 
|
Audio Asylum Thread Printer Get a view of an entire thread on one page |
For Sale Ads |
|
|
Audio Asylum Thread Printer Get a view of an entire thread on one page |
For Sale Ads |
67.87.195.207
I understand the 'basic' (measurable scientific) differences among the choices, my question is this: given the same 'basic' design, lets say an 8" or 10" 2-way.....which cabinet type do you prefer, and for what psycho-acoustic reason? My own observation is that a rear ported/vented box conveys a greater sense of 3D space, less in-the-box sound, and maybe tighter/better focus. I know there are a million variables, cabinet shape, design, crossover type etc....but I welcome your sweeping generic generalizations about which design you would approach from scratch.....I also subjectively observe that cabinet wall damping is a generally good thing with BR, but the effects on AS varies wildly according to amount, thickness, absorption etc.......
Edits: 09/09/16Follow Ups:
NOTHING thumps as fast as planar woofers! i don't care if they roll off. nothing sounds as fast and undistorted, especially on drums.
after that, i like smaller, generally faster drivers with nice acoustic suspension air springs. i'd heard many speakers in the 4 audio shops that used to occupy the boulevard in the 80s, but nothing impressed me like the demo my buddy gave of his $100 infinity 4 1/2" reference series minis with their foam surround poly woofers and 3/4" inch foam tweeters.
i couldn't believe just how TIGHT and UNCOLORED the bass was compared to larger ported bloat boxes. at no more than 4 feet apart too, they ran circles around everything i'd heard before in imaging. i had to read a few audio magazine articles to learn WHY i preferred the sound of acoustic suspension minis (which also made me come to the conclusion that anything else was an overpriced ripoff once you go sub/sat)
i just can't stand the bloated, sluggish, DISTORTED, boomy, phase & overhang challenged, often one note (as i like to call it... marshmallow bass) sound of ported speakers which DESPITE what their fans want to hear, and no matter how much EVIDENCE you present, even from SPEAKER MANUFACTURERS, are nothing more than distortion boxes that add resonances that DON'T EXIST in an original recording. my ears hate that. i will tolerate rolloff long before resonant bloat.
i just don't understand how ports are more popular other than the fact they sound bigger, but NOT better.
it sucks that so few manufacturers make sealed speakers anymore. speakers like NHT superzeros (they really need to make an air motion tweeter version with better woofers) punch way above their price point. a fact that speaker manufacturers probably don't want consumers to figure out, thus infinity and boston have sold out where they used to dominate as far as i'm concerned.
i was REALLY disappointed in my overpriced purchase of energy RC10 speakers i bought because of favorable reviews. they have EXCELLENT drivers, unlike NHT zeros, but also have larger LOUSY 5/8" MDF cabinets that induce UNBEARABLE box resonances once you plug the ports leaving owners the choice over what manner of distortion is more objectionable.
i think it's a conspiracy. it would be VERY EASY to manufacture a $500 pair of sealed minis that destroy speakers many times their price if someone used both high quality drivers AND cabinets.
i auditioned NHT $1000 classic 6 1/2" 3 ways which had tons of speed, detail and imaged like champs, but suffered from unbearable (low level, but noticeable enough for their price) aluminum signature driver distortions. UGH! they would have been giant killers with quality doped paper woofers, soft dome (even titanium) mids and air motion tweeters.
still, the SECOND audio revelation i had, was listening to a pair of maggie MG12s in a shop. i never liked planars because LARGER maggies sound like crap. the first pair i heard biased me against planars because they had an annoying distinct aluminum foil ping signature, but the smaller MG12s had no such issues and had an excellent totally resonance free open sound that especially impressed me with their bass speed that run circles around even 4 1/2" woofers for total mastertape sound.
since then, i've heard larger maggies twice, and again, hated THEIR shrill sound. i had to quit listening to my HQ japanese import dark side of the moon CD on them as i just couldn't take their brittle sound. it's possible that one of the reasons the MG12s sounded so much more liquid and relaxed was because they were driven by a really good CD player and a tube integrated for EXCELLENT system integration.
planars make the best subs. lightning fast... ZERO resonance and/or overhang and absolutely no box resonances. EVERY TIME, i'll take lack of distortion over extension. EVERY TIME... well... except for the 15" (but SEALED!!!) sub i'll be using for a bicycle trailer system where i have to move some air if i want to move some booties too.
I doubt even a 10 inch 2-way is going to manage 96db/w or better, even in a reflex box.A 10 inch 2-way infinite baffle is unlikely to be HE, unless you add a HE 15" bass driver to the baffle.
Speaker forum a better option, and a DIY site even better.
Warmest
Tim Bailey
Skeptical Measurer & Audio Scrounger
Edits: 09/10/16
I own woofers that were carefully designed to be used both as bass reflex and closed box. The closed box is definitely tighter and better controlled than the ported version.
However the ported version(which has a lower 3 dB down point does display a certain sense of more 3D space. Both the woofer designer, a friend, and I both agree on this and on what we hear. But the extra space is actually a distortion caused by longer overhang, longer settling time, for the ported box than the closed version. And the designer, of course, does know this. Interestingly though we agree on what's happening he likes the sound, the airy affect of the reflex version and I prefer the extra definition of the closed version.
dca140, your question is too tall an order to be reasonably handled in a forum like this. I suggest that you read a good loudspeaker Design and construction "how to" book then return here with more specific questions. I don't know what the best book of that sort is, but you could do worse than reading Vance Dickinson's "Loudspeaker Design Cookbook."
A true infinite baffle is not a portable device. There has been some confusion about what to call what. A sealed enclosure is just that, but it's not an infinite baffle. You already know what a bass reflex is, and there exists a never ending argument as to which is the best of the two.
I repeat, the argument will never end.
You're correct about infinite baffle, of course, but a closed box is called an 'infinite baffle' in audio and everyone knows that's what is meant, a closed box. What is often missed is that acoustic suspension is 'infinite baffle'.
How ever all closed boxes are not acoustic suspension. It's only acoustic suspension when the suspension of the woofer is so loose that the air in the sealed box is needed for control of the woofer, when the change in volume of the woofer's motion produces forces on the driver that they become a significant portion of the restoring force of the woofer.
To call any closed box an infinite baffle would be to assign an incorrect term. That is what I meant by saying there exists some confusion.
In an infinite baffle, there exists complete separation from the front and back waves of the driver PLUS the fact that there is so much air behind the driver, it has zero influence on the cone.
All sealed box systems have an effect on the driver because of the air behind the driver, in said box. Acoustic suspension devices impact a much greater degree of influence on the driver. It was once considered an acoustic suspension if the alpha factor was at 3, or greater. This definition has been lost over the years.
It is also generally accepted that vented systems, done correctly, are a better match towards higher efficiency. Sealed box proponents attack the vented box in very fashion as that of a political debate, that is, by citing some assumed and incorrect facts, and often times repeat and repeat these notions about "control, tautness and freedom from boom".
The fact is, a proper vented enclosure is difficult to execute, and is
very easy to screw up; hence the "bad press".
The older style large cabinets have a sound quality which can not be matched by puny little Mickey Mouse speaker systems.
A closed box inherently will exhibit less overhang than a reflex box. That's inherent in the physics of the design. A reflex can be quite good properly designed but not as good. There is no way a reflex speaker can be done to have as little bass overhang as a closed box.
Reflex was hard to design before computers but with a good piece of software and a knowledgeable designer it's not a big deal any more. I've seen it done. I've seen a whole reflex speaker done in half a day with only fine tuning (personal preference) left to do after computer design.
I have woofer boxes that were designed to be used both ways that were well designed by a very good designer and it's obvious that while the reflex design is among the best the closed box is tighter.
Well, if you think a sealed box is better, then by all means use one !!
What did I tell the original poster ?
The argument will NEVER end.
Of course the argument will never end especially in audio where everyone is an 'expert' which is true for his own use but that doesn't mean that in some situations there isn't a scientific answer. Extra over hang is not accurate. Liking it is another statement. My friend who designed my woofers prefers the affect of extra overhang probably because of weaknesses in recording but he does know it's distortion.By the way I do understand why my friend preferred the ported version of his woofer. I used it that way for a long time and it has alluring characteristics that I miss from the closed version. But that's taste and not fidelity to the signal.
Edits: 09/10/16 09/10/16
It's audio-folk-lore.
Vented systems actually have much less distortion than sealed systems.
See, I knew this would happen.
What is audio folklore? Why should reflex have less distortion? I need a measurement or better a logical reason. And isn't bass resonance(overhang) a distortion? And that's explainable and measureable.
What, you cannot actually read books to learn?
Buy "Bullock On Boxes" and study it.https://www.google.com/#q="bullock+on+boxes"
Warning, actual college level math is required.
Distortion goes up with excursion.
Reflex has much lower excursion than acoustic suspension (at the same SPL).
This only applies at and above tuning frequency (a woofer suitable for either use goes lower and louder in a bigger BR enclosure, with lower distortion).You might also want to look at horn enclosures, much harder to design and build but have even lower excursion.
Here's a man that does horns 'right':
http://www.prosoundweb.com/article/in_profile_tom_danley_exploring_the_possibilities_of_audio_technology/You'll get more respect if you actually research your own inquiries instead of arguing with people sharing their hard won experience.
FYI: I've built dozens of speakers from 1/4 to 25 cubic foot, I have built acoustic suspension, reflex and horn enclosures. I supported myself through the 80's doing live sound with cabinets I designed and built. Too hard on the body, I had to give it up before I caused my body to break down by moving a ton (literally) of gear several times a week.
It is really cool to see Tom Brennan and Freddy Ireson still posting here.
Jeff Robinson
Edits: 10/20/16 10/20/16 10/20/16
Audio-Folklore is comparable to when three blind men describe an elephant.
As to the operating principles of a bass reflex, or "vented loudspeaker",
I would encourage you to do your own research. I suppose I could easily answer your questions, but that would most likely result in continuing the "argument",
which is what I wanted to avoid in the first place.
Once a person has subscribed to an achieved belief system, evidence to the contrary would be considered invalid.
That's a trust me answer and worth nothing in a discussion. I do know something about low end design which is what my discussion is based on. The quality of closed box bass is better than reflex bass all things being equal. Reflex is used because it's what people are used to, it's more efficient and the drivers available unless custom made are designed to be used in reflex boxes and are not good matches with closed boxes.
Will you two please go get a room.
A closed box is not an infinite baffle. It's a mass-spring system.
And you cannot have a driver which is optimized for both bass reflex and closed box. The fact that one sounded tighter than the other can be attributed to several factors.
Of all the back-and-forth between you two, neither of you has shown even one single MLSSA graph, or gone any further than arguing about Merlot versus Cabernet.
I *get* that closed box doesn't do the "capacitor" thingy that bass reflex does, but the question is: In a well-designed system, can we hear it? If you cross a woofer at, for example, 100 Hz at 24 dB/octave, the "punch" and definition isn't even coming from the woofer. It's coming from the lower midrange driver.
Many years ago, I had the opportunity to learn from loudspeaker designer John Meyer (meyersound.com). He taught me a LOT about loudspeakers. Then, I read Olson's "Music, Physics and Engineering" and Dickason's "Loudspeaker Design Cookbook".
Other than from a purely theoretical perspective, a closed box is not necessarily better than a bass reflex box.
:)
I used vented boxes because the woofers I thought made the best midrange and most realistic vocals were woofers for vented boxes. Midrange trumps bass.
Now theoretically for a given driver size, output and F3 a vented design has less excursion than a sealed one and thus less harmonic and IM distortion. So with neither sealed or vented being perfect the choice of which makes better bass becomes a choice of what kind of distortion one finds more bothersome. A preference, a matter of taste.
In any event the proselytizing for sealed boxes on a HE forum puts me in mind of Jehovah Witnesses knocking on doors. "Don't answer the door, it's those sealed box people again!"
When the volume goes up those sealed boxes go up in distortion fast, easily hearable. That sound really bugs me, some folks might be more immune to it.
Post a Followup:
| FAQ |
Post a Message! |
Forgot Password? |
|
||||||||||||||
|
||||||||||||||
This post is made possible by the generous support of people like you and our sponsors:
Top of Page ]
[ Contact Us ]
[ Support/Wish List ]
[ Copyright © 2024, Audio Asylum, all rights reserved ]
