to KelticWizard (oh ye great one!)...
Not to put too fine a point on it BUT...
I believe we should be using the length of the longer pipe only, not the total length of the two pipes combined -- to determine "the lowest frequency we are trying to reproduce".
In my case the longer pipe is 15' or 18.75hz. The short pipe is 5' or 56.25hz. The two pipes in combination will give a flatter response curve over that frequency range range and more SPL than a traditional stuffed tapered single transmission line.
That's why I like to think of it as "the poor man's corner horn"
Regards
Joe
Not to put too fine a point on it BUT...
I believe we should be using the length of the longer pipe only, not the total length of the two pipes combined -- to determine "the lowest frequency we are trying to reproduce".
In my case the longer pipe is 15' or 18.75hz. The short pipe is 5' or 56.25hz. The two pipes in combination will give a flatter response curve over that frequency range range and more SPL than a traditional stuffed tapered single transmission line.
That's why I like to think of it as "the poor man's corner horn"
Regards
Joe
qi=
yes i have all those
i want my own horn,not a multiples stacked horn
2 or 4 per side...
im talking ONE sub only with one woofer,dont worry,ive nearly finished CADing
i dont have money to waste on another woofer when 1 does the job,and the labhorn has a midbass hole due to lack of rear chamber volume(because its assumed several boxes are used)
so its good for pro stacks,not necessarily for home moderate SPL use
www.geocities.com/sc00byd159
yes i have all those
i want my own horn,not a multiples stacked horn
2 or 4 per side...
im talking ONE sub only with one woofer,dont worry,ive nearly finished CADing
i dont have money to waste on another woofer when 1 does the job,and the labhorn has a midbass hole due to lack of rear chamber volume(because its assumed several boxes are used)
so its good for pro stacks,not necessarily for home moderate SPL use
www.geocities.com/sc00byd159
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
Folded horn design...
mikee12345,
nice job on your design!
With the angled corner placement from chart #2 you may break the 20hz barrier
I like your use of the driver's back-wave firing out the front.
How does that contribute to the overall sound and frequency response of the design?
Regards
Joe
mikee12345,
nice job on your design!
With the angled corner placement from chart #2 you may break the 20hz barrier
I like your use of the driver's back-wave firing out the front.
How does that contribute to the overall sound and frequency response of the design?
Regards
Joe
nonono it only 1 wave emanates from the box
that purple dimension on the front of it is just a dimension
Cheers.
if u like that one,you must like my 25hz horn...
for my friends new bedroom
120cm x 110cm x 40cm (approx)
yes he is crazy
1watt input.lab12 woofer.
that purple dimension on the front of it is just a dimension
Cheers.
if u like that one,you must like my 25hz horn...
for my friends new bedroom
120cm x 110cm x 40cm (approx)
yes he is crazy
1watt input.lab12 woofer.
An externally hosted image should be here but it was not working when we last tested it.
However, if we knew how to calculate and simulate the behavior of a Manifold, like those that appear on some current and vintage Electro-Voice bass bins, then it might be possible to model the horn as a back-loaded horn with a manifold, and then you'd really be out to win the unique design prize!
We should design a wave cannon for the Adire DPL12. It would be cool to have a design like that floating around. Though we may have to wait several years for the Bose patent to run out.
We should design a wave cannon for the Adire DPL12. It would be cool to have a design like that floating around. Though we may have to wait several years for the Bose patent to run out.
Help what length
Have been reading here for the last 2 weeks and are looking at make a move to make a wave canon but could some one help I have had sitting in my my room for a year a speaker out of a Bose Bose 302 Acoustimass Bass Loudspeaker I'm told this is what's used in the Bose Acoustic Wave Cannon (AWCS) I have found this:
" I saw where there is a Japanese version dubbed the AWCS-II-SR, at 88" it is 6 ft shorter than its big brother. The specs are in Japanese for the most part, but the numbers indicate a frequency response 18Hz higher on the low and 35Hz higher on the upper end than the 150" (U.S.)version, it looks like the AWCS-II-SR uses a OC-2 option card in the controller instead of an OC-1 card"
"The Material is not a standard size (10.5" O.D. x 10.25" I.D.)"
as we all know Bose use's allot of Eq so what im I asking is what lengths should I be looking at for good bass (sub Bass) at 40hz-20hz with little Eg or should I look at building a Bose 502B Acoustimass Bass Loudspeaker or a horn ???
thank you
hy-tek
Have been reading here for the last 2 weeks and are looking at make a move to make a wave canon but could some one help I have had sitting in my my room for a year a speaker out of a Bose Bose 302 Acoustimass Bass Loudspeaker I'm told this is what's used in the Bose Acoustic Wave Cannon (AWCS) I have found this:
" I saw where there is a Japanese version dubbed the AWCS-II-SR, at 88" it is 6 ft shorter than its big brother. The specs are in Japanese for the most part, but the numbers indicate a frequency response 18Hz higher on the low and 35Hz higher on the upper end than the 150" (U.S.)version, it looks like the AWCS-II-SR uses a OC-2 option card in the controller instead of an OC-1 card"
"The Material is not a standard size (10.5" O.D. x 10.25" I.D.)"
as we all know Bose use's allot of Eq so what im I asking is what lengths should I be looking at for good bass (sub Bass) at 40hz-20hz with little Eg or should I look at building a Bose 502B Acoustimass Bass Loudspeaker or a horn ???
thank you
hy-tek
If you want the hardest possible enclosure to build,build a basshorn.
a pipe is easy. Did u read the posts in this thread about how to calculate the pipe size?
if u can fit a HUGE long pipe,or a folded pipe the size of a closet,then go ahead
the largest horn i can fit is 240L (40hz only) but music is Mostly 40hz and above anyway...
its nice to go low tho
a pipe is easy. Did u read the posts in this thread about how to calculate the pipe size?
if u can fit a HUGE long pipe,or a folded pipe the size of a closet,then go ahead
the largest horn i can fit is 240L (40hz only) but music is Mostly 40hz and above anyway...
its nice to go low tho
If, by "acoustimass" you are referring to a sixth-order bandpass design, I wouldn't advise it, for what that's worth. I've built a pair of towers based on that design and was not pleased with the quality or quanity of bass. The transfer function phase looks like the Paris skyline, ditto the group delay promising terribly irregular subjective response. However, I also, more recently built a quarter-wave cannon such as discussed in this thread. With a five-inch woofer mounted a quarter of the way up a 12Ft pipe it produces an incredible amount of clean, accurate bass, quite sufficient for music at realistic levels in my small room. It leaves a little to be desired from the films, however, bottoming out in the Normandy Beach scene in Saving Private Ryan (the only thing I've really pushed it with). It is only a prototypal unit, obviously, to test the merit of the design for efficiency and accuracy and its extremely poorly sealed, but it sounds MUCH better than my 6OB towers, though that's the only other sub I've had sufficient experience with to compare it to so far.
I agree. Acoustimass is muddy and inarticulate, unlike the Bose Cannon which is deep and clean.
I would go with a 48" x 32" x 15" coffee table design (like my bed but smaller).
This will give you a long folded pipe of 139" or 24hz (each inner tube would be 46.5" x 12" x 6.5").
I would fire the ports downward for room gain.
You should be down about -3db at 20hz -- good for movie sound effects AND music.
Bose Cannon frequency reponse charts...
I found these sweeps from two years ago. They are alot more ragged than I remembered.
The measurements were done from my listening position. The room is 12' x 14'.
There are two nasty peaks introduced by the Cannons.
92db at 45hz
97db at 90hz
I third nasty peak (89db) is at 5k from the horn-loading of the five JBL HLS610s.
Also, I am -8db at 17hz, and -16db at 15hz -- worse than what I had previously indicated.
The green line is a sweep with the subs off.
The orange line is a difference sweep -- showing only what the subs are adding to the frequency response.
Notice that although the subs cross over at 80hz, they are still +7db at 160hz.
I have a 15' delay dialed in to the subwoofer home theatre setting, with a volume setting of -9db (this was set at +3db when the subs were in 4 cu ft boxes).
Clearly the cannons are MUCH more efficient than the ported boxes they replaced
I am writing Santa for an 1/3 octave EQ (wouldn't a Rane Parametric EQ be nice)...
I found these sweeps from two years ago. They are alot more ragged than I remembered.
The measurements were done from my listening position. The room is 12' x 14'.
There are two nasty peaks introduced by the Cannons.
92db at 45hz
97db at 90hz
I third nasty peak (89db) is at 5k from the horn-loading of the five JBL HLS610s.
Also, I am -8db at 17hz, and -16db at 15hz -- worse than what I had previously indicated.
The green line is a sweep with the subs off.
The orange line is a difference sweep -- showing only what the subs are adding to the frequency response.
Notice that although the subs cross over at 80hz, they are still +7db at 160hz.
I have a 15' delay dialed in to the subwoofer home theatre setting, with a volume setting of -9db (this was set at +3db when the subs were in 4 cu ft boxes).
Clearly the cannons are MUCH more efficient than the ported boxes they replaced
I am writing Santa for an 1/3 octave EQ (wouldn't a Rane Parametric EQ be nice)...
Attachments
Thank you
Thank you so much for your help !
I to agree to the acoustimass boxes are muddy and inarticulate (made for bands and djs, little boxes) I was only thinking of this as I can get the specs (measurements) to make 1/2 of (as I only have one 12" speaker). But I would love to have a cannon !! its got to be ... so thank you so much for your in put and time.
I think with with what you have give me here qi I can go out and make me a cannon !. It sounds like I will be very happy, and may be the wife? don't know about the people down the road?
before I make a coffee table design I think I will look into making and cannon tube ,will have to see about getting a cardboard-type tubing there must be some thing here, in Dunedin if not I may just look at making one out of wood. Nothing agents the coffee table, just I have room for the long tub be hind the TV (and it looks cool, for the boys !)
So think you and I'll let you know how I get on should, be look at make this in the next 2 weeks or so.
It will be from
I think lol
Thank you Let me know if you have any more to say on this.
hy-tek
ps Sorry it tock so long to get back here.
Thank you so much for your help !
I to agree to the acoustimass boxes are muddy and inarticulate (made for bands and djs, little boxes) I was only thinking of this as I can get the specs (measurements) to make 1/2 of (as I only have one 12" speaker). But I would love to have a cannon !! its got to be ... so thank you so much for your in put and time.
I think with with what you have give me here qi I can go out and make me a cannon !. It sounds like I will be very happy, and may be the wife? don't know about the people down the road?
before I make a coffee table design I think I will look into making and cannon tube ,will have to see about getting a cardboard-type tubing there must be some thing here, in Dunedin if not I may just look at making one out of wood. Nothing agents the coffee table, just I have room for the long tub be hind the TV (and it looks cool, for the boys !)
So think you and I'll let you know how I get on should, be look at make this in the next 2 weeks or so.
It will be from
I think lolThank you Let me know if you have any more to say on this.
hy-tek
ps Sorry it tock so long to get back here.
4,628,528 1986 now expired.
"The first and second openings are spaced apart a predetermined distance close enough together so as to avoid decreased low frequency performance and far enough apart to prevent deep notches in the system frequency response at higher frequencies. "
The optimum spacing is 1/2 the total length of the system, ie: if the front tube is 3', the rear tube is 9' and the system is bent or folded so the two openings are 6' apart.
This allows the system to be resonant at 3', 6', 9', and 12'. Without proper spacing the frequency response will not be as smooth, nor the gain as high.
" Preferably, the pressure wave transmission line means comprises a tube and said vibratile means comprises a diaphragm with the cross sectional area of said tube less than that of said diaphragm."
"the ratio of tube to cone areas (ATCR) typically controls the size of the system response peaks at the frequencies where the tube length is an odd multiple of a quarter wavelength for a single tube. For some typical speakers and an ATCR of 1 these peaks are relatively large. For ATCR of 0.5, the system response is relatively smooth"
The diameter of the tube should be SMALLER than the diameter of the cone.
"The free air resonant frequency of the loudspeaker driver may be chosen to be that at which the length of the longer of the tubes is a half wavelength and thereby lessen response irregularities that might be produced by resonances between reactive components of the loudspeaker driver and the tube."
The Fs of the driver should be lower than the 1/4W of the entire length of the tube.
" Preferably, the loudspeaker driver is overdamped to avoid undesired resonances between the loudspeaker and the tube."
A Qts of 0.3~0.4 rather than an infinite baffle Qts of 0.5~1.0
" It may be desirable to use equalization circuitry to insert a notch in the system response at a frequency below that for which the tube length is a quarter wavelength."
Use a subsonic filter.
"The first and second openings are spaced apart a predetermined distance close enough together so as to avoid decreased low frequency performance and far enough apart to prevent deep notches in the system frequency response at higher frequencies. "
The optimum spacing is 1/2 the total length of the system, ie: if the front tube is 3', the rear tube is 9' and the system is bent or folded so the two openings are 6' apart.
This allows the system to be resonant at 3', 6', 9', and 12'. Without proper spacing the frequency response will not be as smooth, nor the gain as high.
" Preferably, the pressure wave transmission line means comprises a tube and said vibratile means comprises a diaphragm with the cross sectional area of said tube less than that of said diaphragm."
"the ratio of tube to cone areas (ATCR) typically controls the size of the system response peaks at the frequencies where the tube length is an odd multiple of a quarter wavelength for a single tube. For some typical speakers and an ATCR of 1 these peaks are relatively large. For ATCR of 0.5, the system response is relatively smooth"
The diameter of the tube should be SMALLER than the diameter of the cone.
"The free air resonant frequency of the loudspeaker driver may be chosen to be that at which the length of the longer of the tubes is a half wavelength and thereby lessen response irregularities that might be produced by resonances between reactive components of the loudspeaker driver and the tube."
The Fs of the driver should be lower than the 1/4W of the entire length of the tube.
" Preferably, the loudspeaker driver is overdamped to avoid undesired resonances between the loudspeaker and the tube."
A Qts of 0.3~0.4 rather than an infinite baffle Qts of 0.5~1.0
" It may be desirable to use equalization circuitry to insert a notch in the system response at a frequency below that for which the tube length is a quarter wavelength."
Use a subsonic filter.
There are programs around that should be capable of doing such things (apart from writing one by yourself !), one of them is AJHorn:
http://www.aj-systems.de/indexe.htm
Regards
Charles
http://www.aj-systems.de/indexe.htm
Regards
Charles
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