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View Full Version : third brake light vibrating form subwoofer ?



djmh
January 30th, 2010, 01:53 AM
ok so my third brake light ..the whole panel its attached to actually, vibrates when my sub hits but the third brake light and defrosters are right on the rear window so it makes a terrible rattling..
its hard to describe ... right now i have some foam type material in between the third brake light and rear window (the legality of that is probably questionable lol)
but it does stop a good portion of the vibration, not all of it though, beacause the defrosters are uncovered (i like being able to see out my window) and it dosent hold the brake light entirly down ... so would you have any suggestion as far as getting rid of the rattling noise caused from the panel vibrating ?

im going to take a look in the trunk tommorow, and see if maybe i can bolt it down better ?

but if you have any experience or ideas i would appreciate it !!

i think dynamat and fatmat etc is a bit too expensive for me...but i also dont think it will solve my problem ?

open to any suggestions !!

thanks !!!

jrusso2
January 30th, 2010, 01:55 AM
I wonder whats going on inside your ear when this happens to the interior of the car.

djmh
January 30th, 2010, 02:04 AM
ya, i dont know ?

but Im really unsatisfied with my speakers lately..there getting quieter every day ?

;)

sailthesea
January 30th, 2010, 02:05 AM
You could try and find the resonant frequency that is causing the problem and cap it out with some in line crossovers (you'd have to build them yourself) You would get a flat spot but it would be very low Hz and you wouldn't notice


OR: Get in there and glue/nail/screw/gaffer tape everything down tight


Myself, I'd just turn things down a bit;)

sailthesea
January 30th, 2010, 02:05 AM
i wonder whats going on inside your ear when this happens to the interior of the car.

say what????:d

djmh
January 30th, 2010, 02:12 AM
could you guys please type a little louder ????

gosh..things are just so quiet anymore :)

haha, eventually i wont hear the rattling, right ?

but ya ill just have to strap it all down ...

judge jankum
January 30th, 2010, 02:18 AM
huh? huh? HUHHHHH?

sailthesea
January 30th, 2010, 02:25 AM
could you guys please type a little louder ????

gosh..things are just so quiet anymore :)

haha, eventually i wont hear the rattling, right ?

but ya ill just have to strap it all down ...

OK THEN!!!

On a serious note though fella

You could be doing serious damage to your hearing and you WILL come to regret it later in life..
I'm in my late 30's and used to sound engineer at venues and clubs
I used ear protection quite a lot when I was going to be exposed to high dB for a long time
All the same I have nearly 50% hearing loss and it makes it hard to have a conversation, listen to the music you love, cross the road, hear the Kids moaning.......oh, it's not all bad then;)

But you get the picture?

Kai69
January 30th, 2010, 02:29 AM
OK what you need is double sided foam tape dont know in the US where to get some car paint factors sell it in the UK comes in differant widths or cheaper option draught excluder the thin foam stuff you put around doors DIY stores
Because its a Bass unit its going to vibrate something as im in the trade we hear more number plate screws rattle :lolflag:

djmh
January 30th, 2010, 02:30 AM
you dont know how often i hear this ....

but yah, i dont think its that loud - not nearly as loud as at a club or anything like that :)

sure hope i dont find out im wrong too late ........

SoFl W
January 30th, 2010, 02:33 AM
Install "mute" and reboot.

djmh
January 30th, 2010, 02:34 AM
OK what you need is double sided foam tape dont know in the US where to get some car paint factors sell it in the UK comes in differant widths or cheaper option draught excluder the thin foam stuff you put around doors DIY stores
Because its a Bass unit its going to vibrate something as im in the trade we hear more number plate screws rattle :lolflag:


ok, doubled sided foam tape ...where do i put it though ?

between the brake light and the window ?

or actaully in the trunk under the deck area ... thats what i would prefer, then you dont see any unsightly foam stuck to my window etc etc.

yeah i know it will rattle somewhat...but im doing what i can to stop as much of it - but theres a point where im just going to get it a bit better than it is now, and live with a few other rattles ya know ?

djmh
January 30th, 2010, 02:35 AM
ok, doubled sided foam tape ...where do i put it though ?

between the brake light and the window ?

or actaully in the trunk under the deck area ... thats what i would prefer, then you dont see any unsightly foam stuck to my window etc etc.

yeah i know it will rattle somewhat...but im doing what i can to stop as much of it - but theres a point where im just going to get it a bit better than it is now, and live with a few other rattles ya know ?


something like this ?

http://www.amazon.com/0451-Thick-Double-Acrylic-Adhesive/dp/B00136YHCW/ref=sr_1_7?ie=UTF8&s=industrial&qid=1264815261&sr=8-7

djmh
January 30th, 2010, 02:36 AM
Install "mute" and reboot.

sudo apt-get mute

gotcha...

wait... how the hell do i open terminal on my alpine ?

Kai69
January 30th, 2010, 02:39 AM
You could also use some sort of padding under the parcel shelf ive seen pillows being used because it damps the sound around the speaker ( not a joke) just duck tape the pillow to the shelf .

Kai69
January 30th, 2010, 02:44 AM
http://www.amazon.com/0451-Thick-Dou...4815261&sr=8-7 (http://www.amazon.com/0451-Thick-Double-Acrylic-Adhesive/dp/B00136YHCW/ref=sr_1_7?ie=UTF8&s=industrial&qid=1264815261&sr=8-7)


A bit thicker but yes thats the stuff put some around the 3rd brake light housing, In the UK theres no law to say you need a 3rd brake light so if its legal in your state just remove it .

sailthesea
January 30th, 2010, 02:51 AM
One more mini lecture then I'll get back to your problem;)
Being in a club with a 2KW sound system for a couple of hours is just as bad as being in a car with a 250W system or even listening to headphones really loud Its all about air pressure and peak dynamics One second of exposure to a really loud noise can deafen you, but the cumulative effect is the same over time.

Anyways I looked back at your posts to see what equipment you had
Your installer seemed to do a good job and gave you sound advice about about not thrashing Hell out of the sub;)

Getting the balance right is the key and check the thing is getting good air, a sub needs to "breathe", if you have it ported into the cab and the windows down a bit it sounds much better at lower volumes

sgosnell
January 30th, 2010, 03:05 AM
People who drive by with those enormous subwoofers blaring, and shake my walls and windows, really, really **** me off. What the **** is the point, anyway? I hope those fools all go completely deaf soon. And you sound just like one of those fools. If you're having the whole hatrack move from the subwoofer, you have things turned up way, way too high. Like a fool.
](*,)

Kai69
January 30th, 2010, 03:13 AM
We were all young once :guitar::guitar:

sgosnell
January 30th, 2010, 04:08 AM
Yes, but we don't all get old unless we're lucky. Getting old with hearing intact is a much better way to go, but then 'young and stupid' is redundant. :rolleyes:

steveneddy
January 30th, 2010, 04:09 AM
ok so my third brake light ..the whole panel its attached to actually, vibrates when my sub hits but the third brake light and defrosters are right on the rear window so it makes a terrible rattling..
its hard to describe ... right now i have some foam type material in between the third brake light and rear window (the legality of that is probably questionable lol)
but it does stop a good portion of the vibration, not all of it though, beacause the defrosters are uncovered (i like being able to see out my window) and it dosent hold the brake light entirly down ... so would you have any suggestion as far as getting rid of the rattling noise caused from the panel vibrating ?

im going to take a look in the trunk tommorow, and see if maybe i can bolt it down better ?

but if you have any experience or ideas i would appreciate it !!

i think dynamat and fatmat etc is a bit too expensive for me...but i also dont think it will solve my problem ?

open to any suggestions !!

thanks !!!

That's because large bass boxes in the trunk suck.

If you want great bass performance without announcing it to the world, have a professionally made box that is attached to the rear frame member that supports the rear seat. Seal the box to the cabin behind the rear seat.

Using this method you can use two 10's with less power and it would sound better in the cabin.

Pro's also mount little eight inch subs in small cabs under the seats firing up. This accomplishes the same thing, keeping the bass inside the vehicle, without ruining the interior trim due to vibration, not to mention the leaky trunk you will gain after months of overpowering bass.

I'm sure your neighbors would appreciate your attention to these details and your friends will be impressed that you have an awesome system that can't be seen when you open the trunk.

I have a 2002 Chevy pick up that had sound professionally installed right after I bought it new. The entire interior looks factory down to the custom covered subs behind the seat. I guarantee you that I have a better sounding system with better bass response that any "box in the trunk" rig I have ever seen.

The point:

Going to a pro may be slightly more expensive that buying "the box", but you will have a system that will simply sound better without ruining your hearing or the hearing of your passengers, not to mention the chics dig systems like I just described. Really.

The money you spend will be well spent. Get rid of "the box".

Kai69
January 30th, 2010, 04:12 AM
When one of these cars goes past something usually shakes lose and falls off you can laugh at that :lolflag:

djmh
January 30th, 2010, 04:22 AM
That's because large bass boxes in the trunk suck.

If you want great bass performance without announcing it to the world, have a professionally made box that is attached to the rear frame member that supports the rear seat. Seal the box to the cabin behind the rear seat.

Using this method you can use two 10's with less power and it would sound better in the cabin.

Pro's also mount little eight inch subs in small cabs under the seats firing up. This accomplishes the same thing, keeping the bass inside the vehicle, without ruining the interior trim due to vibration, not to mention the leaky trunk you will gain after months of overpowering bass.

I'm sure your neighbors would appreciate your attention to these details and your friends will be impressed that you have an awesome system that can't be seen when you open the trunk.

I have a 2002 Chevy pick up that had sound professionally installed right after I bought it new. The entire interior looks factory down to the custom covered subs behind the seat. I guarantee you that I have a better sounding system with better bass response that any "box in the trunk" rig I have ever seen.

The point:

Going to a pro may be slightly more expensive that buying "the box", but you will have a system that will simply sound better without ruining your hearing or the hearing of your passengers, not to mention the chics dig systems like I just described. Really.

The money you spend will be well spent. Get rid of "the box".

uhhhm, well i dont have a big box in the trunk ... i have no box ...

i had a proffesional install a ten inch 250 watt bazzoka bass tube..

as far as the pillow idea i think that is what im going to do !
i just need to find out how to detach the deck ...but that is probably the best way to stop the noise - thanks for the idea !!

Kai69
January 30th, 2010, 04:30 AM
Last time i asked the pros
alpine system with cd changer and speakers 1000.00
fitting and set up 3000.00
car 1000.00
I did it my self yes i had the interior out for a week but you couldnt see the speakers or the cables and it rocked
Now if I had a new car the price is would be ok

witeshark17
January 30th, 2010, 05:36 AM
I hope you solve the issue. Also, I suggest you turn it down whenever you use the rear de fogger to keep from cracking the back window.

steveneddy
January 30th, 2010, 06:41 AM
uhhhm, well i dont have a big box in the trunk ... i have no box ...

i had a proffesional install a ten inch 250 watt bazzoka bass tube..

as far as the pillow idea i think that is what im going to do !
i just need to find out how to detach the deck ...but that is probably the best way to stop the noise - thanks for the idea !!

Same thing as a big box. You will never get anything but car rattling noise out of that thing.

Most people don't seem to realize that the small space of an automobile cabin is no place for bass amplification and speakers that were designed for a space roughly 100 times the size of your car.

Case in point - my professionally built and set up home theater room is roughly a 20' x 20' room with a 15 foot ceiling. The subs in that room are two 8" speakers in one foot square ported boxes with speakers down firing and one 10" sub in a 14" square ported box, speaker down firing with a total of 350 watts RMS amplification for all three subs and it will rattle your bones.

The problem with tubes is they are set to one frequency due to the diameter and length of the tube. Tubes make the best bass when you start getting farther away from them.

Large theaters and sound environments will have at least three and sometimes up to twelve tubes of different lengths and diameters to handle the various frequencies produced by an array of various sized tubes.

If you only have one tube, it will have only one resonant frequency, and that's the frequency you will fight until you finally get rid of it.

Small 10's firing into the cabin from the rear with a sealing cabinet behind the speakers to contain the sound pressure levels and only two small 8's under the two front seats in small cabs firing up will add bass response that you can actually feel, which is the main component of the bass "experience".

What you feel actually makes you think that the bass is powerful.

Installing bass speakers in the manner that I describe will give yourself and your passengers the "feeling" that you have more power than you actually have.

Two 100 watt RMS amps should be enough to get that "feeling" with 2 10's and 2 8's in the car.

Point: the perception of loudness far outweighs actual loudness defined by sub frequency amplification.

Install one of these baby's:

http://www.thebuttkicker.com/car_audio/index.htm

and use the speakers for the upper bass frequencies and the buttkicker will handle what the ears can't hear.

*****************************

Of course, I know you aren't going to listen because you don't actually want good sound, you want to rattle the walls just like every other kid out there and you think that if you don't have a sub then you can't be cool.

Once you actually experience good quality professionally installed and tuned mobile sound, you will understand why boxes and tubes are so lame.

My .02

audiomick
January 30th, 2010, 03:04 PM
Hi.
I'll save the rant about exposing yourself to loud noise. I am also a professional sound engineer, and am more than aware of the danger, but it has already been said.

My personal opinion is actually that it is not possible in the appalling acoustics of a car interior to get really good sound, so I don't even start trying, but that is not the point here...;)

As far as your rattling goes, sticking things down is a good plan, the thing is, if they are stuck to something that is resonating, they will probably shake loose again. You might want to look into damping some things a bit.

What I mean, in principle, is this. If you have a large flat area supported only at the sides, it will resonate at some frequency, like a drum skin. If you add weight to it, the resonance frequency changes. If you add absorbers, it can't vibrate as much.

So, if you have, for instance, a panel above your boot that happens to go off at the resonance frequency of your sub or a multiple thereof (a sub speaker enclosure always has a resonance frequency. That's how they work. It means you get more out of a given quantity of energy) , it will rattle like mad when the sub is running, even if it is not that loud.

If you stick, for instance, a handful of small lead weights to the panel scattered around a bit, it will change the resonance frequency of the panel and (hopefully) stop it being excited by the sub.

If you stick high density foam to the panel, the foam will absorb some of the vibration and calm things down a bit.

As has already been pointed out, the sub needs an air path into the passenger space. That can be through cloth, seat upholstery and what have you, but if there is a sealed wall between the space that the sub is in and the passenger space, the energy has to go through the wall, i.e. the wall takes on the vibration from the air in the space where the sub is, and passes it on to the air in the passenger space. It must, in effect, behave like a second speaker diaphragm, i.e. it vibrates like mad.