Is there a reasonable effort (maybe even successfully repeated ) which folds the segments of any qw path in a way that creates intervals of the fundamental which are useful? Standing waves as shown (sort of) in the drawing the green pattern doesn’t necessarily peak and valleys much with the blue(fundamental tuning example), but the orange matches up half of the time it’s at its higher frequency. even if this was ‘over welming’ it would be interesting. I had a link to share where some guys in Sweden did something similar, but I think I might have thrown a wrench in that sprocket with the bottom chamber (labeled absorber) and the tapped output after the initial Blue section (200cm2 @ 215-235cm). Too much going on here. It sims well in a variety of ways (with adjustments here/there..
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What you drew in your pic is the velocity of the 5th,10th and 15th resonant frequencies, the 10th cannot exist though.
We want only the fundamental, which has 0 velocity at the closed end and maximum at the open end.
The stubs are not efficient at the closed end, they need to start at points of max velocity, which is 1/3, 1/5 ... away from the closed end.
At points of max pressure you can only use Helmholtz resonators
We want only the fundamental, which has 0 velocity at the closed end and maximum at the open end.
The stubs are not efficient at the closed end, they need to start at points of max velocity, which is 1/3, 1/5 ... away from the closed end.
At points of max pressure you can only use Helmholtz resonators
You wanna dig a rabbit hole with me?😀 i promise you can leave at any moment before we reach the water table and drown!
Heres a bit of more beautiful disaster.. plan B? But there's a C too...
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Kinda stuck with the first long qw pipe (switchback)section. But the entire ‘tapped mouth and out can be anything at this point(sawzall modifications included)? Anything!
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So whats going on in these that i can hear that wasnt before? higher frequencues? I git things buzzing and jingling that werent in straight TLs previously used?
Is there a seperate set of harmonics in the ROAR or Parafkex (or maybe just paraflex as its compounded higher order cabinets? In addition to the ones typically in other cabinets? Created by the substantial presence of the other chambers output?
Is there a seperate set of harmonics in the ROAR or Parafkex (or maybe just paraflex as its compounded higher order cabinets? In addition to the ones typically in other cabinets? Created by the substantial presence of the other chambers output?
To break up a fundamental into multiple smaller ones requires an impedance mismatch at each point with one way [used in a popular BLH] is to taper a section and inverse taper the next one, etc., for however many segments desired.
GM
I trieded a qw version of double BR...or the opposite actually, amidst a tapped driver. basically offsetting the second chamber though.. funky but pollyfill shows a lot of promise here?
Hmm, we have three acoustic filters to play with, high pass, low pass and offset or not, this is a band-pass filter: http://users.cms.caltech.edu/~ps/All.pdf
As for the funky QW, seems like DSL's DTS TH series is the TH per the symbol dwg., but too tired to figure out what the rest of it's for.
Regardless, we can only trade efficiency for BW and vice versa, so calc a driver's extremes to guide you or vice versa like pros do.
On another note 😉, B0$3 has done a lot of research, so browsing old patents may help, but the best of course are the newer ones that only certain folks can access.
When I first glanced at your symbol dwg., their Wave Cannon patent came to mind and pretty popular around here till the TH took off. Never seen so much confusion over such a simple tapped pipe till finally posted a complete [to the point of confusion for some] design routine and the late DJK pointed out it could be 'bent' to be an acoustic half square wave antenna [later found out it's in one their patents, though not described as such], filling in the 3rd harmonic dip like DSL does with its DTS THs: https://www.diyaudio.com/forums/subwoofers/9501-acoustic-wave-canon-6.html#post1175482
GM
The fountain of knowlege or directions to get it, thank you Greg! Excellent reads🙂
I need to make my large chamber ‘adjustable’ ... i think ive gotten close quite a few times, but its always a bit akward or creates it in the ‘room’...
I need to make my large chamber ‘adjustable’ ... i think ive gotten close quite a few times, but its always a bit akward or creates it in the ‘room’...
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You can use google translate for this thread in Swedish Hififorum. Member Asto compares straight quarter wave pipe to pipes folded one and two times. HiFiForum.nu - Spelglädje under 1000 Hz
The Psyche As Interaction
Strange this harmonic thing and frequencies we can ‘fold’ into standing waves of each segment?
Strange this harmonic thing and frequencies we can ‘fold’ into standing waves of each segment?
Fs38.5
Sd 506.7
Re3.9
Le4.2
Vas22.3
Qes.35
Qms5.15
Xmax15
A qw subwoofer for this driver thats folded in its own fundamental frequencies intervals, or even as chambers of the same ! Ive come close, but i think theres more to it...?
Sd 506.7
Re3.9
Le4.2
Vas22.3
Qes.35
Qms5.15
Xmax15
A qw subwoofer for this driver thats folded in its own fundamental frequencies intervals, or even as chambers of the same ! Ive come close, but i think theres more to it...?
The pipe will always have a velocity maximum at the end since the opening should have the same pressure as the surrounding room.
At the fundameltal you will have a pressure maximum at the closed end.
When the frequency increases the pressure node will "walk" towards the open end. When the pressure node finds a corner, the corner will "help" the standing wave.
At the fundameltal you will have a pressure maximum at the closed end.
When the frequency increases the pressure node will "walk" towards the open end. When the pressure node finds a corner, the corner will "help" the standing wave.
This conundrum we can skew? Or make ‘best’ by how we layout the folds
Maybe it can be seen when looking at the taper or expansion shapes affect and resulting tuning hz?
I usually get mote confusing then i can describe trying not to... but i have been chasing something. And its akward but ive been ‘off’ slightly (and it shows, at various frequencies, as you said) it sounds weird, then great, then weird... repeat... and ive sharpened it more and more. But not correctly or still i am ‘off’ the mark?
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