the final pic shows the underside of the box where the vents exit. This project has been tons of fun, now i just need to get the amp and plug this thing in! I'll be sure to let you all know how it sounds.

Josh

**ringbearer3791** · **07-28-08, 07:34 AM**

Just a quick update. The sub is up and running! I haven't had a chance to run a real calibration to get it optimized with the rest of the speakers but it already sounds great! It's not an SPL monster, but that wasn't the design goal anyway, but the sound is so clean and it digs so much lower than my old sub! I haven't veneered it yet as I wanted to make sure everything sounded right before I spent the money but as it stands I'll definitely be off to get the veneer soon. Thanks to everyone for the help and suggestions.

**thxgoon** · **07-30-08, 02:36 PM**

Glad you like the sound! It's too bad TC isn't around anymore...

**ringbearer3791** · **07-31-08, 06:32 AM**

Thanks. I don't have REW to be able to post a really thorough plot of the frequency response of the sub but I did download some of the test tones so I'll sit down with the trusty SPL meter and take some readings to be able to post something. Thanks to everyone here who's helped me out along the way. I'll also definitely post pix when I get this thing veneered and finished.

Josh

**ringbearer3791** · **08-04-08, 07:07 AM**

well, I finally sat down and took some measurements with the trusty SPL meter and some test tones. I downloaded the excel spreadsheet from the REW section to calibrate the readings from the SPL meter. As you can see in the picture below, I've got a large hump in the response right around 40 Hz and a dip at 25 Hz. The sub is crossed from the receiver at 80 Hz so I only ran tones up to 111 Hz as the majority of sound at that point was coming from other speakers anyways. For those of you with more experience, do the hump and dip look like room response or like the sub itself? The sub is next to the sofa and isn't corner loaded. Thanks.

**eyekode** · **08-04-08, 08:29 AM**

I am not sure about the 25hz but it looks like one dimension of you room is ~14feet?

All untreated rooms will have large nulls and peaks in them. There isn't much you can do about the nulls without actually treating the room with acoustic material (like large corner traps). The peaks you can eq out.

**ringbearer3791** · **08-04-08, 08:37 AM**

yeah, the room is roughly 15X21 with 8.5 ft ceilings. I figured these peaks and nulls were probably room-related, but from my readings I'd figured that any room-gain related peaks were likely to be below 40 Hz so I was a little surprised to see a peak that large at 40.

**eyekode** · **08-04-08, 09:26 AM**

This is not "room gain" per se. This has to do with your room modes. Most every non-eq'd room will have this peak around 40hz (I guess because 14" is a common room dimension

).

**ringbearer3791** · **08-04-08, 09:30 AM**

Great, that at least makes me feel better. I was a little concerned that I might have somehow really screwed up to have caused a peak like this.

**mgboy** · **08-06-08, 11:42 PM**

Quote:

eyekode wrote:

This is not "room gain" per se. This has to do with your room modes. Most every non-eq'd room will have this peak around 40hz (I guess because 14" is a common room dimension

).

14" makes a pretty small room. =P

**ringbearer3791** · **08-07-08, 10:00 AM**

A large dedicated home theater just isn't in the budget yet. Young, new baby, mortgage, etc etc etc. Someday I'll build a house with a dedicated theater, but for now 15X21 is what I've got and I'll do my best to make due!

I should mention, I just watched master and commander 2 nights ago for the first time in a long time. I pretty much spent the entire movie with a big s**t eating grin on my face listening to the battle scenes. Mission to get a lot more ultra-low frequency content has been accomplished!

**ringbearer3791** · **09-26-08, 01:03 PM**

just a quick update, it's been a while since I posted but since last i wrote i've pulled the sub out of the listening room to finish the asthetic treatments. I'm veneering it with some slightly figured cherry and trimming it out with mahogany. The veneering is done (I used the titebond/t-shirt/hot iron method and have to say it's pretty idiot-proof) and all of the mahogany has been routed and cut. I'll try to remember to snap a couple of in-progress shots tonight when i'm home to post. this little project has taken forever but seeing the light at the end of the tunnel is really motivating me to get a move on.

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