Return of the custom audio build diary!

[alanw6]

Due to the server crash, I lost the thread I had started a few weeks ago documenting the steps of a custom audio buildup for my 92 LX hatch. A lot of good info was lost, so I'm going to start this over and recap what has been done as well as what is new.

Progress has been good over the last few days, with great weather this weekend getting me out to make some sawdust.

Here is the first steps of the project, a fiberglass tub in the tire well to serve as the lower portion of my enclosure for one JL Audio 12W6-V2. The volume (airspace) of this lower tub is 1.25 cubic feet. It was measured with water and converted from liters to cubic feet (39 liters roughly).

Masking the area with aluminum foil and tape:

Initial layup of chopped fiberglass mat:

Adding layers for strength (total of 4 layers when complete):

Final buildup of edges and seams:

Tire well tub removed, with my bengal Mia as my model:

Edges trimmed and tub in place for wood work to begin:

Any questions I'll happily answer, and I do know there are quite a few knowledgeable people who will kick in their thoughts (89sleeper, pimptout, etc).

Alan

 

[alanw6]

After this early fiberglass work was complete, it was time to build the amp rack and the upper portion of the sub box. I intend to raise the entire floor about 3 inches, and a trim panel will be put in place for a nice, clean layout.

Here's where the MDF started to fly!:

Thinking about the placement of the amps:

Top panel of tire well tub trimmed and opened up for access to attach to the fiberglass:

Top plate attached with more fiberglass (Evercoat Kitty Hair, long strand) and test fit again:

Amp rack assembled and upper chamber of box shown without the top baffle plate:

I'll start one more reply with some more pics that bring it to it's present state.

 

[alanw6]

OK, the amp rack and box are complete. The rear trim panel is next, and pics will follow. There will be a custom CNC milled speaker grill to accent the trim panel and make the design a little more visually interesting. The grill will be the "S" in my company's logo (in sig), and the "needles" of the logo will be flushed into the trim panel.

Testing sub for placement/centering (this one is for you pimptout!):

Equipment mocked up in the position they will be installed (sub won't be upside down, although it does look cool):

Another angle of the equipment test fitting before assembly and some finish sanding. A master woodworker, I am not! But I do try hard.

There's a little bit of work to do on the box and rack to prepare them for final mounting. I may need to tweak the volume of the box a little, as I want it perfect.

Got started on the lower door panels tonight, so some more fiberglass pics will come this week. Then it's time to strip the interior, wire it, replace the carpet with brand new mass-back ACC from 5.0 resto, and deal with the radio/HVAC/processor location. A few more custom bits will be incorporated, so keep an eye on this thread.

Hope this thread is as good as the other one was. I'm open to answer anything I can related to this type of project. My goal is to get more people to do something custom on their own, and help them realize it's very doable!

Alan

 

[Philstang]

Thanks for the update Alan. I was just about to request you put up a new thread until I saw this one. Looking good so far. At first I was curious what you were doing with that rectangular cutout but the latest pics answer that.

 

[9T3SVT]

It looks great so far, I need to have mine redone. I wanted to have the sub and amp lower but it ended up like this....

 

[shootme5150]

Looks great, man. What kind of airspace did you get out of the well alone, do you know? Oh, and what is your front stage going to consist of?

 

[alanw6]

9t3svt, looks good. Which ppi amp is that? A 6 channel or a big 2 channel for the sub?

Phil, I'm not surprised you wondered about the cutout. I needed both more volume than the well offered, plus more depth as that sub is pretty hefty as the pic shows. This is why I raised a chamber up a little to match the height of the amp rack. This will allow the trim panel over the whole thing to sit flat. This weekend looks nice, so I'll do it then as well as the door panels. I've already cut the frame for them to be built up from.

shootme5150, the airspace of the well alone was roughly 1.25 cubic feet without the upper chamber. I'm at 1.6 with the top chamber, sealed.

The equipment rundown is pretty cool (to me anyway). It's a lot of older gear that I spent 6 months searching out on ebay and elsewhere (in new or as-new condition). Only the speakers are brand new, but I feel the electronics from a few years ago are equal or better than what I can get now. Plus, it has sentimental value to me from my car audio days. It's the gear I could never afford as a college guy.

The system components:

Eclipse 5302 CD indash with 5 volt outputs and no internal amp
PPI FRX-322 half-DIN crossover
PPI PAR-245 half-DIN parametric equalizer
Phoenix Gold MS-275 for front stage
Phoenix Gold MS-275 or MPS-2240 for sub (I have both, depends on power class I'll run if I choose to compete, as they are the same chassis but rated diferently)
MB Quart PSC 216 2-way 6.5" separates with musicomp crossovers
JL Audio 12W6-V2 sub
JL Audio power/signal cable
Kimber speaker cable (unless my wallet faints)
Custom switch panel for system valet, fans, lighting in amp rack, and amp turn on (to defeat either amp for tuning purposes)

That's about it for now. I'll post more pics as they happen.

 

[alanw6]

Sorry for the double post, but here are few new pics of the door panel frames (1/4" birch plywood) before the fiberglass work begins again. Also, a snap shot of the finished rack and box without the equipment in place.

My new issue of MM&FF came in recently, and I see there is a two part writeup of an install. I'm really curious about how they are doing the tire well, as it seems they might not be using any glass. It looks like the back wall of the tire well in their car is glued to the floor! Can't wait to see the finish next month, as it will answer my questions I'm sure.

 

[Philstang]

yea, I have seen an install article where they did not use glass for the bottom. They just built wood sides and used the tire well surface as the bottom of the box and just sealed where the wood sides met with the floor. Definitely not a removable box!

 

[alanw6]

yea, I have seen an install article where they did not use glass for the bottom. They just built wood sides and used the tire well surface as the bottom of the box and just sealed where the wood sides met with the floor. Definitely not a removable box!

That's what I was thinking as I saw the article. I was like, "no they aren't - are they going to glue this wood to the CAR?" We'll see next month I guess.

I'm getting excited, as now it's starting to resemble something and so far I'm on track to making it look like I envisioned.

 

[joelliott]

Im back. I was just wondering about this thread today. Good to see its back for the final processes...... thanks.

 

[shootme5150]

If I can make a suggestion... expensive cables are truly a waste of money. Unless you have some deep seeded need for them, I'd recommend standard, generic cables. Wire is wire, it's nothing but a conductor... Things look great... I hope to be throwing something sick in mine later this year.

 

[alanw6]

If I can make a suggestion... expensive cables are truly a waste of money. Unless you have some deep seeded need for them, I'd recommend standard, generic cables. Wire is wire, it's nothing but a conductor... Things look great... I hope to be throwing something sick in mine later this year.

You know what, I agree with you. I agree with you almost 100%, but have a few reasons for my choices.

I deal with a lot of high end cables in my day job (custom home electronics) Overpriced? Oh hell yes. No doubt. Can I hear the difference? Probably not.

BUT, this install is the realization of a lot of my dreams/ideas and using nice cables is more a choice of aesthetics than performance. Lamp cord would, indeed, work just fine when it comes to electrical resistance and ohm's law. But, really nice cables just look better when connected to nice equipment as opposed to the regular stuff. I'm fortunate to have no real budget on this project (within reason), and the details are important to me.

My personal belief is that all wire is not created equal, but the rate of diminishing returns is steep after a point. The really wild cables are simply overpriced versus their effectiveness. I'd never use them, short of powerball coming through.

 

[Blakthorn]

nice work

 

[alanw6]

Got some good work done today, where I focused on doing the lower door panels for the front speakers. One of the posts above shows the cutout of the speaker/map pocket area I made from 1/4 birch. Here's what followed today:

I wrapped the panel cutouts in foil, and then secured them to my work surface with a 3/4 inch spacer underneath.

Then, I wrapped and stapled the mold fabric (a stretchly fleece material) to make my desired shape.

After making the same jig for the other side, they were both coated in fiberglass resin.

The panels were removed from the jigs and trimmed the excess fleece. The rough door panels are now ready for a little body work, which I'll do this week.

To make sure everything is still on track, I did a quick test fit to see how it would look in the car.

I'm pretty pleased with the outcome. It took about 5 hours to do, and the result was clean enough for the body work to be pretty easy.

More to follow soon. The really tough stuff is out of the way, but there is still the radio area and the rear trim panel to make.

 

[shootme5150]

Can I hear the difference? Probably not....
My personal belief is that all wire is not created equal, but the rate of diminishing returns is steep after a point. The really wild cables are simply overpriced versus their effectiveness.

From a physics and electrical standpoint, I can assure you they don't give you anything. I'm happy to hear you know the difference, though... and you have a reason for putting them in.

Those are great panels... I'm going to be trying to stuff some 8s in my doors sometime this year, hope they turn out that well. Are you running 3ways? It would be a shame to put that much time and effort into the setup and not use kicks.

 

[alanw6]

My plan is to do a 2-way setup, and I have a pretty good concept of mounting the tweeter which should provide a pretty good image. I will wire for a 3-way setup when the interior is removed, in case I change my mind. With the 5-speed, I'm not positive I wanted to lose the foot room.

This car won't be an audio competition vehicle, so sacrificing a little front stage quality won't bother me. I've done multiple foxes with both 2- and 3-way setups, and have had good results both ways.

Glad you understand about the wire choice being aesthetic more than anything. You are right though, the electrons won't know the difference!

Alan

 

[shootme5150]

2 or 3-way doesn't mean much... actually in theory 2-way is the better option solely due to wavelength variations and cancellation. Out of curiosity, when you built those panels, why didn't you angle the mids a tad, again for imaging and stage?

Big advantage for 3-ways, IMO, is the small mid and tweet don't take up much room in the well. I'm going to buy some Dynaudio 3-ways from my boy this month... sealed mid AND tweet means you don't have to make a true 'enclosure' in the well. That rules. I've got some CDTs right now that take up almost no room. I just don't think you can beat the stage of a set of well designed kicks.

 

[alanw6]

I debated angling the midbass rings for a while, and ultimately made the decision to keep them flat and parallel with the door panel.

I based the decision on the good off-axis response characteristics of the quart driver and felt a few degrees wouldn't affect much. Also, tilting the rings would have made the protusion much bigger, since there is little depth to create a good angle. The inner door skin is just right there, and I wasn't going to cut it. Had the doors/panels had some depth, I would have angled them slightly up and back, which has worked well in other cars I've had.

 

[Ozz]

Look great, Alan!!