ported or...

[phazeone 10+ year member]

hey brad farmer who are u to know about car audio buddy u cant even drive u yet so therefor how would u talk like u have any say in this what so ever

 

[ShaunMac 10+ year member]

Originally posted by phazeone hey brad farmer who are u to know about car audio buddy u cant even drive u yet so therefor how would u talk like u have any say in this what so ever

Because he's BRADLEY FARMER! //content.invisioncic.com/y282845/emoticons/cool.gif.3bcaf8f141236c00f8044d07150e34f7.gif

King of Brain Farts!

 

[more_spl 10+ year member]

"Cause He's BRRRRADDDD FFFFFFAAAARRMMERRRRR that's why"

When admins come in, can this guy be banned? For the good of the boarD?

 

[brad.farmer 10+ year member]

Just some general info for those people cracking on my lack of stereo expertise. Checkout what JL Audio has to say on the subject of speaker enclosures (http://www.jlaudio.com/tutorials/magic/performance.html).

"Sub-30Hz Behavior

Sealed box designs and single-reflex bandpasses are much better at controlling excursion at extremely low-frequencies (below 30Hz.) For this reason, they can usually handle more power in these frequency ranges than ported designs and dual-reflex bandpass designs which makes them less prone to low-frequency induced speaker damage. At frequencies below the tuning frequency of the port, a woofer in a ported box (or a dual-reflex bandpass) starts to de-couple. This means that the controlling function of the enclosure begins to disappear. The collapse is gradual rather than immediate, but at some point below the tuning of the port, the speaker behaves as if it were operating without an enclosure and suffers from potentially damaging over-excursion. (This is why it is a good practice to use a sub-sonic filter when running a ported enclosure or a dual-reflex bandpass. Some high-quality electronic crossovers like the AudioControl 4XS incorporate a programmable subsonic filter circuit.) "

The point that I was trying to get across is that typically, although there are exceptions, sealed enclosures will play lower than ported enclosures. This is due to the fact that in ported enclosures the sub appears to be operating in an infinite baffle at frequencies significantly below the ported frequency. Can you build a ported enclosure that goes extremely low (10-20Hz) region. Yes. ALthough it takes a ton of box volume and a long port.

On the subject of bandpass enclosures. They sound like "crap" if you don't know how to build one. Building high quality bandpass enclosures is very complicated and should be undertaken utilizing enclosure design software (LEAP or something similar). When it comes to using high excursion subs in bandpass enclosures things can get very squirrelly.

brad.farmer

 

[brad.farmer 10+ year member]

Originally posted by dave_3148 brad the usual diffrence between sealed and ported is 3 db wich is easily noticable

The difference is 3 db at the ported frequency. Not across the entire response curve for the woofer.

 

[dave_3148 10+ year member]

didnt you say the other day "jl and kicker are crap" if there so bad why are you taking advice from them

 

[tommyk90 5,000+ posts]

Well, you can take JL's word for it, or you can actually LISTEN to two comperable setups (one sealed, one ported) and then base your judgements. You can say all the stuff in the world but it doesn't mean shit if you don't have evidence to back it up. I'm sticking to my original statement that ported boxes hit deeper because every ported setup i've heard have hit lower than sealed ones. The reason behind my opinion is that in a ported box the subwoofer can move more freely and can get more excursion on those low notes. I don't know if that's the right reason, but that's where i base my judgement on.

 

[brad.farmer 10+ year member]

Originally posted by dave_3148 didnt you say the other day "jl and kicker are crap" if there so bad why are you taking advice from them

Look guys, there are several other sources that I could easily refer to. Instead of bashing me on the internet, why not take some time and read up on theile small enclosure design. I welcome intelligent conversation... However, I'm having trouble finding it.

brad.farmer

 

[dave_3148 10+ year member]

no one wants to have a "intelligent conversastion" with someone who says dumbshit. you've argued with just about everyone on this board and got proved wrong so apoligize or leave.

 

[brad.farmer 10+ year member]

Originally posted by tommyk90 Well, you can take JL's word for it, or you can actually LISTEN to two comperable setups (one sealed, one ported) and then base your judgements. You can say all the stuff in the world but it doesn't mean shit if you don't have evidence to back it up. I'm sticking to my original statement that ported boxes hit deeper because every ported setup i've heard have hit lower than sealed ones. The reason behind my opinion is that in a ported box the subwoofer can move more freely and can get more excursion on those low notes. I don't know if that's the right reason, but that's where i base my judgement on.

I have listened to comparable setups: sealed, isobaric, single reflex bandpass, dual reflex bandpass, ported, transmission line, and horn. Yes, I'm fourteen years old and I've listened to all this stuff. When your father was a car stereo installer and is an electrical engineer with ten years audio/video/computer system design experience (and still an avid car stereo fanatic with a 2KW system). His designs include system designs in the Pentagon... you get to hear lots of different systems. NOW SHOULD I BASE MY RESPONSES ON INFORMATION FROM SOMEONE WHO HAS TO RESORT TO CURSING TO MAKE HIS POINT or SHOULD I BASE IT ON MY OWN VERY VERY DIVERSE EXPERIENCE. I think that I'll go with what I know. Peace Out, Loser.

brad.farmer

 

[tommyk90 5,000+ posts]

Originally posted by brad.farmer I have listened to comparable setups: sealed, isobaric, single reflex bandpass, dual reflex bandpass, ported, transmission line, and horn. Yes, I'm fourteen years old and I've listened to all this stuff. When your father was a car stereo installer and is an electrical engineer with ten years audio/video/computer system design experience (and still an avid car stereo fanatic with a 2KW system). His designs include system designs in the Pentagon... you get to hear lots of different systems. NOW SHOULD I BASE MY RESPONSES ON INFORMATION FROM SOMEONE WHO HAS TO RESORT TO CURSING TO MAKE HIS POINT or SHOULD I BASE IT ON MY OWN VERY VERY DIVERSE EXPERIENCE. I think that I'll go with what I know. Peace Out, Loser.

 

brad.farmer

F*ck you man. I base my opinions on what I'VE heard, not on some little teenie-bopper who's got his head stuck up his ***. I feel that ported boxes hit deeper, that's my opinion. You don't have to come back at me with some technical jargon that nobody gives two shits about. I feel it hits deeper, many people on this board with more experience with you (yes it is possible to know more than brad farmer) think it hits deeper, so you know what, you can either agree or disagree. And if you disagree that's fine with me. Just don't argue with everyone here on why since you think sealed is louder than everyone should too cause nobody will listen to you. Peace out, f*cking douche-bag.

 

[dave_3148 10+ year member]

u think you have all this experience, jlaine and some of the other youve dissed have more years experince then you have been alive. so dont try to act smart when your wrong just omit your wrong and say sorry.

 

[Randy Savage 5,000+ posts]

Brad, while what you took from JL's site is correct, you failed to realize that it depends on tuning. A box tuned low (low 30's- mid 20's), will have better low end response than a sealed box.

Once again, here it is-

A sealed enclosure will be the smallest (for a given response shape) and will have good low frequency extension but may not have the best low frequency extension. If space is limited, this may be your best choice.
A ported enclosure will generally have a better low frequency extension for a given response shape (alignment) but would require a larger enclosure. If you made the enclosure as small as the sealed enclosure but ported it to gain the low frequency response, the output would deviate from the desired flat response.

 

[bass_mekanik 10+ year member]

that is brad farmer and what you all said is correct from my experience a ported box will sound deeper but on paper it will be a different story to prove this point get 2 subs one sealed and one ported to a "normal" tuning freq that is around 35-45 hz listen to both with some deep *** tones like 20 hz is good tell me which one sounds loudest when playing deeper and alsop which one handles the deep bass better sealed gets the besp results...

the apparent deep bass that a ported enclosuer has is from the peak they normaly have around the 40-60hz range whick is where most of the bass in normal music is and also where we hear bass frequencys best..

that concludes my rant and also negates any need for yall to argue with that little F@G brad just cause his daddy is a car stereo tech dood don't mean that little ***** knows F*CK all so go back to your daddy and stick your head in his *** where it belongs

 

[Wonderbread 5,000+ posts]

Brad, you are wrong... and here is why...

In a sealed box, very low frequency output is minimal. the f3 (-3 db down point) is usually fairly high (above 30 hz in most cases). the only way to lower this f3 spec is by DECREASING the Qtc. of the enclosure - making it vastly larger than Butterworth configuration. Sealed boxes are also, by nature, less efficient.

Vented (bass reflex) boxes can have their f3 point near or even below 20hz. Basically, they get louder, lower. plus, they are more efficient, about 3db more efficient.