Yeah, was thinking about a ribbon tweeter, but only dome/horn/piezo available here bro...
OK, what's used in your stereo or what's available if planning one?
Sorry, mistaken...
Ah, the original design, but if you remember the modified P6BP posted here, it's a PVC ported (for smoother airflow), so I don't think it has to do something with horn-loading...?
Plus, reading many audio reviews, I gotta know 6BP (particularly the P6BP) seems to have a bad repute in group-delay (so that not recommended for hi-fi listening), and since my stereo will be two sealed cabs I guess it'd be noticeable, won't it be?
No mate, I'm gonna make a wholly new setup, okay, I'll tell you everything in detail, attached here is the living room under-construction, concrete floor and will be tiled, roof height is 10 feet, no ceiling yet, so 20*20*10=4000 cubic feet, a big room, bit complicated of a setup, most importantly there are no home audio professionals to hire in our country, we make all decisions by ourselves (which is very difficult since we aren't that knowledgeable), easiest is visiting a home audio showroom, buying a 1000W 5.1 (all-in-one including amp/receiver) for just 100 bucks, I know you won't be surprised, I'm not that silly, I'll make a custom or quit, that's why I'm here (and following many other forums as well)...
Update:
I heard you're a sound enthusiast and gained some popularity by the name "GM" in forums, may I know further about you?
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No, I described how to morph your dual vented chamber PBP6 to a long expanding tube folded back onto itself to load both sides of the driver.
True, but with such a low tuning combined with narrow BW it's moot due to our very poor hearing acuity [~65 dB down referenced to ~250 Hz where our hearing is getting pretty good], so the room completely dominates, hence where you want to concentrate damping since it's room Q that matters down low: Interactive Ear Sensitivity Chart - Independent Recording Network
Now if your 'sub' was usable/XO'd up this high, then yes, ideally need it very low.
True, but with such a low tuning combined with narrow BW it's moot due to our very poor hearing acuity [~65 dB down referenced to ~250 Hz where our hearing is getting pretty good], so the room completely dominates, hence where you want to concentrate damping since it's room Q that matters down low: Interactive Ear Sensitivity Chart - Independent Recording Network
Now if your 'sub' was usable/XO'd up this high, then yes, ideally need it very low.
Update:
I heard you're a sound enthusiast and gained some popularity by the name "GM" in forums, may I know further about you?
GM, GPM, altec, among others..........
You first since you can google me to find some stuff about me.
What??? Are TH and BP6 the same??? I'm feeling dizzy!!!
TH = BP6S or SBP6 = series tuned BP6 (pic 1).
PBP6 or BP6P = parallel tuned BP6 (pic 2).
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Okay, a bit of somewhat like the T-TQWT, but my design was a round ported P6BP of helmholtz resonance.
Well, since the "sub-bass" is generally between 20-60hz my plan is limiting the subwoofer to a narrow bandwidth so that it can optimally perform in that particular region, and looking for a design best within that 40hz range.
I know 6BPs would be the best as they're intrinsically short-band performers, but while agreeing to your "human ear sensitivity" statement, most audiophiles claim they can be "one-note wonders" and transients in them are mostly "suffering" (unless it's a QWP-turned P6BP like you suggested).
I know BP6S, but nick-naming it a TH might be misleading since TH is kind of a horn-loading and horn-loading mainly has 4 neck shapes as parabolic/conical/exponential/hyperbolic but this BP6S as illustrated has none of those, and even if you're referring to the uncommon 5th shape called "stepped" both resonators shown here are similar-sized in breadth, what am I missing...?
Correction: Your parallel BP6 = TH or T-TQWT = series [SBP6].
Yes in that the accepted most technically correct nomenclature is TQWT regardless of taper.
Well, if you listen to any true subwoofer with XO it will sound 'one note' regardless of box alignment and as Dr. Geddes noted it's the excited room modes that will determine how much 'one note' it is, so it's the proper integration with the mains that will determine how high an SQ it has as part of a full range system, which sadly is often a pretty poor one when a narrow BW sub system is used.
And if you can't accept this, then as he recommended, best overall to go sealed and use at least three to get sufficient power handling, good integration with the room and in any case, damp the room as much as practical; which yours being two rooms divisible by even integers it will 'ring like a ten penny nail struck with a ball-peen hammer', plus big enough for LF fundamentals to dominate the sub/woofer/lower mids BW all the way down to a ~1128/2/30 = ~19 Hz [notch/'suckout'], so don't envy you the amount of work ahead of you if you DIY with little/no help.
Re [multi] sub placement: http://www.wghwoodworking.com/audio/multsubs.pdf
Haste makes waste!
‘tH’ is just a false idea that reinforces the real idea. I dont ever understand why or how that doesnt or does make sense? in a sim it should become obvious? But it never does because nobody is thinking and simming what they think. Instead they just sim a slider that lands on a nice looking response curve resukt found and that barely means anything, especially that know body seems to be thinking or has in a long time??? Harry Olson long or longer? Martin king provided some definite ways to dilute things and get a result. A very nice one as well, just chamge the spring rate to a progressive one or sloped rate.... While neglecting to mention the ones he agreed with regardless (pipes are springs that work on parts of a fundamental spring and even damp themselves if organized within a pipe system suited to itself on either end of approach. and was too busy proving that he diluted the already proven he wasn't trying to disprove of even mentions much if at all.
The entire structure of a vent and a pipe is the only thing we are successfully doing. Horn is not a horn or even will be until we accept that its huge or its the waveguide on a tweeter? A horn is not a pipe and pipe physics are easy and simple and exist in everything in every way if you choose to try and look.
I have no clue why this is so simple, yet it is so very hard. The one way that it is crystal clear is also not at all perfect unless you make it. Paraflex is argue ably the mist profound way to look and see a pipe system and what will function if you really apply the ideas of pipe physics to speakers. Aif anyone doesmt look and doesnt make saw dust its a shame. Because its not that paraflex is anything or would be. Its what you gotta figure that makes paraflex so much mire than anything we mete mortals can use to have an ‘oh sh!t!) moment with our own curiously exploring experiments or questions when searching for how do things work’??
It might look like a lot of things, but make it what it is and youll see what i mean. I promise you it is not anything but it is anything you wanna create of you assume its a bundle of pipes that any pipe system would somehow do and does!!? Its not for anyone to judge or explain. It is for anyone to look and see. The problem with that is not pipe physics. Its the person who will or wont look throughout the pipes and use pipe physics!! The damn thing is real. And im nobody and i dont know nothing compared to most people around these places lwhos names we all recognize (GM is of course one of those names and continues to be. Hopefully never ever getting bored or loosing motivarion to do so) but paraflex could sure use a bit of GM polish or GM ideas to which a person could make a polishing compound for a pipe that takes out the swirls and leaves just a series of steps of perfect polished pipes joined from both sides of a tranducers cone.,, Silly horn thoughts are pipe dreams come true. Just ise pipe thought and it seems to be real? I promise, but im just a pipe smoking 4 strokin dork who tripped and fell into a broken leg or two and woke up in a speaker place where i could still goof around and create fun for myself
i think i foonfmd too much of a good thing, and a lot of them seem to exploit a common idea? Hint hint, wink, wink. Thats all i got, and i got nothing but other peoles ideas to claim or suggest that work, or that i learned from. If learning is fun, then paraflex and GM are a combo i recommend. If you research either (paraflex is a person btw) and put that info together youll see more than anyone who doesnt and if you dont not their fault, its because your not adding youre own ideas to the mix and thats when it all becomes amazingIf you take your idea. Study paraflex and look at many many things GM posts or links. Stick that in a book of basic air column(pipe phase physics included from any action or science of energy in
waves etc... you will see what you want to see and what your idea was surrounding. Its ironic that this type of stuff is a result of free will. Paraflex is based of a community of people who were previusly not bound by a dollar or an opinion of whats needed. And like GM the motivation was only to share and not to insist on anything except sharing in a community of common goals to which a real One might be found. Its not perfect, it never will be(?) i can make it perfect on a screen. but it makes it obvious what ‘perfect’ needs to be if you wanna see why its so very hard and yet strangely obvious. You cannot make perfect but you can surely exploit perfectly aimed intended things in no better way than one thatll shout it either good or bad or ugly! Its relentlessly honest. Use it or abuse it its fun!
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The paraflex will do everything GM stated (as per dr geddes) and infinitely worse if its allowed to. That is reality and it is exciting or frustrating or both to create and see yourself.
A paraflex indoors is twice the disaster the long part of a paraflex is if it was alone.
That is so not even close to how bad it sounds. But first realize im talking about a paraflex thats been misaligned and screams it is ! It is hideous but also hidden it very much seems, because i can fix it or create it in a moment and using any particular song it might be obvious and then not. So its by no mistake that a mistake fixed it.
And now is fixing anything...
A paraflex indoors is twice the disaster the long part of a paraflex is if it was alone.
That is so not even close to how bad it sounds. But first realize im talking about a paraflex thats been misaligned and screams it is ! It is hideous but also hidden it very much seems, because i can fix it or create it in a moment and using any particular song it might be obvious and then not. So its by no mistake that a mistake fixed it.
And now is fixing anything...
Well, mistakes happen, if you were to type "s" before "uck" but typed "f" instead (my experience), it makes a big difference...Haste makes waste!
That being said, I got confused once again by this...
As I could see, you're repeating "PBP6 = TH" here...?
I can (undeniably) accept it, low-passing @ 80hz (or even 100hz) isn't problematic for me, but won't that be more struggling for a ~ 20hz subwoofer to perform that far up (the only thing I'm worrying about)...?
I studied a lot about the sealed (not literally "acoustic suspension") enclosure which claims to have the perfect SQ in many aspects, but to achieve that ~ 20hz I'm looking for at a desirable SPL level, as you stated, my 4000 cubes (out of 5000 cubes) big square room would require four 18"s at least, so would be too costly (besides amp/speaker/wire commitment seems to be impractical cos I have to do all that by myself).
Just by a quick browse-through that PDF (thanks for posting!), I gotta know the optimal placement would be (though still room-dependant and me having an L-shaped room) two/four placing mid-wall, but that research done on sealed enclosures right?
‘tH’ is just a false idea that reinforces the real idea. I dont ever understand why or how that doesnt or does make sense? in a sim it should become obvious? But it never does because nobody is thinking and simming what they think. Instead they just sim a slider that lands on a nice looking response curve resukt found and that barely means anything, especially that know body seems to be thinking or has in a long time??? Harry Olson long or longer? Martin king provided some definite ways to dilute things and get a result. A very nice one as well, just chamge the spring rate to a progressive one or sloped rate.... While neglecting to mention the ones he agreed with regardless (pipes are springs that work on parts of a fundamental spring and even damp themselves if organized within a pipe system suited to itself on either end of approach. and was too busy proving that he diluted the already proven he wasn't trying to disprove of even mentions much if at all.
The entire structure of a vent and a pipe is the only thing we are successfully doing. Horn is not a horn or even will be until we accept that its huge or its the waveguide on a tweeter? A horn is not a pipe and pipe physics are easy and simple and exist in everything in every way if you choose to try and look.
I have no clue why this is so simple, yet it is so very hard. The one way that it is crystal clear is also not at all perfect unless you make it. Paraflex is argue ably the mist profound way to look and see a pipe system and what will function if you really apply the ideas of pipe physics to speakers. Aif anyone doesmt look and doesnt make saw dust its a shame. Because its not that paraflex is anything or would be. Its what you gotta figure that makes paraflex so much mire than anything we mete mortals can use to have an ‘oh sh!t!) moment with our own curiously exploring experiments or questions when searching for how do things work’??
It might look like a lot of things, but make it what it is and youll see what i mean. I promise you it is not anything but it is anything you wanna create of you assume its a bundle of pipes that any pipe system would somehow do and does!!? Its not for anyone to judge or explain. It is for anyone to look and see. The problem with that is not pipe physics. Its the person who will or wont look throughout the pipes and use pipe physics!! The damn thing is real. And im nobody and i dont know nothing compared to most people around these places lwhos names we all recognize (GM is of course one of those names and continues to be. Hopefully never ever getting bored or loosing motivarion to do so) but paraflex could sure use a bit of GM polish or GM ideas to which a person could make a polishing compound for a pipe that takes out the swirls and leaves just a series of steps of perfect polished pipes joined from both sides of a tranducers cone.,, Silly horn thoughts are pipe dreams come true. Just ise pipe thought and it seems to be real? I promise, but im just a pipe smoking 4 strokin dork who tripped and fell into a broken leg or two and woke up in a speaker place where i could still goof around and create fun for myself
If you take your idea. Study paraflex and look at many many things GM posts or links. Stick that in a book of basic air column(pipe phase physics included from any action or science of energy in
waves etc... you will see what you want to see and what your idea was surrounding. Its ironic that this type of stuff is a result of free will. Paraflex is based of a community of people who were previusly not bound by a dollar or an opinion of whats needed. And like GM the motivation was only to share and not to insist on anything except sharing in a community of common goals to which a real One might be found. Its not perfect, it never will be(?) i can make it perfect on a screen. but it makes it obvious what ‘perfect’ needs to be if you wanna see why its so very hard and yet strangely obvious. You cannot make perfect but you can surely exploit perfectly aimed intended things in no better way than one thatll shout it either good or bad or ugly! Its relentlessly honest. Use it or abuse it its fun!
Its because of the use of the TH function in HR. ANY enclosure modeled with that function is a BP6S.
The principles stay the same with new Paraflex function in HR. It's still a BP6S.
A Paraflex is a stepped TH that moves the mouth to the opposite end of a TH enclosure no matter if it's a single, double, or multiple fold enclosure. Just like a TH, a Paraflex can have a positive, straight, or negative flare.
Positive = SPL and big enclosure.
Straight = Easy build since the cross section area stays the same throughout the whole TH or Paraflex path. It's less efficient than a positive flare but more efficient than a negative flare.
Negative = low F3 and small enclosure.
The first 3 pics are the 3 different flared TH's.
Move the mouth or exit to the opposite end of the enclosure and you have pic 4, Paraflexes.
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Hmm, sounds good. But your mission, if you choose to accept it, is to sim a negative flared paraflex with a pair of dayton rss265ho4
its kinda funky to call a paraflex classic a ‘tapped horn’, its got a qw resonator in the ‘tapped’ entry to the mouth, no driver, and the seperate pipes formed are seen in the summed phase at exit and impedance plot as an 8 th order at times
Hmm, sounds good. But your mission, if you choose to accept it, is to sim a negative flared paraflex with a pair of dayton rss265ho4
When you split the pAraflex up as 80 cm in a 240 cm pipe 3 times and an
80 cm pipe off the polar opposite side output;(compound pipe). You can see how pressure phase in each of the 80 cm chunks is ‘90 degrees’ phase at the Fb pipe and 1/3 Fb ( in qw) pipe from 0 or meet at 160 as 180/-180 degrees(delay is weird in TH)... So Then 360 degrees at imaginery 320 cm combined pipe which can be observed as 160 cm(the fullcrum point between pipes and opportunity to fold as well as a csa change, etc. And thus 360(720) degrees all the way out from the full wave shape pressure node/antinode of 960cm. Or, the reality of 160 cm as the center frequency between pipes and 60’degrees in the location in an imaginery halfwave pressure phase sum so to speak? But using 0.5,1.0,1.5,1....2.0 pi is a lot better visual IMhO.
A horn doesnt do this, it cant. Only a pipe. Or a proper pipe step expansion used as described? the same 80 cm is seen if a person must use a 40 cm offset to place a second driver in the long frequency pipe. And also 120cm becomes viable to use in many ways in the long pipe. It too shuffles around the pressure phase between the pipes and their imaginery middle/fulcrum/node/antinode of harmonic shared.
A ‘perfect’ paraflex is in that or a similar use of the stepped pipe expansion. You cant have a negative flare or even a flare rate if you want perfect? It seems this is mother nature waving hello from the pipe maybe. See what you think?
Hmm, sounds good. But your mission, if you choose to accept it, is to sim a negative flared paraflex with a pair of dayton rss265ho4
When you split the pAraflex up as 80 cm in a 240 cm pipe 3 times and an
80 cm pipe off the polar opposite side output;(compound pipe). You can see how pressure phase in each of the 80 cm chunks is ‘90 degrees’ phase at the Fb pipe and 1/3 Fb ( in qw) pipe from 0 or meet at 160 as 180/-180 degrees(delay is weird in TH)... So Then 360 degrees at imaginery 320 cm combined pipe which can be observed as 160 cm(the fullcrum point between pipes and opportunity to fold as well as a csa change, etc. And thus 360(720) degrees all the way out from the full wave shape pressure node/antinode of 960cm. Or, the reality of 160 cm as the center frequency between pipes and 60’degrees in the location in an imaginery halfwave pressure phase sum so to speak? But using 0.5,1.0,1.5,1....2.0 pi is a lot better visual IMhO.
A horn doesnt do this, it cant. Only a pipe. Or a proper pipe step expansion used as described? the same 80 cm is seen if a person must use a 40 cm offset to place a second driver in the long frequency pipe. And also 120cm becomes viable to use in many ways in the long pipe. It too shuffles around the pressure phase between the pipes and their imaginery middle/fulcrum/node/antinode of harmonic shared.
A ‘perfect’ paraflex is in that or a similar use of the stepped pipe expansion. You cant have a negative flare or even a flare rate if you want perfect? It seems this is mother nature waving hello from the pipe maybe. See what you think?
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