Project LFE
Low Frequency Effects

Note: This is a SQ build- for anyone who throws away the T/S parameters b/c of too much mathematics- this build may not be for you...

Well this winter I'm staying busy with my Max. My projects are mainly indoors because of the cold wet weather. For a long while I've wanted a little extra bump in audio system and lately I really wasn't impressed by the majority of what's out there for auto enclosures. I have my eye on a few JL products but the cash is running low after the holidays. Most prefabbed I found boxes were huge and extremely heavy, built for comp 10's or 12's, while the smaller lighter ones were a joke and could only be mounted behind a truck cab seat. So, armed with the criteria of wanting a box to hold my 2 - 8's, room to mount an amp + a cap, and locate 1 speaker to play directly in the cab I set out to build a custom box for my 4th gen.

Before you guys gone on about this...
I have to field the main question: "Why all of this for 2 - 8's?"

* Primarily I'm going for SQ not SPL. I have 2 SilverFlute Wool Cone 8's to match the 2 6.5's in the front doors. The sound from a natural material, like a wool cone, is rich, full, and warm it must be heard to be believed. As apposed to thin, harsh, blatt... from your standard plastic "poly" propylene cones.

*Second I want to hear 20 years down the road. 2- 8's on 300 watts with one playing directly into the cab is plenty of mid bass to feel the music even on the highway with the windows down.

*Finlay weight is a big issue. Building a "rigid" box for 2-8's isn't a huge task. 7/16" board and some x-bracing and your done. However 2-comp 10's/12's require heavy 3/4" mdf AND x-bracing that make your trunk sag and your wallet sore. Since I like to travel to the Mts and keep good gas mileage in the city a small light weight box was the only way to go.

Back to the project

After taking some initial measurements






I set out to build a trapezoid style box...



It took a few tries with foam core prototypes before I actually cut the wood, but once I got it right I was very please with the results. The primary placement objective for the box was to utilize the space deep in the trunk and not interfere with opening the spare tire hatch.







Using some quick internal measurements of the complete box and the two box volume calculators on http://www.bcae1.com, I calculated ruffly 1.94 internal cubic feet while accounting out the internal brace area. (these are rough internal measurements- not 100% accurate for making a new box from)



Future plans:
My future plans include calculating a port size and tune it to my drivers. Apply the Vinyl Laminate Covering I picked up from parts express -PE)& finnaly connect my trusty amp and enjoy the music ...


I hope everyone is staying productive on their indoor projects this winter. Stay tuned for more updates to Project -LFE.

Side note
-For those of you who are going to ask- the capacitors hanging down in the measurement pictures are part of my Zobel line filter for the 6x9's I installed in the rear deck.

 

curious to see where this leads to...haven't seen a build thread in awhile.

what's your front stage setup?

 

nice budget build you got there are you planning to damp your trunk and door panels?

 

Thanks for sticking around guys

@jin4g63
I would like to damp the front doors and the rear seat, I get a lot of road noise but $$ is a factor why it hasn't happened.

@AscendantMax

Up front I have two 6.5's in the door (wool cone) and two .75" tweeters on the pilar. In the rear deck there are two eclipses 3-way 6x9's. Would like to update the rears with new component 6x9 however I haven't had the spare cash. Any suggestions on a budget 6x9 component would be nice .

Driving it all, is the eclipse CD-8455. For everyone in the know, it was/is the deal. If you don't know it has a 24-bit dsp, 8 volt pre-outs, and an in cabin mic for audio frequency leveling. It acts a little quraky at times, the display freezes and the volume **** will stop working every now and again but it's a good unit lots of active crossover features and I picked it up for $250.

The front stage is good but I would gain clarity if I dedicate mid bass woofers, from the 2 8's setup in the works , and raise the x over point for the front and rear drivers.

Pics from the 6.5's break in period last year. 36 hours of sign wave tones made the surrounds and spider butter and raised my Qms


comparison of the old eclipse 2-way 6.5 (right) and the current 6.5 in the front door (left)




this will show you how far the obsession really goes...

After spending a lot ot time rewiring the car with silver coated 12awg speaker cable and custom mounting the door 6.5's. I wanted to insure the HU received clean power to factor out any audio anomalies due to power. Concerned about AC ripple from the alternator & transient power spikes from the fans, lights, motors, and relays I researched a way to filter the battery power to the head unit's inputs. After a while of studing electrical books and reading a/v forums I discover a Pi filter would clean the power and isolate my audio system. Running a 6awg cable from the battery to it and then to the HU i can rest easy my HU is safe and feeding on clean dc power.

(in it's early design stage)


it is over engineered, designed to filter up to 1k watt, it is able to clean the ac ripple out of my hu dc input. If anyone's interested I may be able to find the old circuit diagram.


that's all for this post I may have some updates this weekend however it's the girlfriend's birthday this weekend so who knows...

 

i would just ditch the back deck speakers all togther and just focus on your front stage. my setup consists of DLS Iridiums 3-ways with 8" midbasses in my doors. i threw some old boston acoustics coaxials in the back doors for some fill and to please my passengers. i kept the rear deck empty...and it helps vent the bass into the cabin.

 

+1 AscendantMax 8" inch mids in the front door!

I thought I had to shoe horn the home audio 6.5's in there... Do you have any pictures of your build? I am very curious to know how that looks up front

 

yeah, here are a few pics when i was installing them. I used an air saw to widen the door's speaker opening.

 

Pshht to Gordos ( AscendantMax ) little 8s. I do 10s. lol

I Strongly have to agree on the rears as well, unless you have a specific objective for them. Focus on the front, have you ever attended a concert with musicians performing from behind you ?

Acoustic treatment is vital. Install is key and can make even the 'best' drivers available sub par without proper attention.

 

I was wondering when you were going to chime in about your damn 10s

 

Muahahaha

 

Nice build I ALSO agree with ditching the rear speakers. I run 8's in my doors as well, I'll try to get some pics.

 

I'll jam some 12's in there and show you! But on a serious note I might be in touch with you for some gear

 

Oops, didn't see this here. Anytime my friend !