Keep editting your post and I'll keep replying to the additions.
I explained already that below tuning the driver has to be protected with a high pass filter. That's the only proper way to use a ported box. If you don't use a high pass filter you will likely destroy the driver so you don't have to worry about distortion. BUT if you use the ported box properly there will be LESS distortion than a sealed box.
And you CONTINUE to talk about "fast". It's all just frequency response. Transient response has little to do with anything below 40 hz. Properly designed ports do not add distortion, for a given spl they lower distortion.
LOL, there's a girl here building a bicycle system and she actually knows what she's doing.
First she built the bike.
http://www.diyaudio.com/forums/subw...060-vs-3015lf-tapped-horn-52.html#post4702612
Then she built the sub. (30 hz tapped horn with some very nice pro drivers that will go VERY loud.) I don't have time to search for earlier posts with more info so this one should do.
http://www.diyaudio.com/forums/subw...060-vs-3015lf-tapped-horn-53.html#post4704150
Now she's going to be working on a synergy type horn for the rest of the frequency spectrum (synergy horns are state of the art and fairly new).
This girl's system is going to beat the pants off of anything you come up with in sealed boxes. In a head to head comparison you wouldn't be able to even hear your system over the sound this one will make.
And believe me, it will sound "fast" enough to please any audiophile in a blind test.
OMG i hate arguing with port lovers who refuse to do their homework, then snicker at ever piece of EVIDENCE you show them like the backwards apologists that they are. sure, maybe kicker isn't the last word in high end speakers, BUT they are speaker manufacturers and as such have to have an understanding of the science, especially in order to design speakers for specific applications.
when you KNOW your argument hasn't a leg to stand on, your ONLY option is to attack the validity of the science. for such alleged geniuses (my IQ's 157 along with being a logic based mastermind to boot BTW) your absolute refusal to accept science and instead argue from the emotional reptilian part of your brain (masterminds NEVER do that) and use schoolyard taunt strategies no matter how wrong you are.
i've read speaker design books from cover to cover, and they, like any CREDIBLE source acknowledge the distortions caused by ports all your "nyah nyah nyah nyah i'm not listening! i'm not listening" does to prove how stubbornly ignorant you CHOSE to be.
BTW... i was doing non mathmatical fluid dynamics calculations in my head at 3 years old when i told my grandfather that an inverted NASA duct would be the most aerodynamic hood scoop for his stock car, so i can very easily model a mass of air continuing inward motion after a cone stops moving until it crashes with the backwave.
SVS subwoofers preaching TRUTH
http://www.svsound.com/blogs/svs/75367747-sealed-vs-ported
Best for Critical Music Applications
A properly designed sealed subwoofer will typically exhibit less phase rotation, lower group delay, and reduced ringing in the time domain. These characteristics make the sealed subwoofer a natural choice for critical music applications, and are typically described by enthusiasts as sounding tighter and more articulate, with less perceived overhang.
but, according to all of you port loving geniuses, SPEAKER DESIGNERS kicker, eminence & SVS are all stoopid lying liars, and every speaker design book that acknowledges the same SCIENCE lies. that's your defense? really?
when you KNOW your argument hasn't a leg to stand on, your ONLY option is to attack the validity of the science. for such alleged geniuses (my IQ's 157 along with being a logic based mastermind to boot BTW) your absolute refusal to accept science and instead argue from the emotional reptilian part of your brain (masterminds NEVER do that) and use schoolyard taunt strategies no matter how wrong you are.
i've read speaker design books from cover to cover, and they, like any CREDIBLE source acknowledge the distortions caused by ports all your "nyah nyah nyah nyah i'm not listening! i'm not listening" does to prove how stubbornly ignorant you CHOSE to be.
BTW... i was doing non mathmatical fluid dynamics calculations in my head at 3 years old when i told my grandfather that an inverted NASA duct would be the most aerodynamic hood scoop for his stock car, so i can very easily model a mass of air continuing inward motion after a cone stops moving until it crashes with the backwave.
SVS subwoofers preaching TRUTH
http://www.svsound.com/blogs/svs/75367747-sealed-vs-ported
Best for Critical Music Applications
A properly designed sealed subwoofer will typically exhibit less phase rotation, lower group delay, and reduced ringing in the time domain. These characteristics make the sealed subwoofer a natural choice for critical music applications, and are typically described by enthusiasts as sounding tighter and more articulate, with less perceived overhang.
but, according to all of you port loving geniuses, SPEAKER DESIGNERS kicker, eminence & SVS are all stoopid lying liars, and every speaker design book that acknowledges the same SCIENCE lies. that's your defense? really?
Last edited:
from:
Sealed or ported: the differences in subs and enclosures
repeating the EXACT resonance analogy i made to dumb it down for all you truth haters
another LYING LIAR speaker manufacturer, whose scientists are stoopider than you:
https://www.mtx.com/library-vented-sealed-subwoofer-enclosures
all these speaker manufacturers agreeing with me... it's gotta be some kind of conspiracy. you just can't trust scientists. i could dig MORE evidence up in forums, but their credibility rating on this subject is absolutely zero with so many port lovers who just can't accept reality.
a scientist with an oscilloscope and everything! LOL
soundonsound... magazine for recording studio professionals (talk about sealed vs ported in several reviews, but this is what i found today looking for EVERY credible source i can find)
now where are YOUR CREDIBLE sources that prove your pointless point?
from:
https://www.mtx.com/library-vented-sealed-subwoofer-enclosures
all these speaker manufacturers agreeing with me... it's gotta be some kind of conspiracy. you just can't trust scientists. i could dig MORE evidence up in forums, but their credibility rating on this subject is absolutely zero with so many port lovers who just can't accept reality.
a scientist with an oscilloscope and everything! LOL
http://speakerdesignworks.com/Sealed_v_Vented_2.html
soundonsound... magazine for recording studio professionals (talk about sealed vs ported in several reviews, but this is what i found today looking for EVERY credible source i can find)
https://www.soundonsound.com/sos/jun04/articles/qa0604-6.htm
now where are YOUR CREDIBLE sources that prove your pointless point?
Last edited:
Bass Thump - can I offer one last bit of advice? And I mean this sincerely:
You may want to take a break from your speaker project and try to work on your anger / projection issues. Your reaction to the responses here has been disproportionately emotional to say the least. Life is way too short to be getting so torqued over things like this.
Take care,
-- Jim
You may want to take a break from your speaker project and try to work on your anger / projection issues. Your reaction to the responses here has been disproportionately emotional to say the least. Life is way too short to be getting so torqued over things like this.
Take care,
-- Jim
If you are a genius why are you asking for advice?
As I've told you, transient response, ringing stuff like that is basically inconsequential below 40 hz and if properly designed the port output won't be overwhelming so you won't even notice the fact that the lower notes are produced by a port.
Anyway, just for fun here's a sim of one of your chosen drivers in your 1.23 cubic foot sealed box. It's the Goldwood GW-1248. Your predicted qtc wasn't that far off, it's 1.92. But if you knew what you were doing you probably wouldn't consider a 1.92 qtc because this is what it looks like.
An externally hosted image should be here but it was not working when we last tested it.
That's at max spl, limited by the 3 mm xmax. It only takes 20 watts to hit xmax. F3 is right around 60 hz. This is exactly the type of thing that Kicker would be really proud of (the frequency response, not the sad sad low max spl).
I've been doing this long enough to know what the sim was going to show before I did it. And I have a pretty good idea of how it will sound. Do you? You may (or may not) be smart but if you don't study the subject matter this won't go well for you.
Distortion measurements and listening tests will show the way, I'm not going to do your homework for you.
It is true that the transient response of a sealed box will be cleaner and more accurate than a ported box. But it's inconsequential, it's not audible if designed properly. if you can tell the difference between a sealed box and a ported box IN A BLIND TEST with the same driver and same frequency response I'll eat my hat.
Besides, your opinions on this "science" posted by various manufacturers is a very small and simplistic part of the story. There's a lot more to it than you think. It seems that most of what you know came from manufacturer's websites and high end audio reviews. Believe me, that's not a good source of information.
Last edited:
i have no patience arguing FACTS with liars or the ignorant. i will fight to the death before yielding a millimeter to a lie.
when i DON'T know something, i'll admit it without hesitation. there's no shame in admitting you don't know something, but acting like you do when you don't? that's the kind of shame that demands rectification.
bottom line, you want to hate on sealed boxes, take your troll butt to another thread. there's a very good reason i chose sealed boxes... they're much lower distortion and i'm not going to let ANYONE come into MY HOUSE and start an argument about it, especially when they're WRONG!
you don't like hearing it? then take your troll butt the eff out of here and go hang out in the port lovers club. it's like freakin' invasion of the body snatchers where standing for the truth makes you an enemy. if you want to talk trash about sealed alignments, then talk about their lower output in the bottom octave. you'd be right and i COULDN'T argue with you on that, but it's the ONLY thing sealed boxes do wrong. as i've stated several times, i'm at peace with trading extension for sound quality. that's MY PRIORITY.
BTW, i'm not angry with YOU for your comment, whoever i quoted, but for everyone else who tried to play the gang up taunt and intimidate card. that crap doesn't work on me. ask my entire homeroom that decided they were going to gang up on me because i used to be an atheist. once one of them threatened me, i grabbed a pencil and was going to fight the entire room AFTER i fixed the instigator. i'm an antiphobic. when cornered, i attack, and have done so several other times i've been ganged up on. i won't accept it in a thread i created. this is my personal space and i refuse to be disrespected in it by fools who know not what they're talking about acting like ignorant schoolchildren trying to instigate a fight in a playground.
"heh heh heh... you like infinite baffle because you're an idiot pointdexter!"
"heh heh heh... get 'em billy! get 'em!"
Last edited:
You've proven beyond any shadow of a doubt that you don't have the knowledge base to determine the truth from "liars" and "ignorant".
While you have shown some truths here (like transient response being superior in sealed boxes) you clearly don't have the tools to rate the importance of that. It's inconsequential because it's inaudible in properly designed ported boxes. And it comes at the expense of inefficiency, distortion, high power requirements, and that brings on a host of other issues at high power. Power compression, even higher distortion, risk of driver failure.
I showed you a sim of what one of your driver choices would perform like. It's terrible. It doesn't meet any of your stated goals except the sealed box requirement.
But go ahead, waste your money. Don't be surprised when your "awe inspiring" system gets drowned out by a decent pair of bookshelf speakers on somebody's porch as you pedal your heavy inefficient whisper quiet sub past.
bass thump,
Let me give you some idea of what it takes to do 20Hz outdoors, with sealed boxes.
Take a look at this driver:
Beyma Speakers - Beyma 15P1200Nd speaker - Beyma 15P1200Nd lightweight neodymium woofer, 2400 watt 15" woofer for all bass applications. Beyma 15P1200Nd and other Beyma 15" speakers here at US Speaker.
It'll do around 15mm one-way travel before distorting much. I have four of them, and give each a solid kilowatt. Around 40L per driver, sealed.
Driven to amplifier clipping, 20Hz is just about audible, though there's definitely some distortion there, too. Simulations suggest around 115dB. If you stop at 40Hz, those same boxes can do 125dB, and that's the sort of SPL where the party starts.
Now, these are very very good drivers. Not the best in the world, but still very good. They won't go loud enough at 20Hz in sealed boxes for party use outdoors.
Looking at other kinds of resonant enclosures (not just ported, tapped horns are known for their low distortion), with a big tapped horn, and ONE driver, I simulate 124dB at 20Hz, and a block of four would really get interesting with 136dB at 20Hz. Same drivers, same power, 20dB difference at 20Hz.
You can argue all you like about distortion in the time domain. You want it loud, and big tapped horns will have 20dB (sounding four times as loud) more output than the same driver in a sealed box. That's like going from 1w to 100w, and the sealed boxes simply won't compete with that - the driver itself will be distorting really badly before it gets close to the performance of the tapped horn.
If you're sticking with sealed boxes because you prefer their time domain performance, that's fine. It really is. Something else will have to give, though - you'll be able to go loud at 60Hz, or quiet at 20Hz. Hoffman's Iron Law won't back down here: efficiency, low bass, small size - pick any two. You're currently trying to get all three, and I promise its not gonna happen.
I went for small sealed boxes because they're portable. I use relatively large amounts of power, and still come up against Hoffman - I usually aim to EQ the bottom end out for 35Hz extension, but sometimes that just isn't loud enough, so 45Hz or 50Hz will have to suffice.
Hope this has been informative. Just some real-world use of sealed boxes in an outdoors application.
Chris
Let me give you some idea of what it takes to do 20Hz outdoors, with sealed boxes.
Take a look at this driver:
Beyma Speakers - Beyma 15P1200Nd speaker - Beyma 15P1200Nd lightweight neodymium woofer, 2400 watt 15" woofer for all bass applications. Beyma 15P1200Nd and other Beyma 15" speakers here at US Speaker.
It'll do around 15mm one-way travel before distorting much. I have four of them, and give each a solid kilowatt. Around 40L per driver, sealed.
Driven to amplifier clipping, 20Hz is just about audible, though there's definitely some distortion there, too. Simulations suggest around 115dB. If you stop at 40Hz, those same boxes can do 125dB, and that's the sort of SPL where the party starts.
Now, these are very very good drivers. Not the best in the world, but still very good. They won't go loud enough at 20Hz in sealed boxes for party use outdoors.
Looking at other kinds of resonant enclosures (not just ported, tapped horns are known for their low distortion), with a big tapped horn, and ONE driver, I simulate 124dB at 20Hz, and a block of four would really get interesting with 136dB at 20Hz. Same drivers, same power, 20dB difference at 20Hz.
You can argue all you like about distortion in the time domain. You want it loud, and big tapped horns will have 20dB (sounding four times as loud) more output than the same driver in a sealed box. That's like going from 1w to 100w, and the sealed boxes simply won't compete with that - the driver itself will be distorting really badly before it gets close to the performance of the tapped horn.
If you're sticking with sealed boxes because you prefer their time domain performance, that's fine. It really is. Something else will have to give, though - you'll be able to go loud at 60Hz, or quiet at 20Hz. Hoffman's Iron Law won't back down here: efficiency, low bass, small size - pick any two. You're currently trying to get all three, and I promise its not gonna happen.
I went for small sealed boxes because they're portable. I use relatively large amounts of power, and still come up against Hoffman - I usually aim to EQ the bottom end out for 35Hz extension, but sometimes that just isn't loud enough, so 45Hz or 50Hz will have to suffice.
Hope this has been informative. Just some real-world use of sealed boxes in an outdoors application.
Chris
INCORRECT! i only used manufacturer websites because those were the most credible sources i could find online to repost, lest someone accuse me of lying which really frosts my nads. i learned about the superiority of acoustic suspension ORIGINALLY in my reading of every issue of audio magazine in the library from around 1984 until they went out of print, around 1987, i think. it was there i read about the likes of dunlavy audio, down to minimonitors like the "giant killing" $450 spica TC-50s along with acoustic research AR-3s and BBC rogers' LS3/5As and the infinity modulus 2 ways i used to lust after with their time aligned drivers and minimal diffraction causing baffles. the bigger brothers to the RS100s that instantly turned me into an audiophile.
that was where i started to learn the science WHY i liked the lightning fast bass out of 5 1/4 inch woofers as well as why the can't move as much air in the deep bass, but i really got into the science in the speaker design book that i used to own that introduced me to thiele small parameters. i've read many articles in stereophile, absolute sound, mix magazine, EQ, and online magazines since where the topic comes up from time to time.
as to the "best thump per watt", i figured it out myself using AJ sealed designer and applying it's response graphs to the printed, if accurate, response curves for the dayton and goldwood drivers and the results weren't even close.
the Goldwood GW-12PC-4 will do 69.5dB @ 20Hz in a sealed 1.23 cubic foot box., a full 3dB better than the next best, the Dayton Audio DCS305-4 which will do 66.5dB @ 20 Hz with everything else at 62.5dB to 65dB so thanks to whoever enlightened me to the availability of speaker alignment FREEWARE. the last i knew, you had to buy a $100 program to calculate output curves. with a nearly ideal QTC of .68, there should be very little underdamped booming and what bass there is in the bottom octaves should be plenty tight. using that driver will give me a full 3 to 7 dB leg up on other drivers plus the 6dB of gain from running 4 subs making my puny 150w sub amp sound like it's driving a single 12" with 1,200 or more watts. that's SHABBY for a BICYCLE SYSTEM? REALLY?
i also learned how to paste screenshots in windows paint and crop them from this.
Last edited:
This will be my first and last post here, because this thread is starting to resemble troll-spew.
60dB is about the level of a conversation in-house. Also, considering that our ears are less sensitive at low frequencies, for something to sound as loud at 20 Hz as a normal conversation, you'll have to add about ~50 dB, so that means almost 110dB at 20 Hz, to get it to "conversation level", i.e. the point it which you'll be able to hear it if someone's talking to you.
To add 3dB, you need to either (1) double the amplifier power (assuming your speaker can take it, or (2) double the amount of speakers. If you work out how many of those speakers or how much power you'll have to provide to get to 110dB @ 20 Hz, I'll bet that you'll end up with some very large figures.
(see Free hearing test on line – Equal loudness contours and audiometry for the "equal loudness contour")
An externally hosted image should be here but it was not working when we last tested it.
Goldwood GW-12PC
i'm fully aware of the 3dB rule as it both applies to doubling numbers of drivers and numbers of watts.
the whole "20 hertz audio doesn't exist" theory is absolutely BUNK! i could clearly hear my 87.5dB hifonics 12" subs driven by my 75w real world panasonic at 15hz in FREE AIR complete with phase cancellations and everything. that's why i had to go down to 8Hz tones to break the drivers in silently.
i swear this thread is troll bait for acoustic suspension haters who'll say ANYTHING to prevent someone from going sealed! of course there's a lowest octave compromise going the route i'm taking as i've said all along but all this "you'd be better off with a boombox" crap is ridiculous! i'm not trying to play to a stadium here, just cruise around with a CLEAN SOUNDING system that's reasonably full range.
20Hz DOES matter if one's trying to do an infrasonic demo like woofer cooker, but most importantly, it's a baseline to gauge response on every frequency on up. if a woofer destroys the competition by 3db or more at 20Hz, then it's going to be solid at 30Hz too. UGH! what's wrong with you people trying to start an argument about every mothereffing thing i effing say?!!!
it's MY EFFING SYSTEM, it will use sealed woofers, DEAL WITH IT, and i will be as happy as a clam with whatever CLEAN bass it delivers and the goldwood GW-12PCs will give me the most thump per watt without getting int0 $100+ subs.
be jealous that my bike system gets more play from the ladies than your 10,000w porsche. heh heh heh. people LOVE, especially the ladies, bicycle stereos! there'll be dancin' in the streets.
after that comes the LIGHT SHOW.
we're done here. y'all have been light on the help and heavy on the hindrance, though i DID stumble into what i needed to know to figure this out for myself.
Last edited:
- Status
- Not open for further replies.