So I am gonna build a garage, and have a 12” sub that is going in it. I plan to bury the transmission line under the concrete, and run the entire span of this garage.
Now the question: Can the t line be divided? (Think vents, but instead of one section that equals the t line, we take the section, divide it into 2 or more “vents” and that equals the section as a whole)
My sub is 25hz, and 85 sq in for sd.
I was thinking 4 separate sections to equal the full wave length “instead of quarter wave”
Will this work?
Now the question: Can the t line be divided? (Think vents, but instead of one section that equals the t line, we take the section, divide it into 2 or more “vents” and that equals the section as a whole)
My sub is 25hz, and 85 sq in for sd.
I was thinking 4 separate sections to equal the full wave length “instead of quarter wave”
Will this work?
I understand what you’re telling me, but maybe I didn’t explain it right…
I will need a 10 inch diameter pipe approximately 45.2 feet long
Instead can I do 4x 2 inch “vents” that are 12 feet long
Clear as mud, huh?
I will need a 10 inch diameter pipe approximately 45.2 feet long
Instead can I do 4x 2 inch “vents” that are 12 feet long
Clear as mud, huh?
So the driver is in a box feeding four 1/4 WL reflex vents tuned to 25 Hz? If so, don't see why not.
That’s the idea exactly! I was hoping with this I could essentially make the vents add a sort of “phantom speaker effect" in certain locations to better fill the room.
No different in concept to Dr. Geddes' multiple subwoofer alignment and did some early hi-end FP HTs with three subs where one was behind the screen up at 2/3 screen height where dialog is centered, one placed 1/3 up a side wall and the other at 2/3 back at the other side wall/floor. Note that these were tapered wall, ceiling like actual cinemas, so may need different locales in a typical boxed room.
I'm no expert on TL's, but what you're proposing sounds like a bass reflex box with really long ports. Not a TL enclosure.
You’re correct in your response. It is.
With this setup, however, I would not use a tl design. I would use the tl thought process, though.
So:
1- split the 10 inches into equal diameter pipes
2- make them all the length of the quarter wave
The question: would this work “like a t line” in order to better fill the room?
With this setup, however, I would not use a tl design. I would use the tl thought process, though.
So:
1- split the 10 inches into equal diameter pipes
2- make them all the length of the quarter wave
The question: would this work “like a t line” in order to better fill the room?
You should theoretically get better fill in the room, by virtue of having several distributed sound sources. Whether the pipes were acting as transmission lines, or not, has no correlation to that. The optimum port locations and corresponding lengths will be more dependent on your room than a simple quarter wave calculation.
I also want to mention that, (4) 2" dia 12' long pipes provides far less cross sectional area and volume than a 10" dia 45' long pipe, so I would hardly call these equivalents.
I also want to mention that, (4) 2" dia 12' long pipes provides far less cross sectional area and volume than a 10" dia 45' long pipe, so I would hardly call these equivalents.
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Again correct you are!
So, regardless of the math, think 4 quarter wave length “vents” at 2.5” in diameter, and 11.3’ in length.
Will that add the desired effect?
(I doubt my wife will approve extra SW’s)
So, regardless of the math, think 4 quarter wave length “vents” at 2.5” in diameter, and 11.3’ in length.
Will that add the desired effect?
(I doubt my wife will approve extra SW’s)
http://hyperphysics.phy-astr.gsu.edu/hbase/Waves/opecol.html#c1
Check at the difference between a 45 foot pipe and a 12 foot pipe resonator tunings?
Check at the difference between a 45 foot pipe and a 12 foot pipe resonator tunings?
http://hyperphysics.phy-astr.gsu.edu/hbase/Waves/opecol.html#c1
Check at the difference between a 45 foot pipe and a 12 foot pipe resonator tunings?
I did, and immensely thank you for the site. With that, though, the “1/4 wave theory” is still about 12 feet in length to reach 28hz being the “magic spot”.
In those regards, the proposed vents (or resonators) should hit around 25-28hz. Thirdicomplex is correct with what was argued.
While I love the banter back and forth over this the question is:
Can a single sub be used in an enclosure to “mimic” this http://gedlee.azurewebsites.net/Papers/multiple subs.pdf
To get the most balance throughout the room?
(Of course this is the best option without extra subs)
Check at the difference between a 45 foot pipe and a 12 foot pipe resonator tunings?
I did, and immensely thank you for the site. With that, though, the “1/4 wave theory” is still about 12 feet in length to reach 28hz being the “magic spot”.
In those regards, the proposed vents (or resonators) should hit around 25-28hz. Thirdicomplex is correct with what was argued.
While I love the banter back and forth over this the question is:
Can a single sub be used in an enclosure to “mimic” this http://gedlee.azurewebsites.net/Papers/multiple subs.pdf
To get the most balance throughout the room?
(Of course this is the best option without extra subs)
Hmm, another 'knee jerk' response gone wrong 
, i.e. when a driver/whatever is coupled to a pipe it's a 1/4 WL resonator (TL), but if driven by a box's stored energy, i.e. reflex w/ vent(s), then its vent system will be 1/2 WL resonators, so easiest to use a box program to find the proper length for 'x' tuning with 'y' diameter piping.