posted
hey i thought there was a crazy idea area but i couldn;t find it so i posteed it here... now don;t bite my head off if this is ridiculous... cause it is....
ok bear with me... ok... picture making a "port" like an acetelyn cutting torch...
idea 1) a typical cylindrical port suurounded by 5 cone ports with teh small end facing out... in other words the air would be forced from a larger diameter to a smaller.
idea 2) a cone port with the small end facing in... suurounded by 5 cone ports with teh small end facing out
idea 3) 5 cone ports with teh small end facing out
remeber... even the light bulb was laughed at, at first
------------------ Not enough free cash to be a tru audiophile.... But a HECK of a good Woodworker/Carpenter with a desire to learn!!!!
Posts: 23 | From: nassau, ny usa | Registered: Jul 2000
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posted
Hmm, I am having some trouble putting these words into images but generally it sounds like you want to make the inside end of the port big and the outside end small, this really won't do anything except complicate tuning the port and increase port velocity which is bad. If I have got this wrong a diagram might be good.
posted
he's right. i know what you mean, one tapered port in the center (narrow end in the box) 5 tapered ports around the larger center one (narrow end outta the box) this won't really do you much except probably give you an ugly port whistle and be a real bugger to tune properly. picture the sound the torch makes, you don't want you box making that sound. plus i'm pretty sure they do that with the torch so that the accetlyne is pumped out the tiny holes, and when you squeeze the trigger oxygen is released through the center giving you a mighty hot flame, i think.
posted
you are both correct... would that no pu out incredible pressure though... especially if you built your wall so the port fired directly at the spl mic?????
------------------ Not enough free cash to be a tru audiophile.... But a HECK of a good Woodworker/Carpenter with a desire to learn!!!!
Posts: 23 | From: nassau, ny usa | Registered: Jul 2000
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posted
Try an experiment: Borrow or make a megaphone. Yell into the big end while pointing the small end at a friend 10feet away. Now turn it around and yell again!
The highest intensity in a speaker/port is right at the cone/opening. After there it gets less intense regardless of what was going on inside the box. Pro sound engineers use large horn shaped enclosures to help the speaker 'couple' with the air better - effectively making that high intensity air right at the cone move a larger mass of air.
In a torch, the nozzel is shaped that way simply for velocity. Technically, there is no pressure once it leaves the tip...
------------------ Blow your mind - PORT your box!
But dukk, pressure exerted on the microphone comes from the velocity of air molecules, right??? So if he built the port for air velocity, maybe he could get in effect a high "pressure" front??
ShadowStar
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HEY! I'm looking for a CHEAP used Clarion Thunderdome.. Hook me up!
Posts: 2578 | From: Somewhere In the Northeast | Registered: May 1999
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posted
I beleive that is how the Boss Cannon succeeded in it's outlaw record that first year it was around. I heard that they had this big funnel-looking fibreglass horn that went from the front of the woofers to over near the mic.... Essentially, the wall 'blew' on the mic.
In a Legal install I think the port would be too far away from the mic - but this IS only my opinion...
------------------ Blow your mind - PORT your box!
I guess that would be dictated by air velocity, which would be dictated by woofer excursion and frequency, eh... Hmm.. Time to whip out the TI-89 and go to work
ShadowStar
------------------
HEY! I'm looking for a CHEAP used Clarion Thunderdome.. Hook me up!
Posts: 2578 | From: Somewhere In the Northeast | Registered: May 1999
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