Vented Boxes Restrict Too Much Cone Movement

[nosaj070 10+ year member]

Math Class Time:

Alright 28 mm / 10 cm= 2.8 cm/2.54in=1.10236in of x-max

 

[bigbassman Premium Member]

making the enclosure larger will increase output... and increase excursion...

BUT..

you'll sacrifice bandwidth of play.. by increasing vb, you increase the peak above tuning.. which will limit the ability of the box above tuning...

I'll also mention that a woofer in a sealed box will not get to full excursion ability until you drop to 20hz and below..

to maintain a relatively flat response. the woofer has to displace 4 times as much air for each octave down in response..

therefore.. if you get full excursion from a woofer sealed @ 40hz... you break that woofer below that..

if you get full excursion from a driver at tuning in a ported box.. you break it above and below tuning..

you analogy saying that a woofer displacing twice as much air sealed due to excursion, will be louder than the ported box.. isn't correct..

in fact... I'll bet you money that if you build a sealed.. and have it tested v/s the ported on the meter.. the ported will be louder at ANY frequency between 25-50hz..

a sealed design only utilizes half the woofers radiating area.. the front waves from the cone.. other half of the output is in the box.. wasted..

ported systems utilize this rear wave, to radiate the mass of air in the port..

a ported design is more efficient then a sealed design.. its louder than a sealed design.. regardless of how far a woofer can throw..

if you still think a sealed is a better option.. build one.. test it v/s the ported.. one sub v/s one sub... sometimes the hard way teaches a lesson best..

Loyd L.

 

[WarDrumz 10+ year member]

my pee pee is bigger than dustins..
I win by default? //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

and yes.. a woofers excursion will be lowest, at, and just above the tuning frequency of the port.. however.. due to back emf, there will be an increase of excursion up to around one half to 3/4 octave above tuning.. the woofer will have the most excursion above tuning at that point..

and of course.. below tuning excursion increases until something breaks.. usually 1 octave or more below tuning frequency..

Loyd L.

BigBassMan, I don't understand the Octave stuff. So, approximately what frequency are you saying that my sub will reach it's longest excursion above tunning?

Thanx for your help man. I'm just PI$$ED off bcuz I know vented boxes can get louder than sealed boxes for 1. And 2, I know my sub can displace way more air than it is now if it could move further.

It's L O U D now, but if it could move 2" in that vented box, the sub's displacement + the vent would make me have a seizure, lol. I don't want it THAT loud daily, but just for certain occasions.

 

[WarDrumz 10+ year member]

Math Class Time:
Alright 28 mm / 10 cm= 2.8 cm/2.54in=1.10236in of x-max

That's nice how you broke it down, but what are you trying to tell me?

Yes, I knew that b4 you posted. I have the t/s sheet right beside me.

That is only HALF of my sub's xmax. 28mm is ONE WAY. So again, it could be moving twice what it is.

 

[ngsm13 5,000+ posts]

That's nice how you broke it down, but what are you trying to tell me?
Yes, I knew that b4 you posted. I have the t/s sheet right beside me.

That is only HALF of my sub's xmax. 28mm is ONE WAY. So again, it could be moving twice what it is.

Dumb ass. that's all i have to say...

oh, i'll add...the subs excursion is SUPPOSED to be minimal near tuning. Your SSF is supposed to be set lowr...1/2 octave lower like stated. ALSO, do you sit turned around all the time...just so u can watch the excursion while you are driving?? WTF...AND xmax is a number...and one way?? what's ur point?? Seriously...u need to educate urself...go join the 30 Below DUMB club. peace

NG

 

[helotaxi 5,000+ posts]

Given my circumstances, I believe that the sealed enclosure will give equal output. Twice the excursion will equal the sub at half the xcursion + the vent in my opinion.
PLUS, It will be easier on my amplifier and my electrical system because there is NO WAY I'll need the same 1500wrms in the proper sealed box to reach full xcursion. MAYBE 1000wrms, maybe.

I don't know exactly what your goals are, but more excursion equaling more output is really only true for the same enclosure. I can build a ported enclosure and a sealed enclosure for the same sub. Feeding them both the same power the ported will be louder from around 30-50 hz. This is without using a huge box or a high tuning trying to extract extra SPL from the ported box. Basically a SQ alignment. The excursion on the ported setup will be minimal around tuning. Feed the setup enough power to get the sealed system to reach its mechanical limits and the ported setup will still be louder and have less excursion. Just cause the sub has a ton of excursion doesn't mean you need or even want to use it all. If you are trying to listen to music the sub is more linear (read as accurate) in the middle of it suspension travel than at the ends. Just like having more power than you need is a good thing and bigger wire than you need is a good thing, more suspension travel than you need is a good thing.

 

[WarDrumz 10+ year member]

Dumb ass. that's all i have to say...
oh, i'll add...the subs excursion is SUPPOSED to be minimal near tuning. Your SSF is supposed to be set lowr...1/2 octave lower like stated. ALSO, do you sit turned around all the time...just so u can watch the excursion while you are driving?? WTF...AND xmax is a number...and one way?? what's ur point?? Seriously...u need to educate urself...go join the 30 Below DUMB club. peace

NG

FU(K You B1T(H. There is always someone to belittle another just bcuz he doesn't know as much. Why in the FU(K do you think I'm asking questions? Stupid A$$.

No I don't have the box turned around so I can watch it. I pop my trunk and set the gain listening for distortion, that's when I see how much it's moving, FAGG.

Since my sub is only moving 1", and it is designed to move 2", that means, OMG, it can move another inch. Meaning it is possible for my sub to displace more air, *******.

Your one of those internet "toughguys", talking big over the computer. If you said that to my face I'd break your FU(KIN back.

WEAK AS$ B1T(H

 

[davidfre21 5,000+ posts]

most ive seen loyd post ever... here

 

[WarDrumz 10+ year member]

I don't know exactly what your goals are, but more excursion equaling more output is really only true for the same enclosure. I can build a ported enclosure and a sealed enclosure for the same sub. Feeding them both the same power the ported will be louder from around 30-50 hz. This is without using a huge box or a high tuning trying to extract extra SPL from the ported box. Basically a SQ alignment. The excursion on the ported setup will be minimal around tuning. Feed the setup enough power to get the sealed system to reach its mechanical limits and the ported setup will still be louder and have less excursion. Just cause the sub has a ton of excursion doesn't mean you need or even want to use it all. If you are trying to listen to music the sub is more linear (read as accurate) in the middle of it suspension travel than at the ends. Just like having more power than you need is a good thing and bigger wire than you need is a good thing, more suspension travel than you need is a good thing.

Thanx man.

 

[WarDrumz 10+ year member]

Dumb ass. that's all i have to say...
oh, i'll add...the subs excursion is SUPPOSED to be minimal near tuning. Your SSF is supposed to be set lowr...1/2 octave lower like stated. ALSO, do you sit turned around all the time...just so u can watch the excursion while you are driving?? WTF...AND xmax is a number...and one way?? what's ur point?? Seriously...u need to educate urself...go join the 30 Below DUMB club. peace

NG

You talk BIG stuff over the computer. I bet your only 5 feet tall, with no hairline. Oops, my bad, that's your mother.

 

[packerfan 10+ year member]

You talk BIG stuff over the computer. I bet your only 5 feet tall, with no hairline. Oops, my bad, that's your mother.

Your the one talking **** over the net....contradicting asshat...go ahead, break my back, cuz you know what Im interested to see you try you numb skull. o0oo0 talking about peoples mothers...thats ****ing old idiot. So stop your fvuckin *****ing.

 

[havoc06 10+ year member]

yet another post, self destructed by the introduction of momma jokes...To sum it all up wardrumz, given you have built the ported box correctly, it will always be louder than a sealed box. Excursion really isnt the way to measure what you are looking for here.

 

[WarDrumz 10+ year member]

Your the one talking **** over the net....contradicting asshat...go ahead, break my back, cuz you know what Im interested to see you try you numb skull. o0oo0 talking about peoples mothers...thats ****ing old idiot. So stop your fvuckin *****ing.

I'm curious. Do you think it would've come to this if you would have kept your opinion of my car audio intelligence to yourself? Don't think so

 

[BooLeaN 10+ year member]

Ok you got your help, stop while you are ahead. More people you piss off, the less will want to help you out. Just remember, nobody here has to help you.

 

[WarDrumz 10+ year member]

Ok you got your help, stop while you are ahead. More people you piss off, the less will want to help you out. Just remember, nobody here has to help you.

Interesting you should say that. How exactly did he help me? By what... calling me a dumbass?

That really helps.

I see what your saying, but also understand where "I'm" coming from.