The Beast and it's Lair

[annunaki]

EDIT: Please see latter pages as this has now been adapted for use in my home.


Hey all!

I just got my subwoofer enclosure (for my car) finished last week and thought I would share it with every one. It has a net internal volume after woofer and bracing displacement of 2.17 ft^3 yielding a final Qtc of .713. I will be running it with 1000 watts of continuous power. It will be handling frequencies from 50hz or 60hz and down. The woofer is the JL Audio 12W7-3.

Here is the beginnings of the enclosure:

Here is the rear portion of the bracing installed inthe enclosure:

Here is the center section bracing and front baffle bracing before it is installed:

Here is the center bracing and front baffle bracing installed:

Here is the enclosure all buttoned up:

Here is the enclosure after the whole exterior was covered in fiberglass resin to resist moisture:

Here is the enclosure after a treatment of carpet (with the beast trying to get in! ):

Here is the Beast itself:

Here is the beast in it's Lair:

I will let everyone know how it sounds after I get everything else installed sometime this week. I did some very limited (time and wattage) initial listening and so far it is great, very detailed and transparent.

 

[j_garcia]

Nice My first speaker project was a car sub too. I had a 1.5" thick front baffle and 2 10" drivers in a sealed enclosure fed by a bridged amp pushing 400w. MAN did that thing hit hard. I sort of grew out of that though.

 

[annunaki]

This definitely not my first speaker project . 1.5" baffles are overrated. With proper bracing a .75" works great.

 

[j_garcia]

(not suggesting this was your first project )So was that 3/4 or 1" you used? I just used two 3/4" sheets to make up the 1 1/2" front, the rest was 3/4 and only one small brace in the center. I had a shop do a nice hidden install of the amp for it and when he hooked it up, he asked who built the box? "I did" . He said "It's ugly, but it sounds pretty darn good."

 

[annunaki]

Everything in the enclosure is 3/4" Mdf. I predrilled and countersunk all the screws. I used Elmer's wood glue on all the joints.

Enclosures do not have to look pretty to sound good. The construction quality is what matters most.

 

[Francious70]

Yes, it is a box.


Pretty good lookin. Not to many people even take the time to brace the inside of the box anymore, so I commend you for that. What's the rest of your system consist of??

 

[mulester7]

.....VERY nice, Annunaki....beautiful internal bracing/tuning pieces.....

 

[Buckeyefan 1]

Very nice work. The surround matches the felt perfectly in the photo. How do JL subs mount? There's no visible lip.

What vehicle is it going in? Rear facing? And what 1000 watt amp? A JL?

We finished an enclosure to fit under the rear seat of my F150 extended cab pick up. What a chore! But it was well worth the time. We also used 3/4" mdf in a divided, sealed enclosure with dual 10's. I smile every time I turn it up.

Out of curiosity, what does the box weigh by itself? How about with the driver? Lord knows I couldn't lift that mammoth.

 

[jaxvon]

Buck, here's a pdf on how to mount a JL sub. It's pretty cool and unique.

http://mobile.jlaudio.com/pdfs/W7_MountingSystem.pdf

 

[Sheep]

ah yes, the old fold back the surround and screw the driver, I remember reading that a long time ago.

That is a very nice box you have there, how much does it weight?

PS- I want to see pics of the beast in operation!

Sheepstar

 

[annunaki]

The system will consist of the following:

An Alpine CDA-7949 feeding two Alpine PRA-H400 Digital Crossovers w/time correction via fiber optic cable. The two processors/crossovers will then run three amplifiers. One JL Audio 300/4 which will feed 75 watts continuous to each tweeter and midrange. One JL Audio 300/2 will feed two mid bass drivers 150 watts continuous. The JL Audio 1000/1 will run the JL Audio 12W-7. The Front stage speakers are the Alpine SPX-F17T three way components. They are actually High end Vifa derivatives. The system will be fully active in terms of crossover. Each speaker will have it's own amplifier channel and digitally crossed over channel (high pass at 18db/oct. low pass at 24db/oct.)

My vehicle is a 2000 Pontiac Grand Prix GT. The sub will fire into the car through the fold out in the rear seat. The subwoofer will be sealed off from the rest of the trunk to avoid cancellation. Additional venting to the cabin, when the seat opening is up, will be through the rear speaker holes. I do not run rear speakers as they detract from the front stage.

I did not actually weigh the enclosure. I do not have a scale at work. However, as a guess, with the sub (the sub weighs 45 lbs) I would say it is about 90-100 lbs. It is a pig.

Sheep, I will see what I can do about some pics once everything is done. It has a totally linear, 2-way excursion of 2.5"!!

 

[Sheep]

Thanks for the response, remember, slow the shutter speed to get those cool ghosting looks

Sheep

 

[annunaki]

Sheep,

Hopefully my cheap digital camera will do the job. Would exposure compensation be similar to shutter speed??

 

[Sheep]

Sheep,

Hopefully my cheap digital camera will do the job. Would exposure compensation be similar to shutter speed??

To be fully honest with you, I have no clue. I heard that slowing down the shutter speed was the way to get that effect. Give it a try, you can always delete it if you doesn't work out.


Sheepstar
EDIT: post #600

 

[ironlung]

Nice Box!

Sheep,

Hopefully my cheap digital camera will do the job. Would exposure compensation be similar to shutter speed??

Nice work on the enclosure! Very crafty.

Yes sir, looooong exposure time will give that look of movement. Watch out for bright light to avoid being over exposed (washed out) and use a stand/tripod and the timer if possible to eliminate trembling hands. It should be a cool looking picture with 2.5 inch excursion.

You could probably figure out a good shutter speed for a given Hz output to only catch a few pumps of the driver. I'm to lazy.


Good Luck,
Ironlung

 

[Francious70]

Any particular reason you decided to run an all JL and Alpine system?? Just out of curosity.

 

[Sheep]

Any particular reason you decided to run an all JL and Alpine system?? Just out of curosity.

Simple. JL and Alpine are some of the best sounding car speakers out there. I perfer them over ANYTHING.....but I'm not a doctor.....



SheepStar
PS-Where's them pics?

 

[annunaki]

Sheep,

The camera sucks I cannot get it to do the trick.

Francious,

I did Alpine and JL for some of the following reasons.

I did the CDA-7949 because it was the best sounding deck I have ever had. It is reliable. It has a great user interface. It has a fiber-optic output. It has full Ai-net control. It has a copper plated chasis.

I did the PRA-H400s because they were the only high quality digital crossovers I could find with digital time correction and fiber-optic input. They also use dual 18 bit DACs on all channels. That and they link up perfectly with the head unit.

I did the Alpine SPX F17T three way speakers as they were one of the better designed systems available. The drivers are all Vifa/Scanspeak derivatives. I also got a killer deal on them.

I did the JL 12W7 because it is the best raw driver I have heard save the W6v2, bar none. That and it offers the same output of 2-3 decent subs.

I did the JL amplifiers as they are some of the best designed amplifiers available. Bruce MacMillan (sp?) designed them, think PPI Art Series and Power class, Xtant (original not Mitek). The JL amps are a culmination of all of the stuff he was designing at the other two companies.

So far the system sounds very good. I do not have my custom kick panels made yet so I am without the mid-bass drivers. None the less, I am quite happy with it so far. Clean, accurate and dynamic. The system sounds effortless even at high volume.

 

[Tdekany]

Any reason for not going with the 13W7?

 

[Francious70]

Have you heard the Image Dynamic's IDMax?? I'd say it's comparable if not better sounding than the W7, half the price, and offers just as much output.

http://www.imagedynamicsusa.com

And about the amps, if we all agree that a properly designed amp will sound the same as another properly designed amp, you could've saved yourself a large chunk of change, and gotten more power to boot, if you went with Phoenix Gold Xenon 1200.1, 200.2, & 100.4. Not to mention that the Xenon's are more efficient than the JL series.

But, that's just my $.02 I'm a fan of saving money on products that offer the same performance of overpriced products. *cough*MONSTERCABLE*cough*

I'll have to post up picks of my car system some day.