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Old 26th March 2013, 01:40 PM   #11
more10 is offline more10  Sweden
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The reason for the W shape is ease of construction. The driver compartment and back chamber is simpler to build than a horn with one horn path.

The total length is only one leg of the W, but the mouth area is the two mouths together.

If you get a miniDSP 4x10 Hd you can delay your other speakers so that they dont canel each other out at crossover frequencies. You will get a harder bass.
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Old 26th March 2013, 02:29 PM   #12
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Yes Larry not Leroy, what was I thinking? I met Richard Long in 1985 when we did a club with him. Richard believed most speakers were compromised with not a long or large enough horn or mouth area to be cheaper to build, sell, and transport. Gary Stewart Audio and Sound by Shorty are 2 still using a lot of Richarid's basic designs, updated where possible and original components are unavaiable, the basic concepts - RLA 3000 crossover and cabinets of the Paradise Garage system is pretty much what Gary Stewart still uses. Yes all of them gone too soon, the clubbing lifestyle and AIDS.
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Old 26th March 2013, 04:50 PM   #13
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Quote:
Originally Posted by arrie View Post
my understanding regarding horn response is that horn length are related to SPL and mouth area are related to low cut-off frequency. am i on the right path here?
Both are important, but you basically have it backwards, long path=low, large mouth=loud.
In multiples, horns make up for small mouth area, not so much for short path length.
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Old 27th March 2013, 11:23 AM   #14
arrie is offline arrie  South Africa
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This coming Easter weekend i am just going to build another EAW, thus eliminating all the phasing and delay issues.
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Old 27th March 2013, 02:40 PM   #15
epa is offline epa  Netherlands
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nevermind,i should refresh more often
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one good thing about music ,when it hit you feel no pain.
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Old 27th March 2013, 04:02 PM   #16
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Quote:
Originally Posted by arrie View Post
This coming Easter weekend i am just going to build another EAW, thus eliminating all the phasing and delay issues.
You still need to time align (delay) the top cabinets to avoid phasing and delay issues, but going with the same sub designs reduces those issues at lower frequencies.
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Old 27th March 2013, 04:11 PM   #17
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The crossover on a horn mouth extension Bertha should be 100hz on the top end. The ear isn't too sensitive to low frequency phase. Stacking the mid and high cabinets at the rear of the Bertha/Levan cabinet will minimize the phase difference and was the reason the systems were stacked this way, rather than the horn mouths aligned with front stacking the upper end cabinets

Last edited by ticknpop; 27th March 2013 at 04:13 PM.
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Old 27th March 2013, 06:01 PM   #18
djlivex is offline djlivex  United States
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Default Big Bertha

Been exposed to those bass notes in the early 80's with Studio 54 and Palladium night clubs. Those Bertha's with the Levan horn threw some massive in your chest bass like a freight train.

I am still contemplating on building 4 Emeralds (half Bertha) with a tear down Levan Horn I still do not know how to start the extension horn maybe with massive bolts and plates.

Also the drawings of the Bertha on the net EAW is 15 mm BB. But the original is 18 mm BB would doing the Emerald's in 15 mm would change the tuning of the cabinet since thinner walls more air movement??? Thanks!
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Old 29th March 2013, 12:48 PM   #19
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Hi, For best sound always use same type of speakers in each band. Time and phase problems might reduce output in large stacks of miss matched cabs. Please show us a drawing of how you ported the 882 copy. Thanx, VECTORDJ
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Old 8th April 2013, 03:25 AM   #20
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The Levan mouth bolted/screwed on to 3 or 4 inches of the left and right side of the Bertha. The Levan mouth was built as left and right sides which the front top to bottom braces bolted together and the nose left and right sides glued together. same for the Emerald. The mouth only attached on the sides, the front nose of the horn didn't attached to the Bertha, it was just part off the mouth extension.( I built the 10 foot and 8 foot mouths on sites) The Bertha was 42 x 36 x 60 - size limited by what would fit through a fire exit door to get it into a club and why the mouths were always assembled on site. The Emerald got it's name from the Emerald City Disco in New Jersey where it was first used, the RLA Waldorf got it's name from the Waldorf Astoria.

18Mm would be better, but heavier, 15mm works too - depends on how good a cabinet maker you are more than the thickness. Tuning wouldn't be affected. Not sure why porting is of interest, the mouth extension would add LF extension and porting can be hard on cones in ported horn boxes.

Phase isn't so audible at 100 Hz.

Last edited by ticknpop; 8th April 2013 at 03:53 AM.
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