Wooden jam jar

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[quote author="sodderboy"]Totally cool, and totally instant divorce if I brought something like that into the living room. "It's not a hole babe, it's a subwoofer horn".
[/quote]

So what?
You can make it under a table. However, nothing must stay on it when it works... Or you man not need it: only some movies have freqs below 40 Hz, the rest contains only a noise so I almost every time keep it off.

PS: and what's that about concrete sheets? Kinky schtupf :shock:

I saw some in Home Depot. I think a carpet glue will work.
 
[quote author="Freq Band"][quote author="Wavebourn"]
For curved surfaces? :roll:
They will look like a Space Shuttle. :cool:[/quote]

Like this

[/quote]

Nice, I want to make woofers spherical...
 
Horn coupling is great for efficiency but generally a weakness when it comes to transient/impulse response. -They're usually VERY impressive if you're impressed by apparent acoustic 'size', but they invariably sound awful to me. -Actually there was ONE set which was built by a designer in the central valley area of California which sounded pretty close to me, but even so, I had to tell the builder that they were the best HORN LOADED speakers that I'd ever heard, but that sentence is only true with as long as you keep the words "Horn loaded" in there.

line arrays generate part of the appearance of lower acoustic output falloff with distance by cancellation at closer distances and more efficient spectrum-wide adding/summing/reinforcement at greater distances... translation: the closer you get, the worse they usually sound. They generally find use in cathedrals, arenas and other areas where the acoustics are so terrible that anything else would be a washy, echoey nightmare. -In comfortable acoustic rooms I've yet to meet a set which didn't sound deeply flawed, and until they repeal some of the laws of physics, I doubt I ever will...

In short, line arrays are handy for lousy environments, but part of what makes them work is what makes them sound so terrible to my ears.

Every speaker design has flaws and problems, and each approach usually has sinificant advantages. -For most people, the traditional cone woofer/soft-dome tweeter approach is the most acceptable compromise. -For me it's the electrostatic approach, with perhaps an LF cone woofer crossover, a-la Martin Logan. These bring a serious acoustic challenge to controlling what comes out from the BACK, but are unmatched in terms of detail. -I only wish my wife would let me bring a set home.

Keith
 
[quote author="SSLtech"]

In short, line arrays are handy for lousy environments, but part of what makes them work is what makes them sound so terrible to my ears.
[/quote]

You never heard mine. ;)

There are theoretical beliefs, there is the reality. They are different very often. In line arrays "size matters", in respect to frequencies. My tweeters are 12 mm in diameters, mid-rangers are 4", all of them are mounted as close to each other as possible. If made properly line arrays do not cancel sound pressure, they shape an acoustic wave. An energy does not go to heat, it is preserved and directed properly.

Speaking of my horn, it works below 40 Hz. I would not use horns for higher frequencies. Exception: if to listen to Louis Armstrong only, may be...

For analogy, a horn is like a flashlight with a reflector. A line array is like a flash light with a lens. You can use a lens like in flash light for your photo camera to get clear picture, but you can't use a reflector from the same flash light. Fresnel's mathematics may be applied for speakers...
 
White light and sound are completely different, and Fresnels math is irrelevant when you consider slot diffraction... which is MUCH more appropriate and relevant to audio in terms of an analogy.

Phase cancellation is impossible to avoid from identical-signal equal-level sources, unless they've repealed another law of physics and forgotten to copy me on the memo... and multiple-repeat-spaced drivers are by far the worst-case example.

Granted, people like what they like, but line arrays only actually sum perfectly at infinite distance. -I usually like them as far away from me as possible, so that sounds about right! :wink:

Keith
 
Distance does not matter (practically) if sizes of drivers are selected according to highest frequency they are allowed to fire out. You are right if to remove all drivers between top one and bottom one, but as soon as there are many of them, and they are close to each other they sound almost like ribbons, but are much more effective. John Curl recently told by phone how they made huge arrays on stadium that sounded better than home Hi-fi; they used multiple sizes and many frequency bands. When I see dragon tails on stadiums made of active speakers 20" spaced, with horn tweeters each, connected through Ethernet to align by computer, I understand why people believe that line arrays are horrible things.
But I'm still searching for drivers with coils of close to cone diameters (not necessary cone, it may be a hemi-sphere or what else), light but stiff, with lowest FS as possible (I mean so called dynamic drivers). Foster have one, but they don't answer on e-mail and phone calls.
 
The Harman-developed Odyssey drivers, which everyone has copied but few very successfully, are mostly neo motor with the voice coil about the diameter of the convex aluminum cone. The foam surround is the only suspension (no spider). They blundered badly by not immediately seeking a design patent---instead they went after a utility patent and bungled the job execrably.

But they probably won't return your phone calls either (hint: it's not you :razz: ). It's that you're not likely to buy a million pieces of the little buggers.
 
[quote author="bcarso"]The Harman-developed Odyssey drivers, which everyone has copied but few very successfully, are mostly neo motor with the voice coil about the diameter of the convex aluminum cone. The foam surround is the only suspension (no spider). They blundered badly by not immediately seeking a design patent---instead they went after a utility patent and bungled the job execrably.

But they probably won't return your phone calls either (hint: it's not you :razz: ). It's that you're not likely to buy a million pieces of the little buggers.[/quote]

Bad for them... My friend's father used to run a PCB business in Silicone Valley, when a guy with long hair wearing old jeans went and promised to make them rich, very rich... His father did not laugh... And he was very rich, the guy told the truth...

Edit: when I saw that transparent speakers made by Kardon connected to Apple computer, I drooled: I would take such drivers and put them very close to each other... 6 feet tall tubes would sound gorgeous!
 
So I can imagine its like one of those systems where the dude is watching Quincy or Hollywood Squares and it sounds like you are on the Starship Enterprise?

Cool, but I'll keep my Design Acoustics (2.0) and the missus.

And the cement sheets are called "wonderboard" and it is best to use liquid nails to keep them in place. I always kick them off to the floor in the summer :green:

Mike
 
[quote author="sodderboy"]

And the cement sheets are called "wonderboard" and it is best to use liquid nails to keep them in place.
[/quote]

Yes, it is what I meant! :grin:
 
Finished monitor (rubber covered)

shelfjet_rubber_f.gif
 
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