I have not built an extension, yet..
I was hoping to find some time and fiddle with different mods that can be done on a finished box to extend the useful range so I can persuade my brain to let it go.
Because I t’s purely an intellectual problem with me using a 8” coaxial to my tham15.
They sound amazing even with lower crossover than I would like.
But nothing built yet.
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But it has been done. But I have no idea of the result.
I was hoping to find some time and fiddle with different mods that can be done on a finished box to extend the useful range so I can persuade my brain to let it go.
Because I t’s purely an intellectual problem with me using a 8” coaxial to my tham15.
They sound amazing even with lower crossover than I would like.
But nothing built yet.
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But it has been done. But I have no idea of the result.
When the time comes you might find it difficult. there’s so many options and good things to decide and directions or shapes to use... add a small absorber to it and fabrication constipation is suddenly to much good stuff to choose! Out come the heavy duty drawer slides and Collapsing brackets for a variety of extensions. good luck, it’s kicking my ***
. I wish this stuff had a bigger following or interested more people it’s kind of a desert more than oasis of ideas to approach are part of the curiousity
and a bigger enclosure THAM (with longer horn inside) is a SUB enclosure too. roar is 2.5x bigger than THAM.
Remember: tham 12" 96 liters, roar 12" 230 liters.
Remember: Hoffman’s Iron Laws of Speaker Building
1) Bass Extension
2) Efficiency
3) Small Enclosure... pick 2
THAM have Efficiency and Small Enclosure, and no low Bass Extension.
ROAR is more with Bass Extension and Efficiency, but with a little bigger Enclosure.
So, THAM is 2) + 3) and ROAR is 1) + 2)
True?
Remember: tham 12" 96 liters, roar 12" 230 liters.
Remember: Hoffman’s Iron Laws of Speaker Building
1) Bass Extension
2) Efficiency
3) Small Enclosure... pick 2
THAM have Efficiency and Small Enclosure, and no low Bass Extension.
ROAR is more with Bass Extension and Efficiency, but with a little bigger Enclosure.
So, THAM is 2) + 3) and ROAR is 1) + 2)
True?
then you don't need efficiency or small enclosure. I will go (for home @ 30Hz) with some long excursion ... huge enclosure...
maybe some TH112 | Danley Sound Labs, Inc.
maybe some TH112 | Danley Sound Labs, Inc.
wait, he said 45-50 in car audio and that’s a wrap!
tapped horn is too, but now 30 in a house...
Does that really mean 30? From one car audio AND any audio user of qw type cabinets or intended until 20 hz.. do you say 30 but wanna say 20 if honest? Cause I think we understand the same issue and why you car reference is why I think you might say 20 if it was easy or okay to get it?
if so, I’m on the hunt too, but maybe we both have ideas that can collide into a solution? I’m playing fair, and using very little $$ except for wood and materials hopefully. Covid, etc? Who knows, but wood is still cheap and it’s therapuetic to stay focused away from the worlds human confusion and worries... Life was fine before and maybe after, meanwhile subwoofer?
Ever consider a car audio friendly version of the BP4 concept? I don’t know if it’s a version of ROAR, but I have an idea? The dual opposes creates something by loading upstream on a way you gotta curve into the sim. fake the pinchpoint in the drawing . this can show something if repeated. Use the green as a huge leaky cabinet (car) but now you’re inside the green area too? Mass load it at and what happens? well then pretend that’s gonna happen is a car too....it trickles dune. But it’s standing waves of higher up stuck in folding. Not strategic folding maybe? Even with the wide open big mouth? if folded into ways that support bandwidth and also don’t getvout if they don’t. I have crazy issues with tambourines that no MLTL ever caused. I think I’m figuring out what and why? But I’m a newbie and leapfrogged into a pitfall(qw highr orders) I’m flying blind and the learning curve is steep but sloppy..
tapped horn is too, but now 30 in a house...
Does that really mean 30? From one car audio AND any audio user of qw type cabinets or intended until 20 hz.. do you say 30 but wanna say 20 if honest? Cause I think we understand the same issue and why you car reference is why I think you might say 20 if it was easy or okay to get it?
if so, I’m on the hunt too, but maybe we both have ideas that can collide into a solution? I’m playing fair, and using very little $$ except for wood and materials hopefully. Covid, etc? Who knows, but wood is still cheap and it’s therapuetic to stay focused away from the worlds human confusion and worries... Life was fine before and maybe after, meanwhile subwoofer?
Ever consider a car audio friendly version of the BP4 concept? I don’t know if it’s a version of ROAR, but I have an idea? The dual opposes creates something by loading upstream on a way you gotta curve into the sim. fake the pinchpoint in the drawing . this can show something if repeated. Use the green as a huge leaky cabinet (car) but now you’re inside the green area too? Mass load it at and what happens? well then pretend that’s gonna happen is a car too....it trickles dune. But it’s standing waves of higher up stuck in folding. Not strategic folding maybe? Even with the wide open big mouth? if folded into ways that support bandwidth and also don’t getvout if they don’t. I have crazy issues with tambourines that no MLTL ever caused. I think I’m figuring out what and why? But I’m a newbie and leapfrogged into a pitfall(qw highr orders) I’m flying blind and the learning curve is steep but sloppy..
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Below the tuning frequency of a BP4, the enclosure acts like a sealed enclosure. If you know anything about transfer function, then you SHOULD know a sealed enclosure only needs a F3 around 45-50hz ground plane (2Pi).
I would NEVER have ANY type of BR or BP6 SUBwoofer enclosure in MY car or home with a tuning of 45-50hz. MY BR/BP6 would require 30hz or below due to unloading below Fb.
Even a closed back with dual front chamber which is somewhat, a 6th order ?
hence the question for home use? and not even a hint of the car audio vs anything but sealed from me... i bring a ballistic missle to that knife fight and still it wont win. but its not necesarily how i feel 90%, and that 10% isnt a sealed or sealed with a shaped surrounded output of sorts. but its not right...
house. after car is often tainted with the feelings of that car transfer addiction and hard to break the habit or thought process. guess not in your case and i SHOULD not assume anything. but still i have to put myself in check or the house i might wreck.
but a coffee table and the car share some things... sometimes.
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High tuned quarter wave designs does not drop of as fast as normal bass reflex designs do below their tuning. The distance between the front and the back of the cone is set by the path length of a QW, (and modified by the added air mass in the resonator) while a bass reflex box often has a much shorter distance between the front and the back side of the cone once the port stops acting as a resonant port.
A ROAR15 is tuned to 42 - 43 Hz but will put of lots of 35 Hz content with ease. The THAM12 is tuned to 60 - 62 Hz but will output lots of energy down to 45 Hz.
Look at the cone excursion graph in Hornresp. It does tell a whole other tale then the spl response graph.
A ROAR15 is tuned to 42 - 43 Hz but will put of lots of 35 Hz content with ease. The THAM12 is tuned to 60 - 62 Hz but will output lots of energy down to 45 Hz.
Look at the cone excursion graph in Hornresp. It does tell a whole other tale then the spl response graph.
Or at least it should do that. Hornresp fails to account for the nonlinear mass inertia of the air column inside a QW at high power levels.
A correctly designed QW will use the nonlinear behaviour of the air column to its advantage, while a bass reflex will get all the disadvantages of port turbulence and compression.
A often quoted rule of thumb for port air velocity in a bass reflex port is to never exceed 10 m/s at full power. A straight and well built QW keeps functioning well into supersonic speeds.
I think desiring 30hz is fair. But with room gain I doubt that you need better than -6db at 30hz for most things to enjoy it, maybe even -10db. So I'm not so sure it's an issue.
However it'd be nice to see a less sharp of a roll off (yes I understand why it looks how it does) because of the room gain tendency. I'd be worried about it a little modey for a home stereo.
However it'd be nice to see a less sharp of a roll off (yes I understand why it looks how it does) because of the room gain tendency. I'd be worried about it a little modey for a home stereo.
I brought up car audio because of the high tuning of the THAM15. If the lowest key of a piano is 27hz, then a 40-50hz BR/BP6 isn't going to cut it. I don't like sealed enclosures. They are nothing but distortion to my ears.
In a dual opposed roar I enter the squeezed down CSA to mimic the real aftect slightly? Between the magnets the occupied volume as CSA missing in that areas length (fudging it) sorta...
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I think we like the same kinda stuff
I’m trying to use 2 subwoofers now. One tuned low(mltl or big TL) and a tapped version up
Higher (roar, tham, Pflex, etc)?
Agreed!
its a broom! disquised the subwoofer perfectly! she avoids it at all moments and its never in danger of WAF...
im tryng..