Author
Topic: Excursion formula please...
Does anyone know the formula for expressing cone excursion?I know some box programs calculate this, and I'm assuming it's a formula based around the Xmax figure.
Anyone?
TIA
Bass Freak
Senior Member
posted 01-03-2002 04:14 AM
Does anyone know the formula for expressing cone excursion?I know some box programs calculate this, and I'm assuming it's a formula based around the Xmax figure.
Anyone?
TIA
Posts: 712 | From: UK | Registered: Sep 2001
| IP: Logged |
It's also based around box type, size, and other various woofer parameters. Your best bet is to use a program, a formula would give you a single value and that's not much use.
emu
Senior Member
posted 01-03-2002 04:32 AM
It's also based around box type, size, and other various woofer parameters. Your best bet is to use a program, a formula would give you a single value and that's not much use.
Posts: 768 | From: Ottawa, On, Canada | Registered: May 2000
| IP: Logged |
You can get the theoretical displacement by using this formula:pi x r^2 x x-max
r is one-half of the diameter of the subwoofer.
For a 12 inch sub with 1.0 inches peak-to-peak excursion the theoretical displacement is:
pi x 6.0 x 6.0 x 1.0 = 113.04 in^3
PBCrunch
New Member
posted 01-03-2002 03:07 PM
You can get the theoretical displacement by using this formula:pi x r^2 x x-max
r is one-half of the diameter of the subwoofer.
For a 12 inch sub with 1.0 inches peak-to-peak excursion the theoretical displacement is:
pi x 6.0 x 6.0 x 1.0 = 113.04 in^3
Posts: 42 | From: Omaha, Nebraska, USA | Registered: Jul 2001
| IP: Logged |
quote: www.google.com or you could just get bassbox pro/lite or leap or temrpro or...
I use basbox pro now and it's nice
[ 01-03-2002: Message edited by: Mouser ]
Jammy bugger!!!
Mine's going to have to wait, Col.
Gotta service the motor.
So there's no way I can use a formula to tell me how much excursion the sub will have at a certain frequency?
Does anyone know of a program that does this but doesn't cost buckage?
thanks
Bass Freak
Senior Member
posted 01-04-2002 02:59 AM
quote: www.google.com or you could just get bassbox pro/lite or leap or temrpro or...
I use basbox pro now and it's nice
[ 01-03-2002: Message edited by: Mouser ]
Jammy bugger!!!
Mine's going to have to wait, Col.
Gotta service the motor.
So there's no way I can use a formula to tell me how much excursion the sub will have at a certain frequency?
Does anyone know of a program that does this but doesn't cost buckage?
thanks
Posts: 712 | From: UK | Registered: Sep 2001
| IP: Logged |
quote: Most registered box design software can do this.
Yeah, shame mine isn't...
Can't wait to get BassBox 6 Pro. Mind if I ask what you use?
Oh, nice site btw. Currently building my first abc for my 12, and your site was real useful.
Bass Freak
Senior Member
posted 01-04-2002 08:06 PM
quote: Most registered box design software can do this.
Yeah, shame mine isn't...
Can't wait to get BassBox 6 Pro. Mind if I ask what you use?
Oh, nice site btw. Currently building my first abc for my 12, and your site was real useful.
Posts: 712 | From: UK | Registered: Sep 2001
| IP: Logged |
I've used bassbox lite, had borrowed LEAP for a few months from a friend(can you say sweetness?). I mostly use a few qbasic programs I've made, as well as winISD for quick referencing.
emu
Senior Member
posted 01-05-2002 06:19 AM
I've used bassbox lite, had borrowed LEAP for a few months from a friend(can you say sweetness?). I mostly use a few qbasic programs I've made, as well as winISD for quick referencing.
Posts: 768 | From: Ottawa, On, Canada | Registered: May 2000
| IP: Logged |
pi x 6.0 x 6.0 x 1.0 = 113.04 in^3 you take dia of cone + 1/3 surround and cut that in 1/2 then pi*R^2
Dia of sub 12.5" - 1.25" (mounting flange area) - 2" (assuming 3" surround total)leaves 9.25" of useable cone area.
9.25/2=4.625.. pi*(4.625^2)= 67.200 sq in.
using 12" for a 12" sub is IASCA's way of doing speaker area for contests it has nothing to do with displacements.
Iboomalot
Senior Member
posted 01-05-2002 08:45 AM
pi x 6.0 x 6.0 x 1.0 = 113.04 in^3 you take dia of cone + 1/3 surround and cut that in 1/2 then pi*R^2
Dia of sub 12.5" - 1.25" (mounting flange area) - 2" (assuming 3" surround total)leaves 9.25" of useable cone area.
9.25/2=4.625.. pi*(4.625^2)= 67.200 sq in.
using 12" for a 12" sub is IASCA's way of doing speaker area for contests it has nothing to do with displacements.
Posts: 3071 | From: Okla USA | Registered: May 1999
| IP: Logged |
quote: pi x 6.0 x 6.0 x 1.0 = 113.04 in^3 you take dia of cone + 1/3 surround and cut that in 1/2 then pi*R^2
Dia of sub 12.5" - 1.25" (mounting flange area) - 2" (assuming 3" surround total)leaves 9.25" of useable cone area.
9.25/2=4.625.. pi*(4.625^2)= 67.200 sq in.
using 12" for a 12" sub is IASCA's way of doing speaker area for contests it has nothing to do with displacements.
Thanks but that still doesn't help.
I need to know excursion vs frequency for a given input power.
I need to know how much power the woofer will have to recieve at a given frequency to make it over excurt...so that I can avoid it but tune the box for it's maximum safe gain.
There must be a free program or a formula for this?
emu, which do you prefer: LEAP or BassBox?
Also, is TermLab really worth the money?
Thanks guys
Bass Freak
Senior Member
posted 01-05-2002 04:37 PM
quote: pi x 6.0 x 6.0 x 1.0 = 113.04 in^3 you take dia of cone + 1/3 surround and cut that in 1/2 then pi*R^2
Dia of sub 12.5" - 1.25" (mounting flange area) - 2" (assuming 3" surround total)leaves 9.25" of useable cone area.
9.25/2=4.625.. pi*(4.625^2)= 67.200 sq in.
using 12" for a 12" sub is IASCA's way of doing speaker area for contests it has nothing to do with displacements.
Thanks but that still doesn't help.
I need to know excursion vs frequency for a given input power.
I need to know how much power the woofer will have to recieve at a given frequency to make it over excurt...so that I can avoid it but tune the box for it's maximum safe gain.
There must be a free program or a formula for this?
emu, which do you prefer: LEAP or BassBox?
Also, is TermLab really worth the money?
Thanks guys
Posts: 712 | From: UK | Registered: Sep 2001
| IP: Logged |
Bassbox was actually quite nice, but LEAP is incredible. The price is also incredible. I only managed to borrow a copy for a while. BassboxPro is extremely niceI've never tried termlab.
E-mail me, I have a program that can help you learn, with a few tutorials maybe.
emu
Senior Member
posted 01-05-2002 05:06 PM
Bassbox was actually quite nice, but LEAP is incredible. The price is also incredible. I only managed to borrow a copy for a while. BassboxPro is extremely niceI've never tried termlab.
E-mail me, I have a program that can help you learn, with a few tutorials maybe.
Posts: 768 | From: Ottawa, On, Canada | Registered: May 2000
| IP: Logged |
(c) 1996-2007 WHE Inc, Carson City Nevada, USA
Infopop Corporation
Printer-friendly view of this topic