Hey Everyone, It's been a long time since I was last on the forum, but duty calls and I had to go away for awhile, but I am glad to be back safe and sound and able to get on the forum again. But anyways with all that said I am jumping right in the pool and asking for help. When I got back a buddy of mine knows that I am dabbling in the car stereo installation and enclosure fabrication business and asked me to build him an enclosure for his sub, so i am going to build him an enclosure. Now I have ran into a problem, what dimensions should the enclosure be. I tried looking up info on the sub but cannot find any. The sub is a ALPINE SWS 3046, its a 12" sub. I suspect that it is probably an older model, but not real sure, as I am kinda young in the audio world. I don't know if this helps any the amp he wil be using to power the sub is a KENWOOD KAC 719. well thats it for no hope I gave enough info if not please tell me what other info you need and I' try to get it. As always thanx for your help and if anybody needs any help please let me know I am always willing to help with what I can.
Crash COFFEEIDEASMILEUSFLAG
Replies (13)
swez on 04/15/2004 10:10:21
Hi Crash... good to have you back!
Seems like an older Alpine sub....(not in main Alpine sub listings anymore. But since it is SWS series, you can use a sealed enclosure between 0.88 - 1.25 cf (internal) with good results. Are you sure of that Sub model #?
The smaller side of the spec (good for Rock/techno) nets nore power handling and less deep bass extension. The larger side of the spec is better for deep low bass with a bit less power needed before the sub goes past X-max. To be on the safe side, a box of 1.0 cf is a good mix for both power and good bass extension.
That amp must be an older unit as well? It looks like #10 gage wire is needed. So, probably 75 x 2 to 100 x 2 range RMS. (fused at 25 - 30 amps?)
Swez
saintanddolphin on 04/15/2004 10:15:07
The model # of this sub is not listed in the archives of the alpine website...It is either too old or it is not the right model#..the site does have SWS-3045f and SWS-3045.The F in the model # indicates a free-air sub...Since the Thiel Small Parameters vary greatly between theSWS-3045 and the next sub in that series the SWS-3047 it is important to know more information about your particular sub.You also need to think about how you want the sub to sound.Is your friend want good sound guality(SQ) or is he a bass head and just wants loud bass(SPL) or a good mix of both(SQ/SPL).You can go herehttp://www.stylestandard.net/oswego/Doc/0/0E7K49RE5AAK94PKNVH0KGH7C6/SWS-3045.pdf and here http://www.stylestandard.net/oswego/Doc/0/53GKUA36BQUKT3K2ECT0JUL89A/SWS-3047.pdf and look @ the front of the sub of each and see if either of these looks like the one you have and that will get us a lot closer.The subs listed are 100w rms subs..May not be what your friend will be expecting as far as performance goes..I am not knocking his equipment but he would probably be more satisfied with a higher rms speaker.Alpine makes a very good sub line in there newer type r series..If he wants to keep this sub check the pdf's i have given you above and let us know what one it is.The amp you mentioned would be fine for a 100w sub.It is rated @ 150w rms x 1 @ 4ohms and its class D.A good choice if the sub is indeed 100w rms.
Mike COFFEE
PS Welcome back home
saintanddolphin on 04/15/2004 10:17:32
Sorry Swez,it loks like we were posting @ the same time
Mike
saintanddolphin on 04/15/2004 10:29:49
you are @ it early this morning....
swez on 04/15/2004 15:08:59
Yep.. did not sleep much last night.... 3:00 AM before I could finally wind down enough to dose off.
Good research on those items dude... pretty soon, you can have my chair on the board... j/k... you'll have to pry me out of it with a tow truck.. hehe
Swez
CrashMechanic on 04/16/2004 05:53:44
well to answer your question yes I am sure of the sub model, but it does look like the SWS 3045 model in the pdf that you posted. Also some more helpful info from looking on the back of the sub again it is a 300watt peak 100watt RMS sub. Don't worry no offense taken about it not being what he might expect because he only wants something to get by with until he gets back to the states, he feels that there really isn't a point to dump a bunch of money into a system right now because he will only be stationed here in Japan for a few years. He isn't like me, I have to have bump wherever I go unless I absolutely can't. Well anyways gotta go hope the info is good enough if not let me know. Once again thanx
CrashUSFLAGSMILE
CrashMechanic on 04/16/2004 05:55:21
oh yeah I also meant to tell you that the amp is fused at 30amps
CrashUSFLAG
swez on 04/16/2004 06:50:10
Use a #8 wiring kit on this one so if he decides to upgrade to a larger amp later, won't have to re-wire. The #8 is good up to 50 amps of current.
Swez
saintanddolphin on 04/16/2004 15:44:19
When laying out a system, you need to decide what type of enclosure to use. No enclosure is magic.
A sealed enclosure will be the smallest (for a given response shape) and will have good low frequency extension but may not have the best low frequency extension. If space is limited, this may be your best choice.
A ported enclosure will generally have a better low frequency extension for a given response shape (alignment) but would require a larger enclosure. If you made the enclosure as small as the sealed enclosure but ported it to gain the low frequency response, the output would deviate from the desired flat response.
A bandpass enclosure can sound good and give you a flat response but most of the generic bandpass enclosures are not designed for a flat response. They are designed to impress you in the stores. This means that they are built to produce a large peak at some frequency near 60hz. These enclosures will work well with something like rap music but generally won't sound good with other types of music. If you use a bandpass enclosure, it should be designed specifically for your speakers.
If you're building your first system, I'd recommend a sealed enclosure. It is the simplest enclosure and will be the easiest to get right. A sealed enclosure only needs to be the right size and well sealed. Alright... Enough of my opinions. Move on to the next section.
--------------------------------------------------------------------------------
Calculating Speaker Enclosure Volume
As you already know, for speakers (especially woofers) to work properly, they must be in the proper size enclosure. The manufacturer can give you the required enclosure volume but can't give the exact dimensions of an enclosure that will work in all vehicles. So that you can build an enclosure of the proper size for your vehicle, this page will explain how you calculate the total volume of the enclosure.
Magic number:
OK... It's not magic but the number is 1728. If you forget it, just remember that the number is 12 inches * 12 inches * 12 inches. 12*12*12=1728.
Square or Rectangular Enclosures:
These boxes are the easiest to calculate the internal volume. You simply measure the height, width and depth (in inches), multiply them together and then divide that number by 1728. If the box has internal measurements of 6" high*18" wide*12" deep then the volume of the box is 1296/1728=.75 ft^3.
This is an idea of what goes into planning the construction and installation of any sub. You can find the above information as well as some very detailed information on any car audio topic @ : http://www.bcae1.com/.This site also has a enclosure calculater that all you have to do is punch in a few measurements and viola it will give internal dimensions for specific application.
I think that we should try to shoot for box dimensions close to the Alpine specs: 2.25 cu.ft. is recomended for a neutral response.You are going to use "polyfill"(you can buy it @ Walmart or any fabric store) to line the walls of the inside of the box, we can cut that box size down to about 1.7cu.ft.
When building a box other variables come into play:Wood thickness,type of wood,amont of pollyfill.
The wood thickness should be 3/4" and the type pf wood should be MDF (Medium Density Fiberboard).We are also going to line the inner walls with 25-30oz. of pollyfill(I use staples to secure it to the walls because there is nothing worse than getting the box playing and hearing the pollyfill screeching on the back of the cone.Some people use hot glue and others just "stuff" it in there).
I dont know how much room is in this car(in fact ive never even heard of it) so giving you actual dimensions would be a crap shoot.I can tell you that a 14.5" rectangular box(inside deminsions of each piece, will net you about 1.79cu.ft. of internal volume.You will need to add 11/2" to the top and bottom so as to account for the 3/4" thickness of the wood.
If you can give us some measurements from the car we could do a lot better for box deminsions and even try to make it a wedge shape.This would cut down on "Backlash"(sound waves reverberating directly back to the cone).I prefer a wedge for a sealed enclosure.
If you cant get started with this way over-blown explaination,give us a little more info on the inside of the vehicle.
Good luck.
Mike COFFEE
PS As you can probably tell I dont have jack to do today..sorry if that was way too much
swez on 04/16/2004 19:30:44
LOL good job Mike!
I stand mute!
Swez
CrashMechanic on 04/16/2004 20:29:44
Holy Macaral, very well explained. I fully understand what you are saying, but have some ideas. First let me tell you about the car, it seems I forgot to mention it before. The car is a 91 Civic(Jap Spec)which means its probably a 92 or 93 Civic, I don't have measurments yet but come monday I will take measurments so I know what I have to work with. Now here is my thought, since he doesn't want extreme SPL or extreme SQ, I figure I would go with a little boomy but with a tad SQ, so I figure 1.5cf internal before polyfill. How does that sound. Well, I will get the Space Available Dimensions on monday, and let you know. Thanx
CrashUSFLAG
saintanddolphin on 04/16/2004 21:33:38
I thought that might be a little over the top but I am glad you understand it.Although 1.7cu.ft. is an optimal neutral number, thats just what it is ,a number.Thats the beauty of a sealed enclosure,you have room for compromise or error.
You can use 1.5cu.ft and see what happens.There are no guaranties about either because it is impossible to know how the acoustic imaging within the car will affect total sq/spl.
Try using the same amount of pollyfill.If it sounds to boomy you can add a little more.
We are glad to help and let us know those other dimensions as we will try to get it done.
Mike COFFEE
PS thanks swez! It means alot coming from you.
CrashMechanic on 04/19/2004 06:46:53
heyreal quick let me tell you those measurements, my friends trunk measurements are H19"xW42"xTD30"xBD35". Hope thats good enough, and I also stand corrected that it is a 95 Civic(J-Spec) wich means it's probably equal to a 96 Civic(US spec). Now, I went to that site that you suggested Mike and it was very helpful, I have figured out my measurements for a box that will have 1.53cf internal, I will try that out and post back on how it works out, but might be awhile before I finish, I like to take my time and do a good job.
Thanx Guys
CrashUSFLAG
P.S. Lokks like I will be frequenly visiting that site Mike mentioned so that I can read everything there, who know I might even learn something hehehe.
Crash COFFEEIDEASMILEUSFLAG
Replies (13)
swez on 04/15/2004 10:10:21
Hi Crash... good to have you back!
Seems like an older Alpine sub....(not in main Alpine sub listings anymore. But since it is SWS series, you can use a sealed enclosure between 0.88 - 1.25 cf (internal) with good results. Are you sure of that Sub model #?
The smaller side of the spec (good for Rock/techno) nets nore power handling and less deep bass extension. The larger side of the spec is better for deep low bass with a bit less power needed before the sub goes past X-max. To be on the safe side, a box of 1.0 cf is a good mix for both power and good bass extension.
That amp must be an older unit as well? It looks like #10 gage wire is needed. So, probably 75 x 2 to 100 x 2 range RMS. (fused at 25 - 30 amps?)
Swez
saintanddolphin on 04/15/2004 10:15:07
The model # of this sub is not listed in the archives of the alpine website...It is either too old or it is not the right model#..the site does have SWS-3045f and SWS-3045.The F in the model # indicates a free-air sub...Since the Thiel Small Parameters vary greatly between theSWS-3045 and the next sub in that series the SWS-3047 it is important to know more information about your particular sub.You also need to think about how you want the sub to sound.Is your friend want good sound guality(SQ) or is he a bass head and just wants loud bass(SPL) or a good mix of both(SQ/SPL).You can go herehttp://www.stylestandard.net/oswego/Doc/0/0E7K49RE5AAK94PKNVH0KGH7C6/SWS-3045.pdf and here http://www.stylestandard.net/oswego/Doc/0/53GKUA36BQUKT3K2ECT0JUL89A/SWS-3047.pdf and look @ the front of the sub of each and see if either of these looks like the one you have and that will get us a lot closer.The subs listed are 100w rms subs..May not be what your friend will be expecting as far as performance goes..I am not knocking his equipment but he would probably be more satisfied with a higher rms speaker.Alpine makes a very good sub line in there newer type r series..If he wants to keep this sub check the pdf's i have given you above and let us know what one it is.The amp you mentioned would be fine for a 100w sub.It is rated @ 150w rms x 1 @ 4ohms and its class D.A good choice if the sub is indeed 100w rms.
Mike COFFEE
PS Welcome back home
saintanddolphin on 04/15/2004 10:17:32
Sorry Swez,it loks like we were posting @ the same time
Mike
saintanddolphin on 04/15/2004 10:29:49
you are @ it early this morning....
swez on 04/15/2004 15:08:59
Yep.. did not sleep much last night.... 3:00 AM before I could finally wind down enough to dose off.
Good research on those items dude... pretty soon, you can have my chair on the board... j/k... you'll have to pry me out of it with a tow truck.. hehe
Swez
CrashMechanic on 04/16/2004 05:53:44
well to answer your question yes I am sure of the sub model, but it does look like the SWS 3045 model in the pdf that you posted. Also some more helpful info from looking on the back of the sub again it is a 300watt peak 100watt RMS sub. Don't worry no offense taken about it not being what he might expect because he only wants something to get by with until he gets back to the states, he feels that there really isn't a point to dump a bunch of money into a system right now because he will only be stationed here in Japan for a few years. He isn't like me, I have to have bump wherever I go unless I absolutely can't. Well anyways gotta go hope the info is good enough if not let me know. Once again thanx
CrashUSFLAGSMILE
CrashMechanic on 04/16/2004 05:55:21
oh yeah I also meant to tell you that the amp is fused at 30amps
CrashUSFLAG
swez on 04/16/2004 06:50:10
Use a #8 wiring kit on this one so if he decides to upgrade to a larger amp later, won't have to re-wire. The #8 is good up to 50 amps of current.
Swez
saintanddolphin on 04/16/2004 15:44:19
When laying out a system, you need to decide what type of enclosure to use. No enclosure is magic.
A sealed enclosure will be the smallest (for a given response shape) and will have good low frequency extension but may not have the best low frequency extension. If space is limited, this may be your best choice.
A ported enclosure will generally have a better low frequency extension for a given response shape (alignment) but would require a larger enclosure. If you made the enclosure as small as the sealed enclosure but ported it to gain the low frequency response, the output would deviate from the desired flat response.
A bandpass enclosure can sound good and give you a flat response but most of the generic bandpass enclosures are not designed for a flat response. They are designed to impress you in the stores. This means that they are built to produce a large peak at some frequency near 60hz. These enclosures will work well with something like rap music but generally won't sound good with other types of music. If you use a bandpass enclosure, it should be designed specifically for your speakers.
If you're building your first system, I'd recommend a sealed enclosure. It is the simplest enclosure and will be the easiest to get right. A sealed enclosure only needs to be the right size and well sealed. Alright... Enough of my opinions. Move on to the next section.
--------------------------------------------------------------------------------
Calculating Speaker Enclosure Volume
As you already know, for speakers (especially woofers) to work properly, they must be in the proper size enclosure. The manufacturer can give you the required enclosure volume but can't give the exact dimensions of an enclosure that will work in all vehicles. So that you can build an enclosure of the proper size for your vehicle, this page will explain how you calculate the total volume of the enclosure.
Magic number:
OK... It's not magic but the number is 1728. If you forget it, just remember that the number is 12 inches * 12 inches * 12 inches. 12*12*12=1728.
Square or Rectangular Enclosures:
These boxes are the easiest to calculate the internal volume. You simply measure the height, width and depth (in inches), multiply them together and then divide that number by 1728. If the box has internal measurements of 6" high*18" wide*12" deep then the volume of the box is 1296/1728=.75 ft^3.
This is an idea of what goes into planning the construction and installation of any sub. You can find the above information as well as some very detailed information on any car audio topic @ : http://www.bcae1.com/.This site also has a enclosure calculater that all you have to do is punch in a few measurements and viola it will give internal dimensions for specific application.
I think that we should try to shoot for box dimensions close to the Alpine specs: 2.25 cu.ft. is recomended for a neutral response.You are going to use "polyfill"(you can buy it @ Walmart or any fabric store) to line the walls of the inside of the box, we can cut that box size down to about 1.7cu.ft.
When building a box other variables come into play:Wood thickness,type of wood,amont of pollyfill.
The wood thickness should be 3/4" and the type pf wood should be MDF (Medium Density Fiberboard).We are also going to line the inner walls with 25-30oz. of pollyfill(I use staples to secure it to the walls because there is nothing worse than getting the box playing and hearing the pollyfill screeching on the back of the cone.Some people use hot glue and others just "stuff" it in there).
I dont know how much room is in this car(in fact ive never even heard of it) so giving you actual dimensions would be a crap shoot.I can tell you that a 14.5" rectangular box(inside deminsions of each piece, will net you about 1.79cu.ft. of internal volume.You will need to add 11/2" to the top and bottom so as to account for the 3/4" thickness of the wood.
If you can give us some measurements from the car we could do a lot better for box deminsions and even try to make it a wedge shape.This would cut down on "Backlash"(sound waves reverberating directly back to the cone).I prefer a wedge for a sealed enclosure.
If you cant get started with this way over-blown explaination,give us a little more info on the inside of the vehicle.
Good luck.
Mike COFFEE
PS As you can probably tell I dont have jack to do today..sorry if that was way too much
swez on 04/16/2004 19:30:44
LOL good job Mike!
I stand mute!
Swez
CrashMechanic on 04/16/2004 20:29:44
Holy Macaral, very well explained. I fully understand what you are saying, but have some ideas. First let me tell you about the car, it seems I forgot to mention it before. The car is a 91 Civic(Jap Spec)which means its probably a 92 or 93 Civic, I don't have measurments yet but come monday I will take measurments so I know what I have to work with. Now here is my thought, since he doesn't want extreme SPL or extreme SQ, I figure I would go with a little boomy but with a tad SQ, so I figure 1.5cf internal before polyfill. How does that sound. Well, I will get the Space Available Dimensions on monday, and let you know. Thanx
CrashUSFLAG
saintanddolphin on 04/16/2004 21:33:38
I thought that might be a little over the top but I am glad you understand it.Although 1.7cu.ft. is an optimal neutral number, thats just what it is ,a number.Thats the beauty of a sealed enclosure,you have room for compromise or error.
You can use 1.5cu.ft and see what happens.There are no guaranties about either because it is impossible to know how the acoustic imaging within the car will affect total sq/spl.
Try using the same amount of pollyfill.If it sounds to boomy you can add a little more.
We are glad to help and let us know those other dimensions as we will try to get it done.
Mike COFFEE
PS thanks swez! It means alot coming from you.
CrashMechanic on 04/19/2004 06:46:53
heyreal quick let me tell you those measurements, my friends trunk measurements are H19"xW42"xTD30"xBD35". Hope thats good enough, and I also stand corrected that it is a 95 Civic(J-Spec) wich means it's probably equal to a 96 Civic(US spec). Now, I went to that site that you suggested Mike and it was very helpful, I have figured out my measurements for a box that will have 1.53cf internal, I will try that out and post back on how it works out, but might be awhile before I finish, I like to take my time and do a good job.
Thanx Guys
CrashUSFLAG
P.S. Lokks like I will be frequenly visiting that site Mike mentioned so that I can read everything there, who know I might even learn something hehehe.
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