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murph
07-10-2012, 02:44 AM
I know that the bigger the ratio the better but, when does this draw the line. Also on the sealed half what is recommended to go with the factory recommendation or what? Any other info that you may want to enlighten is appreciated.

VisceralSound
07-10-2012, 02:45 AM
Moble Enclosurs

plantinseeds
07-10-2012, 02:56 AM
Moble Enclosurs

When in doubt, call upon Moble Enclosurs!

and it's your*

murph
07-10-2012, 04:08 AM
When in doubt, call upon Moble Enclosurs!

and it's your*

There are many box builders on here with knowledge.

RSDXzec
07-10-2012, 04:38 AM
When in doubt, call upon Moble Enclosurs!

and it's your*

completely agree with this lol.

also, if you want a quick answer you can run a simulation on winisd to get an idea, but for a detailed response wait for moble enclosures.
last I heard he was pretty busy with box designs so might take a couple days but worth the wait ;)

murph
07-10-2012, 04:43 AM
completely agree with this lol.

also, if you want a quick answer you can run a simulation on winisd to get an idea, but for a detailed response wait for moble enclosures.
last I heard he was pretty busy with box designs so might take a couple days but worth the wait ;)

I am looking for different facts no specific to an enclosure I am designing but, in general. Again there are many box builders on here with much knowledge.

CAT MAN
07-10-2012, 04:58 AM
sealed half is sometimes to spec. other times it could be cut in half. all depends. i draw the line at 5:1 for daily.

murph
07-10-2012, 05:02 AM
sealed half is sometimes to spec. other times it could be cut in half. all depends. i draw the line at 5:1 for daily.

What effect does no going to spec have on the performance? When looking for the best low end response I would assume cutting it in half would not be good.

mlstrass
07-10-2012, 06:51 AM
power handling also plays into the sealed side. there's a pretty good thread on caco about 4th orders.

I'm just finishing my first one ever, for 10 18's. Pretty happy with it so far....

madcad95
07-10-2012, 08:47 AM
I was told the sealed side should be smaller if you plan on big power but for low to moderate power you can go bigger I have built a couple in the past and they either sounded way to peaky or they sounded good but would eat woofers lol.

BIGJEFF64
07-10-2012, 09:36 AM
depends on what ur requirements are for. the general rule of thumb is 3:1 but i have seen 1.5 :1 work pretty well but i havent gone over 3:1 before

plantinseeds
07-10-2012, 01:53 PM
There are many box builders on here with knowledge.

Sorry, I totally agree haha.

murph
07-10-2012, 04:20 PM
Yeah I know the ideal ratio is 3:1 and I plan to get as close to that as possible.

double 07
07-10-2012, 04:56 PM
My suggestion would be to keep the sealed chamber at spec of sub or just below it unless you enjoy buying subs.....i found this out the hard way......lol

murph
07-10-2012, 05:02 PM
My suggestion would be to keep the sealed chamber at spec of sub or just below it unless you enjoy buying subs.....i found this out the hard way......lol

Ok so in a trunk would there be any benefit facing towards the trunk vs. aiming it in the cabin. (not sealed off) Does port size play a large factor in the performance the box?

double 07
07-10-2012, 05:08 PM
If it was mine i would aim it towards the rear of the car and use the same spec for the ported section that you would if it were a normal ported enclosure. I would tune my ported section in the range of 43-45 because the sealed chamber will handle the lows....

murph
07-10-2012, 08:46 PM
Up so which way should it be faced in the trunk?

double 07
07-10-2012, 08:52 PM
I don't think it will work very well facing forward UNLESS you seal it off from the back side......Facing the rear will work as long as the BOX isn't choking off the space allowing air into the cabin....If your car's trunk has been sound deadend it will not rattle anymore with a rear facing 4th order than a regular ported box would rattle it without sound deadening material....

cyn
07-10-2012, 08:52 PM
I believe the one that is being done for my RE HC 12" is something like 2.5ish:1 ratio with a 10" port i'm going to blow throw my rear deck... all depends on what you want out of the box man... talk to Buck... Mobile... Ram... any of them

Kangaroux
07-10-2012, 08:54 PM
I believe the one that is being done for my RE HC 12" is something like 2.5ish:1 ratio with a 10" port i'm going to blow throw my rear deck... all depends on what you want out of the box man... talk to Buck... Mobile... Ram... any of them

That is WAYYYY too much port area man...it's going to be so peaky. An 8" for my single 12 was almost too much

cyn
07-10-2012, 08:55 PM
That is WAYYYY too much port area man...it's going to be so peaky. An 8" for my single 12 was almost too much

what was the tuning you had? I believe mine is going to be somewhere around 42-45ish... just waiting for it to be finished up..

mazdakid
07-10-2012, 09:13 PM
Built one for an sa8 a few weeks ago. 3:1 ratio with 2 4" aeros tuned to 52.
Kid really likes it and said its really nice for being on his kicker 4 channel.
Ports facing back is loudest in his car with the little box.

murph
07-10-2012, 09:14 PM
I don't think it will work very well facing forward UNLESS you seal it off from the back side......Facing the rear will work as long as the BOX isn't choking off the space allowing air into the cabin....If your car's trunk has been sound deadend it will not rattle anymore with a rear facing 4th order than a regular ported box would rattle it without sound deadening material....

Exactly why he confused me. I would give the port plenty of room to breathe and my trunk ofc is deadened.

Moble Enclosurs
07-10-2012, 11:15 PM
There is no real general ratio for 4th orders. There are too many variables involved in the design. 4th orders differ from other designs (even 6th) in that they naturally have a higher efficiency at a specific frequency. We all know that, but what many done realize is that regardless of the chamber volume, due to the on and off response of a 4th order, naturally, the vehicle makes the final determination in how it will sound. I will rarely design a 4th without the vehicle in mind. If someone asks for a basic design without vehicle calculations, I tend to draw myself to a more simplified physical form and guarantee proper output performance, such as that with tlines and BRs. SO, the 3:1, 1.5: etc all has its own effect on the performance, just as it should. Sometimes minimal, sometimes COMPLETELY different sounds can be heard. The most important part of the 4th order lies in the control of the driver. As mentioned above, using a sealed box recommendation volume for the sealed area, then another mentioned using a standard ported calculation for the ported section......these are great ideas to follow if you do not figure for every factor and just want to design something from simplistic means of calculation.
I personally do not use a general ratio. I let the sub tell me what it wants. Without regard to dimensional space limitations, I also do not trend the "port is to big" quote either, as the port cannot ever be to big, but we ARE limited on space, so that does put some limitations on that as well. But I always go with an optimum port area UNLESS I do not have the room to use it, then go with my calculated minimum area and use a larger compression volume. But in doing this, again you maintain control. Control is key in 4th orders, and without knowing a specific ratio for your subs, its a toss up. There are many people that will design and build many of these time after time to get it right, and those will argue with me that sometimes that works best. But to not waste your time and money, you have to involve all aspects of the design to come up with any volumes to utilize effectively from the start in these designs.
The best idea that was given thus far was whoever said use the conventional ported recommended specs for the ported side. This will ensure at the least that some control is given BEFORE the sealed side is even figured in. The sealed side is, and can be actually tougher to design sometimes as the cross-sectional area may limit the depth of the sealed area for excursion capabilities based on a specific volume, so I guess as mentioned, the recommended sealed volume can be utilized for this part, but I would say try to stay UNDER that at the most. I believe that is what was said from the other member as well. Two of the best, "generalized" comments on 4th orders you can use thus far. That all considered, you should be very close to having a great response with those two design ideas considered within the same design.

Just remember, you will never be able to make the box too big as long as all aspects of the design are done right. You can however make it too small, so make sure to give enough room for it, or output will suffer greatly even if you never mechanically blow the sub(s). Mechanical limits may force some to exceed thermal ones without knowing it. This is why I would never design a BP without proper calculation, but if you want generalized input from me, I would go with what the other two member mentioned that I recited here. Hope that helps

Moble Enclosurs
07-10-2012, 11:15 PM
There is no real general ratio for 4th orders. There are too many variables involved in the design. 4th orders differ from other designs (even 6th) in that they naturally have a higher efficiency at a specific frequency. We all know that, but what many done realize is that regardless of the chamber volume, due to the on and off response of a 4th order, naturally, the vehicle makes the final determination in how it will sound. I will rarely design a 4th without the vehicle in mind. If someone asks for a basic design without vehicle calculations, I tend to draw myself to a more simplified physical form and guarantee proper output performance, such as that with tlines and BRs. SO, the 3:1, 1.5: etc all has its own effect on the performance, just as it should. Sometimes minimal, sometimes COMPLETELY different sounds can be heard. The most important part of the 4th order lies in the control of the driver. As mentioned above, using a sealed box recommendation volume for the sealed area, then another mentioned using a standard ported calculation for the ported section......these are great ideas to follow if you do not figure for every factor and just want to design something from simplistic means of calculation.
I personally do not use a general ratio. I let the sub tell me what it wants. Without regard to dimensional space limitations, I also do not trend the "port is to big" quote either, as the port cannot ever be to big, but we ARE limited on space, so that does put some limitations on that as well. But I always go with an optimum port area UNLESS I do not have the room to use it, then go with my calculated minimum area and use a larger compression volume. But in doing this, again you maintain control. Control is key in 4th orders, and without knowing a specific ratio for your subs, its a toss up. There are many people that will design and build many of these time after time to get it right, and those will argue with me that sometimes that works best. But to not waste your time and money, you have to involve all aspects of the design to come up with any volumes to utilize effectively from the start in these designs.
The best idea that was given thus far was whoever said use the conventional ported recommended specs for the ported side. This will ensure at the least that some control is given BEFORE the sealed side is even figured in. The sealed side is, and can be actually tougher to design sometimes as the cross-sectional area may limit the depth of the sealed area for excursion capabilities based on a specific volume, so I guess as mentioned, the recommended sealed volume can be utilized for this part, but I would say try to stay UNDER that at the most. I believe that is what was said from the other member as well. Two of the best, "generalized" comments on 4th orders you can use thus far. That all considered, you should be very close to having a great response with those two design ideas considered within the same design.

Just remember, you will never be able to make the box too big as long as all aspects of the design are done right. You can however make it too small, so make sure to give enough room for it, or output will suffer greatly even if you never mechanically blow the sub(s). Mechanical limits may force some to exceed thermal ones without knowing it. This is why I would never design a BP without proper calculation, but if you want generalized input from me, I would go with what the other two member mentioned that I recited here. Hope that helps

Falcons
07-10-2012, 11:55 PM
There is no real general ratio for 4th orders. There are too many variables involved in the design. 4th orders differ from other designs (even 6th) in that they naturally have a higher efficiency at a specific frequency. We all know that, but what many done realize is that regardless of the chamber volume, due to the on and off response of a 4th order, naturally, the vehicle makes the final determination in how it will sound. I will rarely design a 4th without the vehicle in mind. If someone asks for a basic design without vehicle calculations, I tend to draw myself to a more simplified physical form and guarantee proper output performance, such as that with tlines and BRs. SO, the 3:1, 1.5: etc all has its own effect on the performance, just as it should. Sometimes minimal, sometimes COMPLETELY different sounds can be heard. The most important part of the 4th order lies in the control of the driver. As mentioned above, using a sealed box recommendation volume for the sealed area, then another mentioned using a standard ported calculation for the ported section......these are great ideas to follow if you do not figure for every factor and just want to design something from simplistic means of calculation.
I personally do not use a general ratio. I let the sub tell me what it wants. Without regard to dimensional space limitations, I also do not trend the "port is to big" quote either, as the port cannot ever be to big, but we ARE limited on space, so that does put some limitations on that as well. But I always go with an optimum port area UNLESS I do not have the room to use it, then go with my calculated minimum area and use a larger compression volume. But in doing this, again you maintain control. Control is key in 4th orders, and without knowing a specific ratio for your subs, its a toss up. There are many people that will design and build many of these time after time to get it right, and those will argue with me that sometimes that works best. But to not waste your time and money, you have to involve all aspects of the design to come up with any volumes to utilize effectively from the start in these designs.
The best idea that was given thus far was whoever said use the conventional ported recommended specs for the ported side. This will ensure at the least that some control is given BEFORE the sealed side is even figured in. The sealed side is, and can be actually tougher to design sometimes as the cross-sectional area may limit the depth of the sealed area for excursion capabilities based on a specific volume, so I guess as mentioned, the recommended sealed volume can be utilized for this part, but I would say try to stay UNDER that at the most. I believe that is what was said from the other member as well. Two of the best, "generalized" comments on 4th orders you can use thus far. That all considered, you should be very close to having a great response with those two design ideas considered within the same design.

Just remember, you will never be able to make the box too big as long as all aspects of the design are done right. You can however make it too small, so make sure to give enough room for it, or output will suffer greatly even if you never mechanically blow the sub(s). Mechanical limits may force some to exceed thermal ones without knowing it. This is why I would never design a BP without proper calculation, but if you want generalized input from me, I would go with what the other two member mentioned that I recited here. Hope that helps

this is why he is designing my box. lol

Moble Enclosurs
07-11-2012, 12:27 AM
this is why he is designing my box. lol

I just send you an email containing the design idea too, Falcons :D
Let me know what you think :D

Falcons
07-11-2012, 12:34 AM
I just send you an email containing the design idea too, Falcons :D
Let me know what you think :D

It's beautiful! And that response curve is exactly what I'm lookin for :D

double 07
07-11-2012, 09:17 AM
when are you going to build it MURPH?..........Sounds like I wasn't steering you wrong with my suggestions.........Let us know how it turns out....GOOD LUCK

Moble Enclosurs
07-11-2012, 10:32 AM
when are you going to build it MURPH?..........Sounds like I wasn't steering you wrong with my suggestions.........Let us know how it turns out....GOOD LUCK

Actually your suggestion for the sealed area was a very good one and one of the few that were correct. :D As long as the sealed area is kept below the recommended sealed volume chamber for this subs, it will work for a 4th, but the question is.....what is the recommended sealed volume? I don't refer to the manufacturers specs either.....I mean realtime calculated sealed volume.

SO, Yes, you were giving him good info :D

Kangaroux
07-11-2012, 12:08 PM
what was the tuning you had? I believe mine is going to be somewhere around 42-45ish... just waiting for it to be finished up..

40hz

kushy_dreams
07-11-2012, 07:02 PM
I'm in for the results of this build :cool:


I'm gonna be salty if it meters higher than what I was able to put up

wenn_du_weinst
07-11-2012, 07:07 PM
There are many box builders on here with knowledge.

eh be careful who you listen to.

murph
07-11-2012, 08:55 PM
I'm in for the results of this build :cool:


I'm gonna be salty if it meters higher than what I was able to put up

I doubt that it is only going to be one 12 on like 800 watts.

CAT MAN
07-11-2012, 08:56 PM
40hz
40? ........

Kangaroux
07-11-2012, 09:02 PM
40? ........

Yeah what about it?

kushy_dreams
07-11-2012, 09:12 PM
I doubt that it is only going to be one 12 on like 800 watts.

These are super efficient though, you will be surprised at how loud it will get on modest power.

murph
07-13-2012, 06:47 PM
Nvm we worked it out.

Moble Enclosurs
07-13-2012, 06:54 PM
Hey Murph! I got your message and I should be able to take one more because 2 of the recent ones were willing to wait til I get back lol. So, just let me know either way :D No worries!

rebelfromva
07-13-2012, 06:56 PM
holla @ ram murph

murph
07-13-2012, 07:02 PM
Hey Murph! I got your message and I should be able to take one more because 2 of the recent ones were willing to wait til I get back lol. So, just let me know either way :D No worries!

I emailed you back go ahead and do it.