i was reading in january's AS&S and i saw i car that had a single 12 (i think) and the installer made a plate that sat just above the woofer, with one small hole for aor movement. he claimed that the plat created a small pressure poacket between the sub and the plate and that this pressure restricted cone movement. he claimed this resulted in a increase in spl of 1db and produced a more natural sounding bass response.
did anyone see this guy in that mag? also, anyone know about the detials for constructing such a plate?
posted
I read about a similar piece in an old CA&E. It was in a letter, and they called it a loading board. It was most commonly used in convertibles and vehicles with large air spaces to control the bass so it didn't all escape. I'll try and find the issue and post more info. They gave specs which worked in general for different size subs. There was no mention (from what I recall) of a hole in the board.
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Posts: 490 | From: Fort Frances, Ontario, Canada | Registered: May 1999
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i might not be sure about the hole, i don't have the issue with me (i am at work and working very hard hehehe...) i'll check when i get home and verify. i am kinda curious
posted
I don't know much about it other than the CA&E issue mentioned above. If it helps though it was in Drew Bledsoe's porcshe convertible, the plate was over some soundstream spl 160's if memory serves me correctly. Why do I remember that, it was like years ago.
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Posts: 141 | From: Bloomsburg, PA, USA | Registered: Dec 1999
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posted
The box in drew bledso's porche was slot loaded, I have had a little experience with this type of design, but i have never heard of gaining spl with this design or using a hole in a plate ?
Posts: 335 | From: utah | Registered: Sep 1999
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posted
The plate mentioned in the article works kinda like a loading board but is a different animal. I don't know the reason for the 'hole' but if a person uses a plate or cone shaped object in front of the cone you can vary low frequency extension by how close or far you place the plate from the cone. This is similar to the phase plug on most tweeters. The tradeoff is always SPL so I don't know how the guy in the mag claims he gained BOTH?
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And that's the bottom line, cuz: LORD DUKK SAYS SO!
The Big Show The Dukk says: Know your bass: PORT your damn box!! Have HoleSaw, Will Travel!
posted
Yeah, I saw that issue, and the pic. It did have a hole in the corner for air movement. It looked like a pretty simple design, just a plexi cover over the subs cone. The editor said if he had any doubts he didn't any more, so it must work and sound good. My only question is how much it will muffle the sound.
[This message has been edited by BIGBLUE (edited 01-13-2000).]
posted
Well I have also seen what you are saying. Never seen it with the hole in the plate. But a plate mounted a few inches above the sub to load it up.
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