invisible e30 sub

[Boost Junky 1]

WTF? So they pass your WOF for not having one but the Cops can try fine you for not having one? So what about road legal showcars who's boot is just full of subs & amps...

Yea not sure Malcolm would have to look deepr into the Acts which i cant be bothered doing lol. Let me know if you do find out though.

[rogan 7]

If you're looking for space saving then get an Infinite Baffle sub and mount it on a board over the ski hole. Like this:

Most BMWs are perfect for IB as the boots are so well sealed from the cabin.

[antil33t 90]

That is hot!

Would be worried about it being damaged though... but it wouldn't be hard to make something up!

[e30plz 1]

That's pretty sweet and alot easier than making a box or like what Ari posted, How does it sound?

Have a spare 10 inch sub might try that out in the holidays, Just need an amp. And everything else

[Shady 0]

Is it just bolted to the wall part? If so, it would need to be a special sub made to be reverse mounted or it might sound like ass. Not all subs can have the magnets facing out.

[rogan 7]

That's pretty sweet and alot easier than making a box or like what Ari posted, How does it sound?

Have a spare 10 inch sub might try that out in the holidays, Just need an amp. And everything else

AFAIK you can't just use any sub for IB, you need one that's been designed so it can run that way. IB will generally tend to give you much more low end (say 20-50hz) with about a slight drop in higher end (say 50-100hz). I've only tried one IB set up and the sub sounded better than when it was in a sealed enclosure. Downside is you can't put as much power into the sub - say you have a 500rms sub then in IB you wouldn't want to give it more than about 350rms.

Edited September 23, 2009 by rogan

[rogan 7]

Is it just bolted to the wall part?

Yep, bolted to the wall. All you're doing is sealing off the front of the sub from the back.

If so, it would need to be a special sub made to be reverse mounted or it might sound like ass. Not all subs can have the magnets facing out.

Don't understand what you're saying.

Having the magnet side of the sub facing forward or backward doesn't make any tangible sound quality difference.

[pureboiracer 0]

I thought they all had it? Oh well only one way for Malcolm to find out. BTW Apparantly it is not required by law to have a spare for WOF but you are legally required to have CARRY a spare TYRE and a JACK. Reason being if you get a puncture on the motorway you can get your vehicle mobile again... this is just something i was trying to argue with a workmate the other day, he rekons a cop was going to fine him for not having a spare wheel.

i think its something along the lines of you do not need a spare wheel, it is not a legal requirement by law or for wof, ie you can carry a can of puncture repair in a can if you want, but should you break down on somewhere that can cause an accident or is dangerouse to you or the public and it is something that you could have avoided ie puncture, ran out of gas, then i think you can be prosecuted under the careless driving law, kind of like a negligence thing.

[pureboiracer 0]

Don't understand what you're saying.

Having the magnet side of the sub facing forward or backward doesn't make any tangible sound quality difference.

i think he is getting confused with free to air subs, as long as one side of the sub is sealed from the other then it will work fine either way, only when both sides of the sub are not in some sort of box or sealed unit will it sound useless, and thats when you get a free to air sub.

[laadeelaa 0]

Bahaha! I just found this thread.

Sub in the wheel well?

I'm sorry. But that is such a waste of time.

In my e36, I had two 12"s in the boot, and I'm a god damn female, I managed to shove everything in the boot.

[antil33t 90]

I had 1x 12" in the rear of my Lancer, abet the boot was smaller, but I couldn't fit my PC in there. hahah.. /nerd.

[e30plz 1]

I'm sorry. But that is such a waste of time.

In my e36, I had two 12"s in the boot, and I'm a god damn female, I managed to shove everything in the boot.

.... It wouldn't be that hard.

[pureboiracer 0]

what about those with the south african e30s?

[*Glenn* 854]

I thought they all had it? Oh well only one way for Malcolm to find out. BTW Apparantly it is not required by law to have a spare for WOF but you are legally required to have CARRY a spare TYRE and a JACK. Reason being if you get a puncture on the motorway you can get your vehicle mobile again... this is just something i was trying to argue with a workmate the other day, he rekons a cop was going to fine him for not having a spare wheel.

Sorry thats not quite right. Alot of new cars do not have spare wheels or jacks

[rogan 7]

i think he is getting confused with free to air subs, as long as one side of the sub is sealed from the other then it will work fine either way, only when both sides of the sub are not in some sort of box or sealed unit will it sound useless, and thats when you get a free to air sub.

Freeair and Infinite Baffle (IB) are pretty much the same thing.

Sub in the wheel well? I'm sorry. But that is such a waste of time.

I have a pair of 12s in my e39 boot and have enough space for a 3 wheeler pram.

From a e36 M3 in the US:

http://forums.bimmerforums.com/forum/showt...1946&page=8

what about those with the south african e30s?

Excuse ignorance, what's the difference?

[Boost Junky 1]

Sorry thats not quite right. Alot of new cars do not have spare wheels or jacks

Yea didnt think so... I think Oli is on the right track being a neglegance situation.

[|ncary 0]

i think he is getting confused with free to air subs, as long as one side of the sub is sealed from the other then it will work fine either way, only when both sides of the sub are not in some sort of box or sealed unit will it sound useless, and thats when you get a free to air sub.

You'd struggle in a E30 then, there are large vents at the back of the parcel tray into the boot for exhausting air from the AirCon/Heater Fan. A purpose built sub box would be the only way really...

[pureboiracer 0]

just to clarify my 1st post is only a thought at this stage, i dont see why it would sound as bad as some people are saying aslong as you insulate it and build it right, but thats my opinion. i guess theres only one way to find out exactly how it sounds.

[|ncary 0]

I'm no car audio expert (last thing I would ever put in my car is a sub), but I'm an A average physics student, and even though people say 'bass sound doesn't have direction, doesn't matter where you put it', you'll find that it does indeed have direction and amplitude. So pointing a sub directly upwards in the boot is just going to throw sound waves mainly upwards and some sideways and then they shall rebound and become very muddy and eventually make there way, full of constructive and destructive interference, into the cabin.

By having it bolted to the rear wall of the cabin with no metal sheeting in the way, you would have nice clean, non-interfered with, waves to get to your ears then out the windows.

That's basicly what people are trying to say here, like, why it's a poor idea.

[DRTDVL 0]

I'm no car audio expert (last thing I would ever put in my car is a sub), but I'm an A average physics student, and even though people say 'bass sound doesn't have direction, doesn't matter where you put it', you'll find that it does indeed have direction and amplitude.

I always found that odd... i could always hear where the bass was coming from... it's not like its a magical sound throwing device...

[tire 10]

My really early (1983) e30 has no perforated ski hole to punch out. Last two did. Maybe it only came about in the latter years.

Anyway.

[Shady 0]

just to clarify my 1st post is only a thought at this stage, i dont see why it would sound as bad as some people are saying aslong as you insulate it and build it right, but thats my opinion. i guess theres only one way to find out exactly how it sounds.

If you do as I said, make a small box out of 'glass in the well then sealed the sub into it, it should helf stop the tinny sound of the Well. Thats how I saw them do it in a Hot4s magazine. Looked like crap at the start but the end result after tidy up, it looked mint. But of course, its a magazine so they cant let you hear what it sounds like.

Do It. If it sounds crap just remove it. Should be too expensive to build the sub in wheel well, probably $20odd of resources & a weekend in the garage. I'd do it to find out but I got other things I need to do first.

[rogan 7]

I'm no car audio expert (last thing I would ever put in my car is a sub), but I'm an A average physics student, and even though people say 'bass sound doesn't have direction, doesn't matter where you put it', you'll find that it does indeed have direction and amplitude. So pointing a sub directly upwards in the boot is just going to throw sound waves mainly upwards and some sideways and then they shall rebound and become very muddy and eventually make there way, full of constructive and destructive interference, into the cabin.

By having it bolted to the rear wall of the cabin with no metal sheeting in the way, you would have nice clean, non-interfered with, waves to get to your ears then out the windows.

That's basicly what people are trying to say here, like, why it's a poor idea.

What you tend to pick up are rattles from panels that localise where the bass is coming from. Generally you can pick the direction of frequencies above about 160hz. The lower you play your sub, the harder it is to pick where it's coming from. The problem is that it's very hard to stop rattles and that's what you'll be able to identify.

The constructive and destructive interference is somtimes called combing. Some point subs into a corner (corner loading) with the aim being the amplify the wave by combining the primary wave with the reflected wave. I've never noticed muddiness being a result, but positioning of the sub has a big effect on amplitude of the signal in the cabin.

What tends to happen with alot of car is that subs are played too high and even crossed over at 80hz there's still going to be higher frequencies going through it as a result of the crossover slope (usually -12db/octave). In a nutshell, the better midbass you have upfront, the better your sub will blend into your cabin

[|ncary 0]

Now that's a good answer ^, sounds like you know your car audio.

All I'd want to do with a sub is find the resonant frequency of a terribly modded E30 and shake it to bits

[charles28 136]

Picture of me preparing for the installation of my sub and amp etc.

That's only a 10inch sub, but its a decent one, dual voice coil, despite having the ski panel non removed it totally blasts out the sounds in the car and as you can see it doesn't take up alot of space either.

All i have is Front DLS components, Infinity Reference Amp and Image Dynamics sub. this basic setup really kicks ass for the money.