Dissapointed With Sub

[Carbon 34]

You didn't mention the exact areopro box, some I'm assuming this one

Aeropro

if you notice its not a litre, so it would be a very poor sounding box, if you have the sealed version , take 1 bag of loose polyfill stuffing from spotlight or ? and lightly fill the box after carefully removing the sub. your not looking to fill it tight, just handfuls chcucked into it , use 1 bag full roughly about 7-8 bucks I think. don't fill it so full the sub frame hits the stuffing, this will trick the box into thinking its over a litre in size. you could also invert the sub to gain a little more box space but risk hitting the back of the speaker with crap in the boot ? you must have a good airtight seal ?

as you can see below a ported box is bigger but the sound would be a bit better, slightly louder as well.

reccomended box sizes

Ported Box

Fusion EN-SW120

Volume (litres) 48.28

Volume (cu.ft.) 1.705

Port diameter " 76.2mm / 3"

Port length 225.3mm / 8 - 9 "

Tuned frequency (Hz) 33.0

Sealed Box

Volume (litres) 28.58

Volume (cu.ft.) 1.009

Tuned frequency (Hz) 53.9

if your running both the crossovers on the deck and amp, it will cause phase issues, try running the amps - sub crossover at 80-100HZ and no radio xover, but sub out on.depending on which rca your using ?

with both on it can sound muddy bass. along with a small box it would lack , any hit

and run the front deck speakers on hpf to block the bass from the fronts speakers, if you can set the freq on them to 120-160hz. the speakers natural roll off will still play below that but not much. and safe the distortion at high levels.

oops sorry that amp is only 300 @ 4ohms, , but the matching one to yours is the same only a green case. you can use the other old amp on the front speakers ? would make a huge difference in loudnesss

tonight I'll plot your car out for max , bass , using your numbers, out of time now..lol

hope this helps a bit. cheap fix is loose polyfill

[Johny Bravo]

Very annoyed. wrote a long reply. nothing showed up. TWICE!

The prduct code for the box is, SB12100, advertised as a 1 cubic foot box. (tried linking it, kept being gay)

Got that seeing it was close to 1.009 and i couldn't find anything else as close.

My head unit has 3 rca outputs, Rear, front and sub. Rear and front are connected to my 4 channel amp. Sub output connected to the sub amp. I can turn the sub on/off with head unit along with invert it (aim the sub into the box) and adjust the filters. Gotta work out what the filters are cutting what to where. ie what channels. And i haven't seen any crossover function but will have a look.

Got a friend who works at spotlight so i will get here to score me some poly fill on the cheap.

Cheers once again.

Edited March 21, 2011 by Johny Bravo

[Carbon 34]

your sub is designed for PORTED boxes. not sealed

your sealed box MAX DB is just under 115db at 20-100HZ, the bass is very flat and prob sounds horrible judging from the graph it ran.

the freq, you get at your windscreen is 186hz based upon your numbers, so your bass is more MID-BASS when your in the front seats

but at 7 metres from your car windows down the bass most likely sounds much better. shame you can't drive that far from the car. that puts it at 50hz

at 4 metres you would have a big boost at 80hz

in other words build a ported box, face the driver towards the rear of the car, as well as the port on that side as well

and you should be a lot better , deeper sounding bass. and power the sub with more power, still use poly fill on all the walls except the front in the ported box, but spray glue it on. don't compress it, just fluffy handfuls is fine. hope this helps

if you need help on box design I can forward the plans to you.

this is the size of the optimized ported box.

MAX DB for this box is about 120db at max power but less bass in the 45HZ region.

Driver Properties

Name: few-12

Type: Standard one-way driver

Company: Fusion Car Audio & Security

Comment: Encounter series

No. of Drivers = 1

Fs = 28 Hz

Qms = 4.027

Vas = 123.9 liters

Xmax = 11 mm

Qes = 0.249

Z = 4 ohms

Pe = 200 watts

-----------------------------------------

Box Properties

Name:

Type: Vented Box

Shape: Prism, square (optimum)

Vb = 45.36 liters

Fb = 32.6 Hz

QL = 6.873

F3 = 23.62 Hz

Fill = normal

No. of Vents = 1

Vent shape = round

Vent ends = one flush

design 2

MAX DB about 124db at full power using the current amp at aprox 45hz

Box Properties

Name:

Type: Vented Box

Shape: Prism, square (optimum)

Vb = 43.68 liters total 46 litre's

Fb = 32.6 Hz

QL = 6.873

F3 = 30.43 Hz

Fill = normal

No. of Vents = 1

Vent shape = round

Vent ends = two flared

Dv = 76 mm

Lv = 243.6 mm

[Johny Bravo]

If you already have the plans that would be appreciated. But i don't want to put you out any more as you've already done so much. I'm following all that stuff to a limited extent. Which option would you recommend? should i turf the sub, amp and box and start from fresh? or should i just build a box to better suit the sub i have and get a better amp? Building a box should be easy enough for me to do. A tad broke at the moment so i can't really afford an expensive amp for a little while. Thanks once again for all the help. Is there anything i can do to thank you? Cheers.

[Carbon 34]

If you already have the plans that would be appreciated. But i don't want to put you out any more as you've already done so much. I'm following all that stuff to a limited extent. Which option would you recommend? should i turf the sub, amp and box and start from fresh? or should i just build a box to better suit the sub i have and get a better amp? Building a box should be easy enough for me to do. A tad broke at the moment so i can't really afford an expensive amp for a little while. Thanks once again for all the help. Is there anything i can do to thank you? Cheers.

Yeah I have the plans , I'll send them but confirm the opening size before building it, since I dont' have a R31 sitting in fornt of me..lol need height and width betweeen the arms of the boot lid, and depth from window lip to the seat back top.

the box would be the easiest route , sell off the sealed one and build a ported one the right size. then buy a bigger amp down the line, you can never have too much bass...haha

[Johny Bravo]

Yeah will measure as much stuff as i can and send you the dimentions as soon as get around to it. Little drunk at the moment so i think i'll wait till the morning. I think i'll take a picture and draw all the dimentions on top. Should make it easier for you.