389 replies to this topic

[Ben DePellegrini]

Hi guys,

If you haven't seen my intro thread:

http://www.mobileele...from-melbourne/

I'm Ben.

I'm here because I love car audio, and essentially the SPL bug has bitten. My current setup has been run at 136.2dB on a Termlab, and someone has made mention that 150dB hasn't been done in an Aussie sedan yet. Basically, that's why i'm here.

What would it take for someone such as myself to achieve a peak SPL reading of 150dB (basstone or music, not fussed) in my sedan, yet still be able to turn it down and enjoy some street-beats day-to-day. My car is an FG XR6 turbo, and boot-space and finances aren't really an issue with this quest.

Any & all questions or feedback is welcome,

Thanks,
Ben

Edited by Ben DePellegrini, 04 April 2013 - 11:50 AM.

[Banana_Boat]

i think 154 was the loudest sedan lol I think his name was josh ? or VTjosh in this forum. Correct me if im wrong though. He done his in a VT commodore with 2 15's and 4 monoblocks

[SPLWGN.inc]

- buttload of power
- multiple woofers
- well designed box with subs and port firing towards cabin
- back seat removed
- box sealed off from the boot.

Assuming a combination of the above things should get you on your way to a 150db? If you check out SMD a couple of the guys on there have 150+db trunk builds, could get some ideas off there?

[Lunchbox.inc]

i think 154 was the loudest sedan lol I think his name was josh ? or VTjosh in this forum. Correct me if im wrong though. He done his in a VT commodore with 2 15's and 4 monoblocks

correct, BUT that was done with the enclosure replacing the backseats in a SSNW style build... definitely not a "sedan" for all intents and purposes... in reality it's no different to a hatch

for a true sedan setup with everything in the boot, the loudest we have in Aus atm i believe is a mid 147...

as SPLWGN has mentioned, a "miniwall" is definitely the way to go, but asks for alot of dedications, as to do it "properly" takes a fair bit of dedication.... BUT your in luck with having an FG falcon, as they have the 60/40 folding back seats, meaning you have plenty of room, AND i'm pretty sure the parcel shelf has some nice big holes in there for both the factory sub, and the midbass in there too......

basically i'd be walling of the trunk, 2x 15"s firing forward, with as big a port as you can fit firing up thru the sub hole in the parcel shelf...

i'm sure plenty of member will be MORE than happy to assist in any help you may need with design/ideas...


EDIT: i'm also the guy who mentioned on the MEA facebook that a 150 hasn't been done in a sedan from the trunk... lol

Edited by Lunchbox.inc, 17 April 2012 - 07:29 PM.

[Ben DePellegrini]

... BUT your in luck with having an FG falcon, as they have the 60/40 folding back seats, meaning you have plenty of room, AND i'm pretty sure the parcel shelf has some nice big holes in there for both the factory sub, and the midbass in there too......

basically i'd be walling of the trunk, 2x 15"s firing forward, with as big a port as you can fit firing up thru the sub hole in the parcel shelf...

i'm sure plenty of member will be MORE than happy to assist in any help you may need with design/ideas...


EDIT: i'm also the guy who mentioned on the MEA facebook that a 150 hasn't been done in a sedan from the trunk... lol

Thanks Lunchbox, that's a good start. I'm not opposed to walling off the trunk at all, but does that involve turning the boot into one giant sub box? (I.e. lining the boot with MDF), or just building a very large box, and just have it be mostly the size of the boot? To have two 15"s firing forward would require the box be built into the cabin, as the gap through to the boot is only 310mm high.

You're correct about the premo-sound, there was a sub there once, but now there is an 8" hole, perfect for a port. I can handle sourcing grunty 15's, and amps aren't an issue. My current 15"s are 1000w rms each (RE SXx 15"), but they're only getting 1200w rms each, so please advise if you think they will be suitable or not.

Any help with box volumes and port dimensions would be really handy.

[Lunchbox.inc]

ideally when going a miniwall, it's basically built almost entirely inside the boot, it takes ALOT more planning, but it ensures you get as much box space as possible... if it were me, i'd actually be fiberglassing an enclosure or at very least the floor and parts of the sides...just to minimize the loss of airspace.... but the baffle, top, back and part of the sides would still be MDF, ubt there's no reason why would couldn't do the whole thing out of MDF, you'd just lose a little bit of space...

a single 8" round port firing directly up thru the hole left in the parcel; shelf would be perfect... and i'd be trying to find around 8-10cf worth of enclosure in the boot, without a doubt thats a BIG ask, but thats what i'd be aiming for... and remember, the box can NEVER be strong enough, if you want serious scores (150 from the trunk is serious) then it needs to be strong, triple layer baffle, double everything else would be about minimum, pretty serious stuff...

as for woofers/amps, i always consider that something that can be changed at any time, as long as you have SOMETHING, then thats fine, and your current gear is perfectly fine for the time being... for example, my corolla with it's properly built setup which does 156's on full power, was happily plotting along doing high 148's off only 700rms... getting loud has got ALOT more to do with the enclosure, and the install, than the gear used...



i've actually been contemplating buying an older falcon and having a whack at hitting the 150 mark from the boot, but it's something thats not entirely viable for me atm, down the track perhaps?

[089JAY]

I'm gunna take 1 smallthing Lunchy said and turn it around.

"and remember, the box can NEVER be strong enough"

I was talking to George about this on the weekend and testing is key here, he made mention that in one of his cars, if he used 16mm or 25mm MDF his score was down on using 18mm MDF...

Testing absolutely every single little change, every possibility and every situation is going to be the key to your build mate, one small change can be (and has been in the past) worth 0.5db - 1.5db (even more in some cases) and from the Trunk, once you're doing anything over 145db every 0.1db is a big deal.

Good Luck with your quest, can't wait to see how it turns out.

[Lunchbox.inc]

I was talking to George about this on the weekend and testing is key here, he made mention that in one of his cars, if he used 16mm or 25mm MDF his score was down on using 18mm MDF...

Testing absolutely every single little change, every possibility and every situation is going to be the key to your build mate, one small change can be (and has been in the past) worth 0.5db - 1.5db (even more in some cases) and from the Trunk, once you're doing anything over 145db every 0.1db is a big deal.

thats a good point actually, but i believe a properly trunk walled car behaves in a similar fashion to a fully walled car, where you want the enclosure to couple with the body in a similar way, just the cabin area is obviously significantly different between the 2, and enclosure strength comes heavily into play... but thats not to say your point isn't also right, it's well documented that strength doesn't always mean louder if it comes at the expense of losing a resonance within that box...

kind of in a similar way to how some cars will be louder if your pressing on the panels stopping the flex, but some will get quieter... there's ALOT of experimentation that goes into getting any car seriously loud, and there's MANY different ways to achieve the same thing...

[RAD]

Straight off the bat, if you're even contemplating trying to get 150 from the boot of a car, you need a second, sacrificial car. Unless you've got some extreme fabrication skills, you'll likely need to screw and glue the enclosure for it to become a part of the car. Plus, you'll have to seal the parcel shelf to prevent pressure entering the boot.

Something i bet you won't want to do to a new XR6T.

[bassbro]

ideally when going a miniwall, it's basically built almost entirely inside the boot, it takes ALOT more planning, but it ensures you get as much box space as possible... if it were me, i'd actually be fiberglassing an enclosure or at very least the floor and parts of the sides...just to minimize the loss of airspace.... but the baffle, top, back and part of the sides would still be MDF, ubt there's no reason why would couldn't do the whole thing out of MDF, you'd just lose a little bit of space...

a single 8" round port firing directly up thru the hole left in the parcel; shelf would be perfect... and i'd be trying to find around 8-10cf worth of enclosure in the boot, without a doubt thats a BIG ask, but thats what i'd be aiming for... and remember, the box can NEVER be strong enough, if you want serious scores (150 from the trunk is serious) then it needs to be strong, triple layer baffle, double everything else would be about minimum, pretty serious stuff...

as for woofers/amps, i always consider that something that can be changed at any time, as long as you have SOMETHING, then thats fine, and your current gear is perfectly fine for the time being... for example, my corolla with it's properly built setup which does 156's on full power, was happily plotting along doing high 148's off only 700rms... getting loud has got ALOT more to do with the enclosure, and the install, than the gear used...



i've actually been contemplating buying an older falcon and having a whack at hitting the 150 mark from the boot, but it's something thats not entirely viable for me atm, down the track perhaps?

hey bro i actually had a corolla sedan hitting 153.4 off 2 old school soundstream spl 15" and a 2.5k dragster amp it smashed real hard....the scores were official here in qld.... a car audio installer back in mid 90z had the loudest sedan in aus with 150.2db.....i smashed that score lol.....in sayin this my ride always had a seat in the 150zone......and yes they were audio control but hey id be willing to give it a crack with the same gear on a termlab

[Lunchbox.inc]

hey bro i actually had a corolla sedan hitting 153.4 off 2 old school soundstream spl 15" and a 2.5k dragster amp it smashed real hard....the scores were official here in qld.... a car audio installer back in mid 90z had the loudest sedan in aus with 150.2db.....i smashed that score lol.....in sayin this my ride always had a seat in the 150zone......and yes they were audio control but hey id be willing to give it a crack with the same gear on a termlab

current termlab is around 4db-ish lower than audiocontrol if i remember correctly? still damn impressive scores Willie!

[Ben DePellegrini]

All of the above is great!

After doing a 30-second sketch as to my available boot space, i've come up with around 367 Litres of accessible gross boot space. This is with a rough MDF box, square edges etc. If someone can tell me how to upload images, ill paste it here.

367L = 13 cu ft gross, so id probably bargain that down to 10 cubes after sub & port displacement, double/triple baffles and braces etc. No clue as to how id install it in the car, or get it out of the car afterwards, as it takes up literally the entire boot (minor details...). SMD specs say that my subs will need 4cu ft of box each, so an 8 cu ft box wouldn't be terribly difficult. The difficulty will probably come from sealing the box off from the boot and sealing it to the hole behind the seats.

If i'm going to have one top-firing 8" diameter circle-port, how do i work out port volume for an 8" diameter?

[bobo333]

having done a miniwall in an FG before i can say youll have lots of trouble fitting 2x 15s in there, we couldn't even fit a 12" in without cutting metal or angling the baffle... a pair of 15s will require lots of metal removal which will legally write your vehicle off so id be more inclined to either think of some cool angled baffle setup or go to a bandpass with the port through the seat opening

heres some pics of the one weve done:






with a memphis mojo 12" and a 2500w mono it has done a best of 140.6db so far, still plenty of tuning to go though

good luck

[woodzyspl]

i used my dc 9k on 18v wired to 1ohm with a soundstream xxx 15" sub, i got a 147 as a pb with sub up port back and rear seat down. now that is with a box not nearly complete (no flush mount no bracing and was to small) and no port changes just drop in. also wanted 2 more batterys to help voltage and drop it down .5ohm or lower. it can be done and it not that hard if all want is burp, i played music off bout 4-6k daily off that setup without any worries (couldn't go below 35 hz really above what id say is 4k tho LOL)

i was going to do it and was going to do it in the worst car for it..but it was written off and now im back to building a ground pounder.

the next closest would be nathan who had a ford (all seats go down) who dd a 18-149 iirc with dd8k amp and 2 re 15" sub up port facing back aswell.

imo you could buy a solid 15" sub (or 2 12") such as a dc level 5 or xl, dd 9515 (or a z if afford) or better a fi n3, then i would get atelast 10k worth power per sub, best option for me was a 9k at 12v amp running up to 18v so even if voltage drop i would always see the 9k.. unless you fire it all forward, then id go on SMD fourm and look for mrio build (done 150+ out a boot on music with 2 10") now doing 150ish with 12 or 15" but i think he rebuilding

[Banana_Boat]

does it count if the batteries and amps are on the back seat ? but the subs and box still in the boot ?

[bassbro]

current termlab is around 4db-ish lower than audiocontrol if i remember correctly? still damn impressive scores Willie!

there have been a number of tests regarding this and on average it seems the audio control reads 1.5 to 2db higher than termlab dunno if thats a goodn thing or bad haha......but ye i actually have the exact same model car sitting at home i might have to throw it up again lol

does it count if the batteries and amps are on the back seat ? but the subs and box still in the boot ?

good point im sure someone has rules stated somewhere

[woodzyspl]

if its a true trunk install, no, otherwise may aswell put it all in back seat and go nw..

BUT if you do what others do overseas..this could be an option if need be lol

also if in street boot class at db drags, not sure here but USA is 2 batterys 1 in stock, 1 in boot, and max 4000rms

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[Banana_Boat]

well really it shouldn't matter what setup you have in a sedan, at the end of the day it's still a sedan. wall or no wall.

[Lunchbox.inc]

but walling a sedan means its a walled car, not a sedan, or at least when audio is concerned... pipo sanchez and tommy mckinney don't have loud utes, they have loud walled cars... acoustically, there's no difference between body styles at all once walled, so being in a sedan means jack all, other than having to work harder to build the enclosure, for no greater pay off...

for me, all the gear needs to be in the boot, OR hidden out of view and have all 5 seats usable without and issues (obviously seatback would need to be folded back into position for this)... if your running small footprint amps that can hide under the front seats, then good work, but having amps in the rear footwells would be full of fail...

[Banana_Boat]

but walling a sedan means its a walled car, not a sedan, or at least when audio is concerned... pipo sanchez and tommy mckinney don't have loud utes, they have loud walled cars... acoustically, there's no difference between body styles at all once walled, so being in a sedan means jack all, other than having to work harder to build the enclosure, for no greater pay off...

for me, all the gear needs to be in the boot, OR hidden out of view and have all 5 seats usable without and issues (obviously seatback would need to be folded back into position for this)... if your running small footprint amps that can hide under the front seats, then good work, but having amps in the rear footwells would be full of fail...

I get what you mean by that. but what about a SSNW setup ? cause you can take the box in and out of the back seat as need be ?

I wasn't talking about putting amp's in the footwell. There are many people in the US that can hide amps under there seats.

But hey when people over hear get as loud as the American's then i guess we can come up with good idea's like that

But hat's off to the OP for having a good to try can crack the 150db in a boot install..

Does anyone know the loudest sedan in the world ? that would be a good score to beat

[Lunchbox.inc]

i know of a mazda 6 doing 153 from the trunk iirc...? but don't know of any louder...

even a SSNW setup, the cabin is no different to any small hatch competing in SSNW, infact i'll throw it out there, it's probably easier to get loud SSNW style in a sedan, because you can seal the cabin from the boot for equal or less cabin space than a hatch, and still have plenty of room for amps and batteries away in the boot, Aus's loudest SSNW car was a sedan, Andu in his pintara...

unless the install is entirely in the boot space, then there's nothing special about it being a sedan.... can still be a cool build etc, but unless its in the trunk, the fact it's in a sedan means squat...

[Banana_Boat]

Im surprised you haven't tried somthing like this lunchy surely you have a huge range of subs there to try from ?

[woodzyspl]

lol agree with lunch 100% loudest score from the boot of a sedan..

[Banana_Boat]

hahaha funny enough jame's i just bought one of those civic sedans haha hello 159db

[Lunchbox.inc]

funny you should mention that only a couple of months ago i was eyeing off this...

 25092011217.jpg   1.93MB   6 downloads

with the intention of aiming for a low tuned musical 150db daily, came SO close to buying it as i think it would have been PERFECT for a build, but as i'd just come off the charade build, i couldn't bring myself to put THAT much effort into a car to "just" see a 150... i wanted to build something bigger and better, aiming for a 160... but now the 160db groundpounder has been put on the back burner as i gather the gear for it, i wish i had have grabbed the damn ED and build a trunk car...

so it goes without saying i'm following this build with ALOT of eagerness...

[Banana_Boat]

haha you should so buy that .. 150db coon chariot hahaha.... I was aiming for a 150db in my car. But decided to go daily over number's. Now i regret it haha.

surely you should have enough gear to put in many car's lol let alone get a 150db from one car lol

[Lunchbox.inc]

lol, c'mon, i've only got 7 bonecrushers and 13 beastmasters... or should i say 8 working beastmasters!! eep, i barely have enough woofers to keep Siddy running atm!!!

nah it would have been a great project, and if Aus hasn't seen a 150db sedan in the next year or so i'll definitely buy one, at the time i was just sick of seeing guys whinge that their cars weren't competitive in SPL because they were sedans... it goes without saying that a hatch will almost always be louder, BUT unless your really at the top of the field there shouldn't be a huge difference... 143-145 isn't crazy out of a sedan, it's big but not crazy, and generally thats enough to place well in the classes those cars would fit into anyways... but most of the those complaining you could tell had put in no effort because they thought it wasn't worth it... i really wanted to show that with a little bit of effort you can achieve alot...

ahhh... one day i'll give it a go...

[Banana_Boat]

8 O.O crazy much i think you should off load 2 of them to me

my highest score out a sedan is 143.1 lol but that was with a slap in install with box leaking worse then a hooker and so on lol. But hey for a bogan's car they do allright the good ol commodores haha

People just think sedan, Big space need's lots of power the get loud lol. but you know your crap ( which you do ) anyone can loud out of any car. just take time, it's like Trial and Error

[Ben DePellegrini]

159 is somewhat mental... Whats the reason behind door-open, vs door-closed?

Can someone help me with some port-area-length figures if I can find 8cubic ft (net), for a rectangle cabin-firing port? The subs in the box will sit about 30cm back from the boot-opening, with the port & subs firing into the cabin through the backseat opening. I'm going to aim to build a "corridor" between the front of the box, and the backseat opening, not dissimilar to what a tent with an annexe is shaped like.

We'll call this trial & error # 1.

Oh! Does anyone know where I can access a Termlab or equivalent meter between Dandenong and Traralgon, without going out and spending $800 on my own?

[RAD]

Parrots in Ringwood should be able to book you time on a termlab, perhaps Phat in Braeside too depending on their schedule.

My idea (though not correct to some) is that the cabin is a seperate enclosure or chamber to the sub box, similar to a series tuned bandpass. Sometimes this effect makes the cabin more efficient as an enclosure, sometimes less.

leave port area and length alone for now until you've got a final figure on enclosure size, and you'll likely have to build or change the port many times over to acheive correct tuning frequency, and experiment with port area, flaring, placement and more.