Mr. G's Bargain Build..........

I have decided to uprate the ICE in the Warthog............this came to be during a recent journey....i was cruising along happily and decided to play some Van Burren......it was a pretty heavy re-mix and the pathetic VX OEM set-up was doing poor justice to the track........in fact it sounded as though somebody was sharting through the doorskins..........since i know jack about ICE i have enlisted the help of Sausage Fingers(Greg)and Ikarus(Dave).....i have commisioned Sausage Fingers to carry out the install to prevent me from accidentally setting the VX on fire...
Since the VX is dual purpose vehicle (Mrs G's mega shoe and handbag shopping carrier)any sub type thingys had to be removable,so a custom bespoke install wasn't practical............
The brief for the build is to keep it cheap but still of a reasonable quality.....
Sausage Fingers carried out an exploratory examination of the current system to see if it could be incorporated into the new set-up as the reversing camera is intergrated into the current CD/Radio/TV Monitor...........
Due to lack of decent outputs Sausage Fingers opted for a new head unit..........on removal of doorskins we found the door speakers fubar'ed...........
We decided the new system was to incorporate thr following Headunit....4 new door speakers....amp....2x10" subs.
Sausage Fingers came up trumps by finding a 2x10" Sub-box for £16.00
He recommended a JVC KD-AVX2 single Din DVD unit.....i managed to pick a good used one up on e-bay for £120.00
Sausage Fingers then sourced out a good deal on some new Rockford Fosgate components for £73.00 for the four
Ikarus is donating the Jap-n-Crazy "slag" 1000w amp which originally belonged to Sausage Fingers at some point.. ...........just need some cheap but good subs.......(new noy used).........ideas anyone.........

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Definately a few options out there, had another look this morning.. Depends on how they are powered and on the box type / volume.. Greg, is it a sealed enclosure? any idea what volume you have? Also, what power are they going to have available off the amp? will it power the mids as well or just the subs?

Once i know these factors i'll run the numbers through BBP6 on a few cheap 10's to see what comes up trumps.. will post the graphs too..

Dave

Sausage Fingers Ha Ha!!! Maybe that shouuld be my new forum name.

anyway on to the build i now have in my possesion a bargain JVC DVD headunit, 2 pairs of rokford fosgate 5.25" co axial speakers my old fusion amp and i do believe the wiring kit has also arrived and the sub box is in the post.

dave dimensions of said box are 31" long 11" deep and 12" high

greg

gregmr2 wrote:

dave dimensions of said box are 31" long 11" deep and 12" high

Thanks Greg, i've just ran a few driver options through BBP with interesting results..

First i calculated the box enclosure..

2.583 ft x 0.916 ft x 1 ft = 2.36 ft^3 = 0.0668 m^3 = 66.8 ltr

1. Assuming dimensions are external, therefore allowing 20 ltr for MDF material volume, approximate box internal volume = 47 ltr
2. Assuming subwoofer driver displacement approx = 1 ltr
3. Assuming each box is sectioned to provide two individually sealed enclosures

Each sub box has volume = 22.5 ltr approx

Then i modeled this in BBP..



Next i trawled the net to finder driver specs on a few reasonably priced 10's and modeled them in BBP. Models used are
Alpine SWE-1043E, SPL Dynamics V250S4 and a JL Audio 10W0v2..


SPL Dynamics


Alpine


JL

Notice BBP shows a slider at the top of the driver input dialogue to show what type of enclosure the sub is best suited to.

So now i ran the graphs to see what frequency curves we would get..



BIG difference between these models. (Colours correspond to next image)

Finally, i took a screen grab of all three models side by side. Particularly look at the F3 value - this is the lowest frequency that the system will be able to generate noticably - the lower the better.



So, the results are in..

The Alpine sucked in this setup, but would probably perform better in a ported enclosure.

The SPL Dynamics performed better than the Alpine, but not as well as the JL.

The JL is perfect for a sealed enclosure and performs extremely well. I even found these for sale at £59.99 on ebay brand new..

case closed!

Dude thats awesome...............you've lost me in Techno-babble but all those facts and figures are amazing.........thanks for all your efforts dude.........will go with said JL's methinks...........cheers Dave..........

thats great dave cheers - a little over my head but will definatly need to get together and learn off u for my own install

andy will leave it up to you to get the required subs and will probably make a start on the car next weekend

just purchased a pair...........

With the need for the sub box to be removable from the car,and the need for me to carry other objects around,they will need some form of cover/grile...................what do you guys recomend...........and will it ater the sound(Dave)............. .

You're welcome Mr G.. Those subs will be spot on in the box you bought - the volume is 'almost' perfect for optimum tuning, a good buy!

PS Greg.. dont use any fibrefill in the enclosures, they are actually just a tiny bit on the large side which actually helped lower the F3 very suptly. Any fibrefill will further decrease the tuning frequency of the box and you'll lose that nice transient response curve - it will sound better (more natural) with none. (i modelled this in BBP to test it).

Mr. G wrote:

With the need for the sub box to be removable from the car,and the need for me to carry other objects around,they will need some form of cover/grile...................what do you guys recomend...........and will it ater the sound(Dave)............. .

JL do their own proprietary grilles which fit into the rubber surround. They are designed that at maximum excursion (forward movement) of the speaker cone they do not clip the grille, which can happen on some off the shelf type grilles (sounds terrible and damages the speaker). The grilles you need are these ones i believe:

JL Audio SGRU-10

before..


after..


The code JL use is SGRU-10 - be carefull as there is a SGR-10 (without the U) and they are not the same and wont fit.

They can be a bu@@er to find online because not many places stock them. I think i got mine from the states as there was no real rush. I have these on my 8's which are now fitted in the 350 (behind the seats),have a look see next time i'm in the car at work.

As for sound quality i wouldn't be too concerned. It will be easy to test as they just pull off but I suspect you won't notice a difference. Plus, it's better a little noise reduction than running without them and finding a wayward screw driver lodged through your speaker one day

gregmr2 wrote:

thats great dave cheers - a little over my head but will definatly need to get together and learn off u for my own install

Any time bud, i'm in the final stages of my build and have thouroughly enjoyed the whole project - will find out if i got it all right soon .
I learned so much from the boys on the talk audio forum the past few monthd. It's literally mad science - i love it .

Picked up some cheap grils for now..............will source the JL's out in the future.............
Hopefully sausage fingers can make a start this weekend............

Mr. G wrote:

Picked up some cheap grils for now..............will source the JL's out in the future.............
Hopefully sausage fingers can make a start this weekend............

I had a look as well for the JL's in the UK and couldn't find any. I had the same problem with mine, hense importing them. As long as the grilles you bought clear the cone at 'full chatter' there won't be any problem - and like we discussed, if they don't its an easy job to pack them out a little.

Also i checked the power rating on the JL10W0v2's, they are rated rms 150W, and peak around 300W. You will find that JL subs are well known for taking a lot more than they are rated at (i've read some people are running them at 500W with no issues), however, with the amp gains set properly so they hit 300w at full volume they will be plenty loud enough! Also, with the amp capable of pushing 1000W, at 600W it will not be under much strain and hence produce better sound quality. Amps often degrade the audio signal at high gains - most people think that the speaker is straining, when in reality it can often be the amp (or both) - distortion comes in many forms. This is pretty much an ideal setup for two 10's - will sound great, very lively and punchy and still hit the mid 40hz mark - can't wait to hear it!

I still suggest a small amp for the coaxials, the head unit will be running flat out trying to keep the mid levels up with these subs (amps running flat out = distortion). At the very least i would suggest that you run a thick enough amp feed cable so that you can tee into it later to add an amp without overloading the cable. Here's a thought - if you run the rear coaxials off the head unit and the front coaxials off a seperate amp you would get the sound levels and quality where you need it - up front - and you would only need a small stereo amp.. like this one for £39.99

www.caraudiodirect.co.uk/zero-za400.html

With the head unit only running the rears it would be under less strain and hence the rears would sound better too. Would suggest it's worth 40 squids mr.G

Will look into it dude...........

I take it it woud need another amp wiring kit as well.......?

Mr. G wrote:

I take it it woud need another amp wiring kit as well.......?

Depends on what you already have, you may just need a distribution block. The ground side is simple as you just wire to suitible ground. It's the live side that needs a little more consideration. It's easy to calculate though..

Power (Watts) = Volts (V) x Amps (A)

Both amps at peak will be say 800W

You know your car runs on 12V

Therefore total peak draw will be 800W / 12V = 66.6A

So you need:

1x main fuse at the battery of say 100A (Your need this regardless of how many amps you run, the fuse value differs according to load)
1x distribution block fused at say 40A for the small amp, 60A for the larger amp - wired near to the amps.
1x live cable rated at 4 AWG - runs from battery to distribution block - you likely already have this in the wiring kit you bought. Greg will know this.

So there you go, you likely just need a fused distrubution block additional to what you already have