Newbie Question: How to calculate Cu.ft Enclosure?

[Bert]

Should port for 33hz.. apparently its a discussion in the US forums as an article came out in Playboy that 33hz makes girls feel happy.....

 

[appleyard]

energie,
you not going to play at 30hz only, will ya? :)
like i said before, ported box will be louder across a band of sub-bass freq. in comparison to sealed.

on playing flat, it will depend on the subs and the box. Can't say it is sealed or ported. You can do Adire Audio Brahma in 4 cu.ft ported to 20hz and see how flat does it go. Not all ported box has a hump/peak if the 'sudden burst of bass' that you referred to.

i do understand with regards to port area and the power applied to it. You can reduce the power or don't oversize the port area and get away with port noise. Also you do not have to use big port area unless you really want to do SPL.
The example that i gave is only referring to the point brought up by Yong on why ppl use sealed box. His reasoning is coz' it is smaller than ported box. No mention of SQ or SPL here. And i assume you know the effect of using small sealed box, yep? So to really compare with ported box which is tuned low, you need to make the sealed box bigger.

I can't find T-S specs. for the RF HX2. If you do have, pls post. I try to strike a balance between port noise and its size.


cheers,
kip.
p/s: i do not use Peerless XLS by the way. I just pick up anything :D
my not updated site : http://www.sounddomain.com/memberpage/519352

 

[Yong_5290]

erm.myself is using a ported enclosure coz i'm into spl...

n 99% of those whom i meet in TT is using sealed..n their setup...SQ

 

[artnet]

Originally posted by energie@Feb 24 2005, 01:12
No dude, it won't " run away ". Matter of fact, it will get louder once you dump it in your trunk, that's cabin gain, which varies from one car to another, but you will definitely experience of a minimum of 3db rise.

:o
okie thanks!

 

[artnet]

Originally posted by Bert@Feb 24 2005, 09:08
Should port for 33hz.. apparently its a discussion in the US forums as an article came out in Playboy that 33hz makes girls feel happy.....

bert, wht if increase the 33hz? will help?? ehehehehe....

 

[appleyard]

Originally posted by Yong_5290@Feb 24 2005, 20:20
erm.myself is using a ported enclosure coz i'm into spl...

n 99% of those whom i meet in TT is using sealed..n their setup...SQ

Most ppl use sealed sub box for SQ coz' they want the bass not to kill others eg. the mids, the vocals etc.

Most ppl use ported sub box for SPL due to increased efficiency (+3dB at nearing port tuning freq.) and ability to tune the port high so that you have one note wonder which is loud.
But that does not mean you can't use ported sub box for SQ :)

Yong,
if you want to go loud, i suggest you learn how to use WinISD.
1. SPL needs big port area.
2. Needs big box for increased sub efficiency.
3. Play test tones to see what is your car resonance freq.
4. Then choose port tuning nearing your car resonance freq.
5. Must sound deadened the whole car.
6. Start to forget about 12" subs. You should go for 15".

 

[Bert]

neh... I was dreaming of getting a 18" RE XXX and mounitngit fre air using my whole boot as the box...

 

[appleyard]

bert,
i'm surprised that you still love SPL :D :P


cheers,
kip.

 

[Bert]

I always loved SPL... just it isnt practical for a daily driven car unless I want to get headaches everyday....

My next fun goal in 10 years is to buy an old car n convert it to a DIY purpose built SPL competition car... best is if I have sponsors and I will tune it for low bass SPL rather than 50-70hz SPL... imagine the looks on people's faces when the car burps a 160db at 35hz.. :)

 

[Yong_5290]

aplleyard...

i think i'll stick 2 12"
15" damn %$%$^%^& big 4 my boot....n i think 2 12" should be louder than a single 15" isn't?

is not tat i just wan it loud....in my opinion...theres 2 type of blasting...
1 4 ourself....
n the other 1 is to show ppl...

wat i wan is 2 char kei 4 myself...so wat i like is those hard bass...thump thump thump bass....mayb 70hz-100hz....

 

[appleyard]

yong,
two 12" subs will have more cone area than a single 15" sub. But if you get high excursion 15" sub, it will get louder. It is all about displacement and not just cone area. Try to imagine piston engine. The c.c is on the bore x stroke so you need more stroke rather than bigger bore only to increase the c.c
also 70hz - 100hz is tooooooo high. Usually the vehicle resonance freq. hoversaround 45hz - 60hz.


bert,
you won't get headache if you play loud at LOW freq. coz' its the car that vibrates rather than your head. Sounds nice too on some tracks which has bass sweep. It goes from shaking the car then your chest then your head :)
Feels like a jet going from behind to the front.

To get 160dB at 35hz is not easy tho'. Even Marshall-Joyner get less than 150dB with 3 15" Tempest with 1000W RMS (strapped Soundstream Rubicon). And he even get lesser number by swapping the Tempest with Brahma.


cheers,
Kip.

 

[Bert]

well.. cuz it isnt easy to do, thats y it would be nice to be able to come up with a car liek that...

 

[Yong_5290]

apple yard...i think 15" is good 4 playing low...which is not my type...of coz i know its loud...but mayb the area is small so mayb its slow?not like those 10" o 12" which i think is very nice 4 those drum n techno songs bass...thup thup thup...tis is wat i prefer....

i'm going 2 quit anyway...ahahhaa...so i'll just get 2 12" tats in my budget...just tat no to shiva....coz it looks ugly :P

 

[artnet]

Originally posted by Yong_5290@Feb 26 2005, 19:30
apple yard...i think 15" is good 4 playing low...which is not my type...of coz i know its loud...but mayb the area is small so mayb its slow?not like those 10" o 12" which i think is very nice 4 those drum n techno songs bass...thup thup thup...tis is wat i prefer....

i'm going 2 quit anyway...ahahhaa...so i'll just get 2 12" tats in my budget...just tat no to shiva....coz it looks ugly :P

darn, u call shiva ugly...
i think that is classic... that is so call precious...
ehehehe...

I love the look so much... whole thing dark. without logo will be best!
u open boot let others see... they might tot it is just a lousy paper cone
woofer... then u play it loud and precise... they will be amazed...

:D :lol: :D :lol: :D

 

[bullet_nos]

hey guys, wah, i read also i hin hin ar.
but i just wanna find out, if u all can help me out,

any good measurements for making a 1.65cft ported box? as in height, width, length...etc. and what if say that is the spec for one woofer, if 2 woofers, the cft x2? meaning 1.65+1.65=3.3cft? how to calculate correctly>? thanx guys. boy, if u guys r noob, im noobody. hehe
cheers

 

[appleyard]

you nned to know the TS parameter for the subs and how much power are you going to feed it.

you can do a box with 2 subs sharing it. yes 3.3 cu. ft / 2 so each subs will have 1.65 cu. ft.

 

[icecube]

Originally posted by artnet+Feb 26 2005, 19:52 -->

QUOTE (artnet @ Feb 26 2005, 19:52 )

--QuoteBegin-Yong_5290

@Feb 26 2005, 19:30 apple yard...i think 15" is good 4 playing low...which is not my type...of coz i know its loud...but mayb the area is small so mayb its slow?not like those 10" o 12" which i think is very nice 4 those drum n techno songs bass...thup thup thup...tis is wat i prefer.... i'm going 2 quit anyway...ahahhaa...so i'll just get 2 12" tats in my budget...just tat no to shiva....coz it looks ugly :P

darn, u call shiva ugly... i think that is classic... that is so call precious... ehehehe... I love the look so much... whole thing dark. without logo will be best! u open boot let others see... they might tot it is just a lousy paper cone woofer... then u play it loud and precise... they will be amazed... :D :lol: :D :lol: :D [/b][/quote] Ya, you are right... some of the best sub does look like a cheap paper cone sub... sometimes really doubt it can play tat well when u really blast it. Look at the bright side, theif also dont want to steal it .... kakakakaka :ph34r:

 

[Yong_5290]

hehehe...tats y i just mention it looks ugly...but perform vice versa...hehehee

 

[appleyard]

Most adire subs are plain simple. Why? because they invest lot of it into the XBL^2 motor. Thats how you got a great sub with a ridiculous price and some company invest a lot in cosmetic speakers what why you ended up buying some nice looking crap subs.

 

[bullet_nos]

what is TS parameter? and power i feed? er...say, maybe 200W RMS each sub?