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The mouse needs a cone at the moment, and the 15W3 is a useful second driver for those just in case times.
I've investigated a few options, the Hordans seem very well designed.
It can be scary how much a complete set of speakers can cost though when you add it up.
JX92S *2 about £180 2 OZ audio Matrix 10 about £350 High quality wood About £80 (or more) Ports, Caps/coils about £20 --- £630 You can pick up some nice B&W speakers for about that much second hand. Of course it'll be a different sound.
Colin
-------------------- *hmm need to think of a new sig*
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[QUOTE]Originally posted by Mouser: [QB]The mouse needs a cone at the moment, and the 15W3 is a useful second driver for those just in case times.
Thats the problem with horns; they drop like **** below the Fb, and setting the subsonic filter is very important.
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Yeah I know who you are from talkaudio because I recognise the sig, just wanted to make sure it wasn't just a copy. As far as names go I'll remember next time I see a post by you on talkaudio... can't be bothered to think right now.
I shortened it to try to raise the frequency to play at for peak SPL... it was more a ported box than a horn, although the hatch effectively made it a lot longer and larger...
Colin
-------------------- *hmm need to think of a new sig*
btw - what do you all think would be a good box size for the old rockford he2 8" series? rfp 2208 and the damn rockford site isn't cooperating right now....
I was thinking about 1.2 cubes per 8, but wasnt too sure thanks, Steve
-------------------- 2005 Florida Street C Champion 2004 SBN Street C Champion 2004 SBN IDBL No Wall Champion 2003 NOPI Nats Street B Champion
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Steve, making an ABC box for an 8" sub is going to be tricky due to the difficulty involved in fitting the ports in unless you go for very small ports.
Chris (Davitch(Bass Freak)) yeah I remember now you say. There aren't too many bass heads on talkaudio anyway.
Colin
-------------------- *hmm need to think of a new sig*
quote:Originally posted by Bass Freak: A REAL bass horn would have been about 20 ft long for that 15!
In my opinion, this statement gives the impression that a larger driver requires a longer horn. I may be reading it wrong.
Actually, the larger the driver, the shorter the horn. A horn's mouth area is relative to its cutoff frequency, independent of driver size. The horn will flare at a rate determined by horn type (Tratrix/exponential/etc.).
Imagine for a minute a large funnel that tapers down to an eydropper sized hole. It has a predetermined flare rate. It is tuned for a specific frequency range. Drop an ear-bud size driver in there. Where it stops is where the throat starts. The horns length is from there to the mouth (large end) measured down the center of the horn.
Now drop a 3" boombox speaker in the funnel. It didn't drop as far, but the tuning frequency of the horn is the same even though the driver is larger. The difference between the two horns is that the one with the larger driver is shorter (you don't need anything horn-wise on the back side of the driver)
Of course efficiencies, response curves, etc., for each driver above are assumed identical for simplicity to illustrate a point. That is: the smaller your driver, the longer your horn.
As for the 15" horn, you could get a nice exponential bass horn tuned to 32Hz in about 6'. Of course that's taking into account that in a car the horn will not be firing into all 8 quadrants. Fire into only one quadrant and you can reduce the size by a factor of 8. Nice.
Now this is still a rather large horn! With rough math, you're looking at a mouth with 1810 sq. in. or so!
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You're right. This does give a false impression of horns.
It was actually meant to be an exaggeration...and I was thinking more along the lines of hyperbolic horns as opposed to exponentials...
At the moment I'm covered in fibreglass and MDF dust, but later on when I finish work, I'll post a more thorough reply, as I wouldn't mind discussing horns with you in more detail.
horns then-for frequencies below 300hz, i wouldn't use tractrix designs. hyperbolic or h/e would be the only thing i'd use.
finding the right driver helps, ie low qts, high fs (qts/fs=greater than 120 for a suitable driver), or finding a proven compression driver.
typically it is the mouth of the horn which deems it impractial, even though bass horns are usually folded. assuming an SF of one, the horns mouth must be equal to one wavelength at the flare frequency, but i would always use an SF of 8 for bass for obvious reasons.
crap-the boss is shouting for me to do some work-laters!!
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Has anyone made an ABC box for a (1) 15" HCCA? Just wondering what kinda numbers to expect, using an Orion 2250 AMP.
-------------------- Out of jail and ready to crack some skulls 2000 Mustang 3.8 5 speed NecVox DA7169 7" in dash color monitor DVA 310x(DVD,CD player) DA 230I (AM, FM, Tuner) Davinci 15 No amp right now, I had to sell it to pay some bills. highs and Mids MB Quartz Posts: 164 | From: San Antonio, TX | Registered: Nov 2001
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