The Sunboxsub (SBS) - from the construction progress - It's done! (1 Viewer)

[Patrick Sun]

Here's a few shots of the construction process/progress. I don't have much time to go into detail right now, but maybe a picture is worth a thousand words...
Photo 1
Photo 2
Photo 3
Photo 4
Photo 5
Photo 6
Photo 7
All that remains is the glue/clamp/caulk portion, and putting on the legs and bottom plate.

 

[Patrick Sun]

Some more details of the project:

Driver used is an original SVS 12" driver used in their PC and CS subs before they offered the new upgraded versions of their 12" sub drivers.

The outside dimension is 18"x18"x40.5". The sides are single layer of MDF with bracing from 2x2's along the panel joints, and single layers of MDF inside the enclosure in both vertical and horizontal directions. The top and bottom are double layered MDF. There's a closed off section for the amp so it is isolated from the thumping inside the enclosure.

I've been debating on whether I need more horizontal braces (like every 6", or is 12" spacing enough)? Internal volume will hover around 4-4.5 ft^3 depending on how much more bracing I throw into the box. The flared port is a 4" Precision Port 19" long from end-to-end (I have leftover section from a previous project which is where I got the extra inch of tubing I needed (otherwise, the port kit gives you only 18" end-to-end for an effective port length of 17"), and is supposed to tune to around 20Hz.

Also, SVS only uses a 2" clearance for their bottom endcap and the base plate. I'm thinking of going with 3.5" of clearance. My base plate will be double layered MDF with the same 3/4" roundover on the edges of my top and bottom sides for its exposed side.

 

[Jeff Rosz]

nice work pat
sabre saw for the shelf braces? i bet yer still buzzin.
i think GM or TW told me once the rule of thumb for bracing was... no panel area larger than 1 ft^2.

 

[Patrick Sun]

Actually, I used a router to free hand the holes for the bracing. I hate using a saber/jigsaw.

 

[Patrick Sun]

No pix (they are still in the digicam), but here's an update anyway:

I have glued up all but the front panel. The inside edge bracing has been caulked/glued and installed inside the backside of the enclosure (for all possible edges. Once I glue up the front panel, I can finish off the rest of the bracing (it'll be a chore since I'll have to go through the port/driver hole openings to install the remaining braces with the final panel glued in place).

Once this is done, I will glue the outer top and bottom outside panels, and install the port, and driver. Then install the plate amp, the legs, and base plate.

I'm probably a couple nights away from being operational.

I did not quite grasp the enormity of the this 40" tall box until I put the box in its normal vertical orientation temporarily as I moved stuff around to get the clamps in position. Yowie! This is going to be a heavy sub.

 

[Patrick Sun]

Here's a quick shot of the in-progress enclosure:
Photo 8
I just have to do 6 main things to finish up the enclosure:
1. drill screw holes for the bottom panel for the legs.
2. glue the outer bottom panel to the rest of the enclosure.
3. drill screw holes into the legs/dowels
4. screw in the driver
5. screw the legs to the base plate and the bottom panel.
6. screw in the plate amp and the port

 

[ColinM]

What's up with that hammer?

Modified to give a greater swing in tight areas?

?

Nice work!

 

[Patrick Sun]

Uh, yeah, that's the ticket. Actually I have no idea where I got that hammer, or what it doesn't have a backside (nail-remover) to it).

 

[Nick_Shah]

How heavy do you anticipate this subwoofer to be? (once the driver and amp are in)

-Nick

 

[Patrick Sun]

Hernia-producing.

Maybe...100 pounds...

 

[Stacey_V]

Excellent work Pat, as usual! Please keep up with the progress pictures as I, and many others, really do enjoy them. I followed your Sunosub progress earlier, and that is what got me to take the plunge and create my own. I've been toying with the idea of making another sub...this may be the final push I need.
Nice sandles BTW!
Regards,
Stacey

 

[ClarkZ]

Is this sub designed to stand up (40" tall) or lay flat the way that it is in the picture?

 

[Patrick Sun]

Stacy, fear not, the rest of the photos will be published one of these days when I get some time to write the webpage for it. I'm almost done! I'm so glad I had socks on when I took that shot with the flip-flops in it.
Clark, the enclosure will stand 40.5" upright plus the base plate and the legs.

 

[Patrick Sun]

Okay, I've finally finished the SBS (sans cosmetics).
Photo 9
Slapping in the driver, amp, and port didn't take too long. It was all the other small details that took me a week working nights while also playing in a couple of softball games and eating out once this week that slowd me up a bit.
But I've got it hooked up and it's pounding away on Rush's Moving Pictures. At first it sounded strange, but then I adjusted the phase and the bass finally sounded normal to me. I haven't calibrated it (no need since it's not really mine, nor is it staying in my house/room) but going by ear, I went with 2/3 of the plate amp's power, and use the receiver's subout trim to lower it by 3dB. I set the plate amp's low pass around 90-100Hz (due to my receiver's LF cutoff when the sub's on). It sounds balanced now to me at the moment, though it's not in the best location in my room.

 

[Ron-P]

I'm am just glad I am not Pats neighbor
Very nice work Pat
Peace Out~

 

[Patrick Sun]

Well, I've re-tuned this sub to around 17Hz, and did the plate amp mod (rumble filter at 16Hz, no bass boost), trying to dts-Haunting-proof this sub, but it ain't happening. I basically have to turned down the plate amp's output level to get non-popping response from the most demanding bass passages otherwise so-so movie. The plate amp level is only 1/3 of the full dial turn (it points to the last "r" in "crossover" on the plate amp), and my sub level is -7dB or -6dB calibrated with Avia.

It does survive the Phantom Menace AC-3 LD on the pod race section quite well (peaks of 96dB at my seat with the RS SPL meter during the race was loud enough for me). It survived Toy Story 2's opening scene (around 0:50 seconds into the film), but there was one pop when the gang is in the ventilation ducts just before the 1 hour mark.

I'm going to test the dts Jurassic Park LD and U-571 tomorrow.

For normal films, the sub is doing well. And music is very tight, enough to impress me, even when I crank up the music.

 

[Cam S]

Nice looking sub there Pat, but man, your back is gonna hate you!

 

[ArmenK]

Pat, did you cut the boards yourself and if so what did you use?

 

[Patrick Sun]

Cam, yes, my back curses me daily ever since I built the SBS.

Armen, my friend has a pretty nice table saw setup at his house, so that's where I get all my MDF panels cut to spec. He's a real nitpicker when it comes to cutting the panels just right, so my project come out looking pretty good with his keen eye on detail for the cuts and getting the panels to fit just right.

 

[Patrick Sun]

I re-tuned the port for 18Hz (took out 4" of port length), and tested out the Pod Race, and it survived. Then I tested out U-571's dts track when the depth charges get dropped on the sub, and that was nice and bassy. I also tested my dts Jurassic Park LD (chapter 26 - where the dino is causing havoc with the humans - eats the lawyer) and it survived all the dino stomping and roaring.

I have the rumble filter Fc set to around 21Hz on the plate amp just to give it a little more protection down low, with just a hint of bass boost in the 31-35Hz range. I think I'll stick with this setup for now. Current plate amp mod: R26=39Kohms, R27=150Kohms.