Installing speakers

[RAd28]

Hey guys,

i've seen a few cases where people have enclosed speaker boxes for 6x9 speakers, i'm just wondering what the need is? and what the science behind the sizing is? and how do i find/calculate how big to make mine?

cheers

[EldarO]

basically, they put the correct volume of air behind the speaker, so that when you pump out music, as the cone goes forwards and backwards, the vaccum+ pressure will return it to the normal position quicker, hence upping response.

same principal in use with subbies.

Eldar.O.

[rob1]

You usually mount 6x9s in a box if you
1.don't want to cut your parcel shelf
2.can't fit them in the parcel shelf if you do cut it (maybe have the petrol tank under it)
3. Don't have a parcel shelf and no other reasonable means of mounting the speaker.

Eldaro is also right about having an enclosed space of air behind the speaker, but 6x9 boxes are really a last resort. I recently put some in a truck and they didn't sound to bad, but in a sedan I personally don't like the look of them in the back window.

[Lambolica]

If you box just about any speaker you will notice an increased response. That being said, most of the 6x9's that you see in a box are there for the resaons stated above. also to get a better angle of sound towards the front in some instances.

Personally I would only box them if I didn't want to cut the interior, or if the 6x9's were amplified. Or id I was going for good sound quality but if I was going for sound quality I wouldn't be using 6x9's anyway.

[Squid]

basically, they put the correct volume of air behind the speaker, so that when you pump out music, as the cone goes forwards and backwards, the vaccum+ pressure will return it to the normal position quicker, hence upping response.

same principal in use with subbies.

Eldar.O.

Surely as most 6*9's are 2/3 ways there is no seal from the cone anyways, making this less effective. I think it is mostly a location thing, a too lazy to mount them properly thing. I do Know someone who used them so he could shift speakers from car to car.

They are also a defect unless they are screwed down, it is equivelant to leaving a brick on the parcel shelf in the event of an accident.

[faulksy]

If you have a sub don't waste your time with 6x9's. get some 6's instead. and then only get those if absolutely necessary. if after sound quality you want your sound coming from infront of you, not behind. however 6x9's are a nice alternative where no sub present to give some bass

i have some 6's in my rear on very low volume not so i can hear but if i have people in the back assists the music not being drowned out by bass. if i didnt carry rear passengers i wouldnt waste my time. i get absolutely benefit from sound being staged behind me.

I know this is a bit off topic to your question but if after some good sound quality 6x9's will never be used in any application

caraudioaustralia.com is a very informant forum for questions like yours. has a very friendly community and will get great responses there

[45aken]

the whole idea of a box is so that it does not let the sound waves coming from the front of the speaker, be cancelled by the 180 degree out of phase waves coming from behind the speaker, and for suspension etc (said in previous posts) i would only suggest a set of 6x9's if you are not going to have a sub. they are designed for systems without subs (thats why they have the cone area of ~8" woofer) and for good sound and response, you relaay need to amp them.

[45aken]

oh and whatever you do, please do not just screw down the boxes into your parcel shelf. my mate just had a crash and he had a 12" sub (which was attached upside down in a box where the parcel shelf was) the box went all the way down to the boot floor, but when he crashed the sub ripped out of its 8 3" screws (16mm MDF), flew forward and smashed into the front window. missed his head by abour 3".
put em in the parcel shelf.

[RAd28]

thanks for all the responces guys...

basically what i really need to know is how to find what volume to make my boxes?
the reason i need boxes is simply 'cause i have nowhere to mount them... it's a RA28 after all... my plans were to make boxes, then mount them to the back of the rear seat so they sit just high enough to peer over the back, but not high enough to obstruct the rear view by much if at all...

If you have a sub don't waste your time with 6x9's. get some 6's instead. and then only get those if absolutely necessary. if after sound quality you want your sound coming from infront of you, not behind

i HATE when people say this (no offense to you)... you've obviously been spending considerable time listening to the guys from your local car sound shop? i have absolutly NO idea why these guys bother telling people this... because if that's the case answer me one simple question... why did they invent 5.1 surround if you get best sound with 2.1? forget a band stage senario, what about real life? do we have 2 speakers infront of us everywhere we go?
having said that, i understand exactly what your saying RE ditching 6x9's for the likes of 6.5" components and a sub.

the whole idea of a box is so that it does not let the sound waves coming from the front of the speaker, be cancelled by the 180 degree out of phase waves coming from behind the speaker,

ummmmmm sure...

[45aken]

anyways...
box size on 6x9's shouldnt matter, just make it the size to fit your application and keep it sealed. put some sound dampener in the box if it's small. rough sizes would be 13"Lx9"Wx6"D

[Draven]

best sound is 2.1? ok then, so why are all the best SQ car in the worls running 5.1(and lets try to see how many of these cars are running 6x9's), why do movies cinemas have 5.1 even 7.1? you said 'do we have 2 speakers infront of us wherever we go', where in actual fact the sound wherever we go come from all around us, not just left and right, and 5.1 can mimic this alot better than 2.1.

dude, that's exactly what he was trying to say - he was saying the "sound from in front" was a bad idea, and that 5.1 kicks the shit outta 2.1.
And he was also paying out 6x9 speakers, you're both on the same page with that argument

[RAd28]

lol....

you asked for science. it's not like i just did a whole 1/2 years work on the topic at uni or anything

6months?? that'd be 1 subject? a total of about 30-40 contact hrs?? you realise just how much you DON'T know? i've done probably a good year and a half, or there abouts, and still... i don't know half of the stuff out there...

if the sound waves from the back of the speaker would cancel out the waves from the front of the speaker... why do we not notice atleast a significant decrease in sound volume when we play a speaker free-to-air? and why would a box make ANY difference? sound waves travel faster in a solid object you know...

[45aken]

the box stops the sound waves getting out. and you notice a huge difference in the lower frequencies when a speaker is played free2air compared to a box. forget what i said about the 2.1 and 5.1 shit, i though you were sayin the complete opposite.
and im open to other peoples theory's, just voicing what i know.

[RAd28]

lower frequencies?? you mean like bass?

well that's got nothing to do with "stopping the waves getting out" it's all about resonance... if you make a box the correct shape and size, you create an environment which allows the speaker resonate at certain frequencies... basically it means you amplify the sound for free... this is what i wanna know... what size and shape will give me best sound?

[Lambolica]

Ok you have a situation there that I can see the requirement for a box...

for a volume of the box, around the 4-5 litre size will surfice but dont make it square (like a tissue box). either angle the top to fire the woofer forward or angle the mounting base.
You are probably better off putting them hard up against the tail gate and angling them up to fire at the rear window. Alternativly try and keep them away from the foldoing section of the seat (ie retain the full use of the folding rear seat) you may be able to bolt them to the rear quarter panels.
Another thourght could you put them in the rear speaker pods in the back seats angled up slightly. I have seen this done numerous times in RA28's

Cheers
Simon