keele line array, bad start...

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Adason, what tweeters are you using?

If I built CBTs I would but two side pieces with the proper curve (router or jigsaw) then create the baffle by gluing on mutiple layers of 1/8" or 1/4" untempered hardboard (aka Masonite. The tempered version doesn't glue as well). Then a jig that matches the curve and sits on the baffle to hold a router for the speaker cutouts. A bit of work to make the jig but it would make the cutting way faster and more accurate.

Good luck and keep posting!

bearberry
 
Adason, what tweeters are you using?

If I built CBTs I would but two side pieces with the proper curve (router or jigsaw) then create the baffle by gluing on mutiple layers of 1/8" or 1/4" untempered hardboard (aka Masonite. The tempered version doesn't glue as well). Then a jig that matches the curve and sits on the baffle to hold a router for the speaker cutouts. A bit of work to make the jig but it would make the cutting way faster and more accurate.

Good luck and keep posting!

bearberry

Must be an echo in here? :D
Think I said pretty much that already?
But thanks for confirming...

_-_-baer
 
music soothes the savage beast
Joined 2004
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this is what I did if anyone is interested
its not finished, it needs tweeters, but it has been playing nicely alredy
 

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As far as I remember talking to Don Keele and reading his papers, shading is essential, so don't hold back. You would not be using the same resistor array for woofers and tweeters, right? Or would you?

Don's prototype I listened to had the drivers shaded by sections of 6 each.
 
Thank you Adason,

Since building my 2-way line arrays with a dozen 5" Sony mid-woofers and 48 (Apex Jr.) JBL/Audax 10mm dome tweeters--it has been an issue to get the tweeters and 5 inchers to sound right at the 4,300Hz XO point. I have a big dip at the 1 to 4KHz region and it does not sound "right".

Those Aurasound 3" FRs would work perfectly crossed at 400Hz from the 5" woofers then crossed at 4,300Hz to the tweeter line. Their 80mm diameter frames are at exactly 1 wavelength at 4,300 Hz so I can take care of the beaming issues. The smooth response (without EQ) from 400Hz with a mild rise from 1KHz to 4KHz is about perfect for a "passive" line array.

Considering your experience with them, do you think 21 of them would have any issues being crossed at 400Hz with a 2nd order 12dB/Oct passive filter? My use would be in a garage but I'd like to get them to play well with classical music--the big sound and dynamics of the arrays should work well with the demands of classical music.

After viewing what you've done with a jig saw and drill, my Roto-Zip seems to be overboard in wood crafting technology. Would you suggest using the plumber's putty trick on the Aura frames or are they solid enough not to "ring"?
 
music soothes the savage beast
Joined 2004
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I'm curious, what brand/model RTA and its vertical scale?

GM

that was behringer ultracurve esp8024
sorry, it was on auto range, no way for me to know the scale, but in few days I will brink laptop with holm impulse to measure more usefull fr responses

that quick check with rta was for me just to know what I am listening to unequalized
 
music soothes the savage beast
Joined 2004
Paid Member
Thank you Adason,

Since building my 2-way line arrays with a dozen 5" Sony mid-woofers and 48 (Apex Jr.) JBL/Audax 10mm dome tweeters--it has been an issue to get the tweeters and 5 inchers to sound right at the 4,300Hz XO point. I have a big dip at the 1 to 4KHz region and it does not sound "right".

Those Aurasound 3" FRs would work perfectly crossed at 400Hz from the 5" woofers then crossed at 4,300Hz to the tweeter line. Their 80mm diameter frames are at exactly 1 wavelength at 4,300 Hz so I can take care of the beaming issues. The smooth response (without EQ) from 400Hz with a mild rise from 1KHz to 4KHz is about perfect for a "passive" line array.

Considering your experience with them, do you think 21 of them would have any issues being crossed at 400Hz with a 2nd order 12dB/Oct passive filter? My use would be in a garage but I'd like to get them to play well with classical music--the big sound and dynamics of the arrays should work well with the demands of classical music.

After viewing what you've done with a jig saw and drill, my Roto-Zip seems to be overboard in wood crafting technology. Would you suggest using the plumber's putty trick on the Aura frames or are they solid enough not to "ring"?

18Hurts, I am sure you can cross Aura at 400Hz, their Fs is about 150Hz. I am crossing them actively to the sub at 160Hz. Thats what I have right now, one spare line level crossover 160Hz, that might change.

The Aura's are great sounding, before I decided to buy potload of them, I tested short array of four per side, all four parallel, giving 4 ohms. That sounded great. I recommend these speakers, they are well built.

Putty would definitely help, but I would not bother, at normal listening levels each one is receiving miniscule power not to ring. My opinion. I definitely have not heard any ringing.

Considering they cost $1.50 each, I would not hesitate, go and get some.
 
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