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General => Car audio => Topic started by: Len on 13 May 2004, 12:08
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Anybody done anything like this?
Thinking about fitting a 10" sub in the parcel shelf.
Now i have thought about this and it will need a thick sheet of ply and some metal bracket supports under neath. Gonna raise the speaker above the shelf a bit so not so much below.
What do ya think - am i crazy?!
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you cant put any sub on the shelf. You need a 'free air' sub i think
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putting a sub in the parcel shelf is like advertising it!
"Come and steal me! .... please"
I would hide it away from the eyes of theives!
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As frequencies below 150Hz are omnidirectional, it is not worth fitting one into the parcel shelf. Instead just install it in the boot and keep it safely hidden from view.
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it does work very well, but like someone said. it's on display a bit. built a solid shelf of MDF and then mount it underneath with cloth over the top.
make sure you buy a free-air sub cos the other types sound sh!te outside a box
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To my knowledge most sub speakers are "free to air" or should be. It would have to be a very large enclosure if not! Most bass boxes are ported and therefore act virtually the same as free to air.
The very best enclosure type for a bass speaker is a Transmission Line. This is used in to of the range Hi-fi and is basically a tuned horn shape which is ported at the small end, speaker at the big end pointing forward. I have sort of made this in my other car.
I take on board what you say about keeping it out of site - but i intend to make this stand out. In my experience if someone wants to break into your car they will and hiding it away is no deterrent, they can hear it when you turn it on!
My other car was in a locked garage, locked and alarmed. They broke in and stripped the stereo. Thats headunit 6x9's in the doors 7x10's in rear shelf 12" sub and 4 ch amp in boot!
If ya got it flaunt it i say!
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Granted, you wont stop a determined thief, but concealing speakers will not attract the unwanted attention of opurtunistic thieves. I always turn the stereo down when I pull into my local area so as not to advertise what I have too.
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Dont want to turn it down! Take a very fatalistic view, if its gonna happen it will!
Also want to keep all the boot space i can, so i see this as my only solution. Dont want a bass box.
Oh i didnt say that this shelf is also gonna house a pair of Sony 6x9's - the new ones with the half open grilles and either a 4 ch amp or two 2 ch amps underneath! ;D
The 10" sub is also gonna be a Sony the current pentagon shape!
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is that all u want to do is safe space lol, then why dont you get a box the will fit side way in the boot so then u will have a box, nice install n SPACE lol or give Auto Acoustics a call for a stealth box or try http://www.autoacoustics.com
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Mmmmm..... yea did think about that - but then i still gotta do the shelf for the 6x9's
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Hi I got 2 Infinity 6x9's either side of a 15'' Rockford sub all mounted on an MDF shelf and looks and sounds sweet.
Go for it.
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Have you had to buy some new struts to pick it up or does it lie permanently flat ???
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My intention is to make up some brackets out of small angle iron so that the new shelf wiill rest on them
( 4 No. ) with a bolt and wing nut fixing to the shelf, so it can still be raised.
The sides the existing shelf sits on wont be man enuff coz its only plastic.
;D
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you say your looking at a sony pentagon woofer for your shelf?
i can tell you that its not designed for free air or if you like infinite baffle as its also refered as well.
the main difference between car audio loudspeakers and ones which are used in home or professional/stage applications is that you will find alot more effort has been put into the design and manufacture for the in-car market this is because of the many limitations on application in everyday cars etc, right thats a bit of the boring bit gone!!
most sub-woofer's for use in-car are designed for use in a sealed enclosure of varying size etc depending on each different speaker!? alot will work in ported boxes with a tund length port, the most common enclosure size is around 1 cu'ft for a 10" woofer this is not a rule but average, yoiu should look at the manufacturer's spec's for the driver to find out there recomended enclosure etc.
well sorry to be boring but been in the car audio trade for about 10 years now played with lots of different equipment and but a few demo cars, if i can help at all i will be more than happy to give any advice asked of?
Ant
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crap spelling as well ha ha getting tired now!!
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Thats a bugga if correct, will have to check it out on the Sony website.
Cheers for the warning!
Shame if its so coz i like the colour/shape. Know i shouldnt put asthetics first - but this is not intended to be a top notch db bashing system. If it was i would use sumthin better than Sony.
Was just trying to keep it all the same with the head unit, which is a CDX M730 - (4 x 52 flip face and mask-off)
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free to air subs are virtually unheard of in the ICE scene. i just had a look around and it seems like they really arent "free to air" but in reality are designed for use in applications like you decscibr. mounted in a boot. performance wise they dont give as good response as sealed or ported designs. you also need to seal between 'below' and above the shelf as good as possible. plus having 6x9s in there too may affect things.
a sealed box is the simplest, easiest and safest way to go.
sealed boxes take up less space than ported ones. the reason i said 'safest' is that there is the possibility of blowing a sub thats in a ported box if you overdo it, whereas you're safe with a sealed enclosure. plus you dont need to get the tuning freq right (distance of port from sub, diameter and length are crucial) the trade off is that you will get better bass response from a ported box. (i.e. lower bass).
i've got 2 small 8" rockford fosgate subs in a custom sealed enclosure. (well two enclosures with a frame holding the amp in the middle... its on rails so heat can escape on all sides)
it looks like this if you flip the rear seats fwd -> | SUB | AMP | SUB |
The enclosure isnt that big.. in depth anyways, but combined its the full width of the car.. each enclosure is 2/3rds of a cu ft each (i think) maybe less. think the depth is around 7 inches at the widest point (bottom), and they're def only 12" high (and 15 wide i think). i have them mounted behind the seats. i still have most of the boot space so there is still a lot of storage room and the spare comes out easily, but the seats cant be flipped forwards. i designed it this way, and spent ages picking the right subs for my purpose.
oh and along with the usual parameters most subs come with simple plans for sealed and ported boxes. most things available from the manufacturers site too.
there are some good online box design things these days.
btw... wouldnt a sub in a shelf vibrate the shelf quite a lot too?
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Well thats really why i asked the question in the first place Overseer mate. Because the vibration/securing issue was what i was most worried about, but seem to have stirred up other issues.
Dont think i can effectively seal the boot, coz i want to keep the practicality of the tipping seats etc.
I was gonna use some 1" thick ply i've got and mount it on brackets coming from the side of the car out of triangulated angle iron and was hoping that would be substantial enuff!
But all this free to air and enclosure stuff is making me think again.
Might have to think about building an enclosure on the left (offside) for the sub and just putting the 6x9's in the shelf!
:-\
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Might have to think about building an enclosure on the left (offside) for the sub and just putting the 6x9's in the shelf!
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sounds like a plan.. one of those stealth side box thingys that fit by the wheel arch might be a good option if theres one for whatever car you have
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A nice pair of 15" pentagon subs go well in my enclosure :P
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Just checked out autoacoustics website for a stealth sub box - Hmmm.... ?150 quid !! dont think so.
Think i'll make one myself.
Before anyone says anything - i have very good glassfibre and woodworking skills.
Depends if i wanna make it removable.
Hmmm... s'pose i'll have to - to get at the strut tops and side light clusters. Yeah!
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I can still get to my top srtuts and take my bulb holders out easily. All just about fits in perfectly. Design is the key to success.
http://www.golfgtiforum.co.uk/gallery/displayimage.php?album=119&pos=0
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lowgolf - but u got no boot left!
Sorry def not going that route!
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Its a good job i dont use it really ::)
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Well i did make a parcel shelf Saturday morning in an hour or so. Bit of 18mm MDF and cut out for 6x9's.
Took it over to my son-in-law and he wired it all in with a non descipt amp he had lurking in the garage.
Not bad - will do for this coming weekend - RTTS.
So will live with it for a few weeks and see if its worth adding the rest.
8)
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you can turn it into a stealth shelf..... by putting some
fine black cloth over the shelf......
and you still hae the sounds but there hidden when you go shopping.......etc
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i have a 10" sony penatgon sub in the centre of my 36mm thick mdf shelf, either side it has a jbl 6x9", sounds ok to me but i dont have it 'mega' loud only enough to over power the noisey scorpion exhaust!!, i am missing my boot space though, amps are mounted on the rear seat back, and the shelf is that fookin heavy i can never be arsed to use the boot!!, if these sony penatgon subs are not 'free to air' then i think im gonna have to give it a tidy up and mount it in the left hand side boot compartment and revert to a thinner/lighter shelf with the 6x9"s in and mount my amps else where!! gonna make a template of the side bit i need and make a panel at work tonight,
Gaz ;D
oh yeah, so if my sub isnt a free to air jobby is it gonna to sound better in an enclosure then?? was happy with how it sounded anyway but if this makes it sound better as well as easing the use of my boot again ill be well chuffed!!!
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oh yeah, so if my sub isnt a free to air jobby is it gonna to sound better in an enclosure then??
yup yup.... check the docs that came with it.. they often come with simple box plans for the right size (important!) these days :)
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will dig the box out and have a look??
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if you dont have any luck its gonna be on the 'net somewhere :)
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Now this free to air/ box stuff - maybe a bit controversial here but whats the difference????
Now i can tell ya that over the many years - i have looked at hundreds of speakers out of hi-fi's, radios, ICE. Now i can tell ya they dont look any different. They all got a cone and a magnet.
Now what they all do is push air. The magnet makes the cone move and threfore causes a vibration that becomes sound waves.
Now in a sealed box the sound waves have nowhere to go, therefore the air pressure must press on the cone. I think what this does is give a more punchy feel to the sound.
So in my opinion it dont really matter how u mount a speaker.
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the air pressure thing is what stops the speaker blowing when you turn it up too loud... it also is to do with sound wave ejected backwards when the cone moves. too large a box and it seems stifled.. too tight and you dont get enough movement.
there are 1000s websites out there with all the relevant calculations on.
believe me, boxes are a lot lot better.. you get waaaaaaaay deeper notes out of the sub.
i ran my sub quietly out of the car when i wired my in, and to be frank it sounded kinda wet. with the boxes installed it booms.... no contest.
I was lucky to have met a bunch of guys into car audio when i came to work where I am.. I suggest you read up a lil on the suibject.
as i said befiore.. no one, but one i have seen ever ever ever has put a sub in a car thats not in a box. its unheard of!!
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The way i see it there are two different types of speaker. A sealed one, and a non-sealed. I thought the sealed speakers were infinite baffle. This means if you have two speakers in a box, when ou push one in, the other will come out etc... These spekers produce a bewtter sound, but need a lot more power to drive them. Can't remember why there better, will find out and let you know. I would imagine it would improve responsiveness, ie with a normal speaker, the speker wuold push out, but theres not much to force it back in. With infinite baffle, it would be forced back in by the vaccum, which should make a "crisper" sound
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yep sealed boxes are the best ;)