What you are presenting is a subjectivist argument.
How would the winner of this hypothetical contest be determined?
By virtue of your perception alone?
I guarantee you that the competition in this contest would be using measurement and computers
I'm not busting your chops here - merely presenting the perspective from my background. I built my 1st horn around 1971 from a Klipsch design, and continued to dabble and accumulate as much material on horns since.
Reverse engineering has the drawback of lagging behind the curve so to speak.
Transducers can look identical yet have vastly differing performance.
I am very familiar with the scientific method and the flaws with human perception including expectation bias and what I call builder's bias.
Agreed; Ultimately the ear must be pleased, but perception is not uniform and often based upon experience.
One perception's changes when provided a better experience.
IE: I thought that was good until I experienced ( tasted/saw/heard/ etc ) something better.
several forum members have offered excellent advice.
others seem to have horsehair in their underwear.
Probably due to the fact that this thread red-herring'd into "choosing an existing design", much like this one, right below it:
http://www.diyaudio.com/forums/subw...ck-comparison-top-5-big-subs-here-please.html
rather than it's original intent, was to use a computer to discuss not using a computer.
What does a guy sticking empty toilet paper rolls into the port of a plastic chinese midrange-loaded bandpass subwoofer with a $2.99 amplifier have to do with designing a proper subwoofer without a computer?
Start off with the effective area of the driver, give it a 2:1 compression ratio @ the throat and expand the horn with 20-30 % flare rate per foot. Make the total horn length 1/4 of the length of the wavelength that the closed box's f3 behind the driver is. A good sized box for a horn is 2'wide *4high ' * 2' deep, this way if you fold it well you can use the 2' * 4' dimension as a large horn mouth. With folding you may only be able to use 24"* 40"of that mouth opening. Of course I may get SLAMMED for suggesting this but it worked for me for my first horn 5 years ago when I had no computer or programs. I first took a piece of paper and drew a scale 4' * 2' box on it (elevation view) then plotted the divers position close to one of the corners and started the horn flare from there, using the space around the driver for folds (keeping in mind you will need sealed box area behind the driver) and then usually send the flare down the backside of the box turn the corner @ the bottom and expand the flare towards the 2' * 4' opening. Then tinker with all the folds and lengths till you have something that looks good and is long enough. It won't have a flat response but you can always use some processing to help that. Hopefully this is a good start.
Out of anger, I made my 3rd attempt at using that program. Finally, result!
I guessed at the parameters of the tapped horns linked in my sig, got a result that was somewhere near to what I'm hearing. Just with bigger peaks. The peak at 70Hz is >95dB on my sim, <90dB on lilmike's.
PS - reverse-engineering something such as a TH is difficult, as I've spent the past couple of hours learning.
Last edited:
I suspect that Paul Klipsch didn't have much for computers back in the '40s when he got a patent for a horn design. He certainly achieved more than a little success. Trial and error is a lot different than random trial and error; you have to learn from your mistakes. Knowing a bit of physics will help you go in the right directions as well. As shown above there are some general rules to give you a good head start. That said, computers have allowed much more detailed analysis, and as a result, the bar has been raised far beyond what could be done in the past. By today's standards you probably can't do a competitive and respectable design without some computer based measurement and analysis. So, do you have high standards or low standards?
Probably not, but he was also a brilliant inventor and eccentric, having more patents for stuff than you could shake a stick at. I mean, who else would name a speaker "Heresy".
Klipsch drew from prior work
This Voight Tractrix was patent in 1927
This Voight Tractrix was patent in 1927
An externally hosted image should be here but it was not working when we last tested it.
yep, paul klipsch.... cowboy with a slide rule...great guy. Knew how to use keys to a car... and also knew:
"On Horn Design -" Simple. A horn is just a reasonably rigid boundary for
an air column. Now all you
have to do is figure what shape to make it."
http://community.klipsch.com/forums/storage/9/900044/PaulWKlipsch.ArkansasSpeakerMaker.pdf
"On Horn Design -" Simple. A horn is just a reasonably rigid boundary for
an air column. Now all you
have to do is figure what shape to make it."
http://community.klipsch.com/forums/storage/9/900044/PaulWKlipsch.ArkansasSpeakerMaker.pdf
I'd make a straight horn, no folds
The absolute simplest horn type construction is a BiB, a box with a single board in the thing. The woofer fires out the front and the horn exits at the top. For general screwing around, it would be the most simple design. Down side it is huge! (BiB stands for Bigger is Better)
Make the very tall box, the board sits locked in one corner and is set to an angle that makes the board even in distance front to back and board edge to the bottom of the box. For example, the board would have 8" from the front panel...8" from the board end to the back panel--and 8" from the bottom of the box to the edge of the panel. All dimensions are identical.
The program is really simple, enter three parameters for the speaker. Fs (resonant frequency) Qts and Vas. The BiB program spits out the box size, it's tuning and how to build it. Be careful though, it will tune the box to one octave below Fs. Since it has a path, this makes the box very large so a high Fs speaker is best.
I've never built one but they do seem interesting for small 4 to 8" full range speakers to push the bass level up. Have no idea what kind of gain you'll get over ported but the design seems to be for extending bass down.
The example below is for a small full range speaker tuned for 40Hz. Z-driver is distance from the top (center of driver) and a-b-c is the distance of the bottom of the board to front, back and bottom of the box. 42" high is not too bad but a Beta 18 is over 10 feet high, 27" wide and almost 4.5 feet deep. Easy to build though--you said you wanted big.
Driver FE 103
Fs 80
Vas 0.24
Qts 0.35
Line Length 84.153
Folded Height 42.077
Vb 1.292
Sm 53.067
Depth 8.663
Width 6.126
zdriver 18.261
a-b-c 4.332
Conversion
Liters
Cubic Feet
0
Cabinet
Wood Width 0.500
Outside Dimensions
Width 7.126
Depth 9.663
Height 42.077
Rounded Dimensions
Width 7.000
Depth 9.500
Height 42.000
Cut Boards Per Box
Front/Back 2 each
Width 7.000
Length 42.000
Sides 2 each
Width 8.500
Length 42.000
Slant 1 each
Width 6.000
Length 37.061
Bottom 1 each
Width 6.000
Length 8.500
The absolute simplest horn type construction is a BiB, a box with a single board in the thing. The woofer fires out the front and the horn exits at the top. For general screwing around, it would be the most simple design. Down side it is huge! (BiB stands for Bigger is Better)
Make the very tall box, the board sits locked in one corner and is set to an angle that makes the board even in distance front to back and board edge to the bottom of the box. For example, the board would have 8" from the front panel...8" from the board end to the back panel--and 8" from the bottom of the box to the edge of the panel. All dimensions are identical.
The program is really simple, enter three parameters for the speaker. Fs (resonant frequency) Qts and Vas. The BiB program spits out the box size, it's tuning and how to build it. Be careful though, it will tune the box to one octave below Fs. Since it has a path, this makes the box very large so a high Fs speaker is best.
I've never built one but they do seem interesting for small 4 to 8" full range speakers to push the bass level up. Have no idea what kind of gain you'll get over ported but the design seems to be for extending bass down.
The example below is for a small full range speaker tuned for 40Hz. Z-driver is distance from the top (center of driver) and a-b-c is the distance of the bottom of the board to front, back and bottom of the box. 42" high is not too bad but a Beta 18 is over 10 feet high, 27" wide and almost 4.5 feet deep. Easy to build though--you said you wanted big.
Driver FE 103
Fs 80
Vas 0.24
Qts 0.35
Line Length 84.153
Folded Height 42.077
Vb 1.292
Sm 53.067
Depth 8.663
Width 6.126
zdriver 18.261
a-b-c 4.332
Conversion
Liters
Cubic Feet
0
Cabinet
Wood Width 0.500
Outside Dimensions
Width 7.126
Depth 9.663
Height 42.077
Rounded Dimensions
Width 7.000
Depth 9.500
Height 42.000
Cut Boards Per Box
Front/Back 2 each
Width 7.000
Length 42.000
Sides 2 each
Width 8.500
Length 42.000
Slant 1 each
Width 6.000
Length 37.061
Bottom 1 each
Width 6.000
Length 8.500
* read this to understand how horns (and a lots of other audio devices) work http://www.vias.org/crowhurstba/crowhurst_basic_audio_vol1_048.html
Assuming
1. you are willing to use your head or a calculator for basic arithmetic,
2. know the T/S parameters of the driver,
* read this for the basics of horn design: Horn Design
Assuming
1. you are willing to use your head or a calculator for basic arithmetic,
2. know the T/S parameters of the driver,
* read this for the basics of horn design: Horn Design
Last edited:
Note the last line on that link posted by zobsky:
"However nothing beats actually building the horn and measuring it."
( emphasis mine )
And the first part:
When you design a horn, you have several criteria:
* What frequency response you desire
* What driver you will use (and its parameters)
* How much compromise you are willing to accept (size, shape, materials, etc
The OP was hypothetical and vague not listing the design criteria or how much compromise...
I haven't heard the Horn Massive personally
Horn Massive
( Plans are on-line But it costs $8000 in 2004. )
I have heard (8) bass horns with mouths 8' square.
And of course there are larger horns, that would cost more than $10,000 to fabricate.
"However nothing beats actually building the horn and measuring it."
( emphasis mine )
And the first part:
When you design a horn, you have several criteria:
* What frequency response you desire
* What driver you will use (and its parameters)
* How much compromise you are willing to accept (size, shape, materials, etc
The OP was hypothetical and vague not listing the design criteria or how much compromise...
I haven't heard the Horn Massive personally
Horn Massive
( Plans are on-line But it costs $8000 in 2004. )
I have heard (8) bass horns with mouths 8' square.
And of course there are larger horns, that would cost more than $10,000 to fabricate.
Last edited:
My sub system
I chose a more conventional tack in my subwoofer system. I used four JBL 2245H (18") drivers mounted in four 12 cu. ft. cabinets (tuned port to 20 Hz). The subs are driven by two BGW 750C power amps.
Tim
I chose a more conventional tack in my subwoofer system. I used four JBL 2245H (18") drivers mounted in four 12 cu. ft. cabinets (tuned port to 20 Hz). The subs are driven by two BGW 750C power amps.
Tim
Clarification of previous posts
Post #491:"...you have suggested 2 different designs..."
Hi 60ndown,
Just to clarify: I was trying to provide you with one external box with different internal dividers. I was under the apparently mistaken impression, that you want to experiment with different drivers, and horn designs without being hamstrung by mathematical considerations, and without the use of simulations software. These are not complete designs, but more in the spirit of layout experimentation. If you were to take the time to look at the sketches in some detail you would see that you are looking at a FLH, and a TH sharing substantial pieces of wood while allowing for ample room for experimentation.
Regards,
Post #491:"...you have suggested 2 different designs..."
Hi 60ndown,
Just to clarify: I was trying to provide you with one external box with different internal dividers. I was under the apparently mistaken impression, that you want to experiment with different drivers, and horn designs without being hamstrung by mathematical considerations, and without the use of simulations software. These are not complete designs, but more in the spirit of layout experimentation. If you were to take the time to look at the sketches in some detail you would see that you are looking at a FLH, and a TH sharing substantial pieces of wood while allowing for ample room for experimentation.
Regards,
another 4 hours well spent 🙂
my first T.L, T.H ??
(what is the difference between a 'transmission line' and a tapped horn?)
it was a little tricky getting the panels in the right location *note to self* put markings for outside of box on the plywood first.
how ever i did do the math on this one,
there are 2 drivers in it,
and they're 8s, and different brands (i figure they will balance each other out)?
initial listening tests on music are very good, it gets VERY low (much lower then the 'kuad kouppler", seems more efficient then the 'kuad kouppler' (doesnt require bass boost on my source to fill the room with bass)
cant say for sure about much as the glue and caulk are still very wet 😀
ive been listening to it for 40 minutes and it seems to be excellent 🙂
nothing offensive yet on random mp3s.
An externally hosted image should be here but it was not working when we last tested it.
my first T.L, T.H ??
(what is the difference between a 'transmission line' and a tapped horn?)
it was a little tricky getting the panels in the right location *note to self* put markings for outside of box on the plywood first.
how ever i did do the math on this one,
there are 2 drivers in it,
and they're 8s, and different brands (i figure they will balance each other out)?
initial listening tests on music are very good, it gets VERY low (much lower then the 'kuad kouppler", seems more efficient then the 'kuad kouppler' (doesnt require bass boost on my source to fill the room with bass)
cant say for sure about much as the glue and caulk are still very wet 😀
ive been listening to it for 40 minutes and it seems to be excellent 🙂
nothing offensive yet on random mp3s.
- Status
- Not open for further replies.