design question??

[civicbuild86 13]

i was looking up designs for front facing subwoofers/front facing ports.there was 2 designs that got me thinking......i see more people use the L-bend port on a suwoofer box .....like this

 

and less people use a design like this

 

 

im not a big box builder.....so can somebody tell me why most people use the L-bend instead of the dual chamber middle port design........is it because u get both subs working together in same chamber? and how would it change the air flow from side port to middle?

 

 

[Quentin Jarrell 671]

only difference is there will be less of a chance of premature unloading on the second one.  Besides that they are just two different ways that accomplishes the same thing.

[civicbuild86 13]

only difference is there will be less of a chance of premature unloading on the second one.  Besides that they are just two different ways that accomplishes the same thing.

i figured that too....with the premature unloading or subs unloading at different times with the first design inless u use one amp or slave one/strap if using two amps.....but would have thought the same enclosure would offer more vent velocity or pressure with 2 subs in one compartment than the other design.....figured the second design would be better for 2 amps that are seperate.....but idk

[Quentin Jarrell 671]

no both assumptions are incorrect.  amplifier has nothing to do with either

[civicbuild86 13]

no both assumptions are incorrect.  amplifier has nothing to do with either

if amp has nothing to do with it can u explain further what u ment by premature unloading then?

[altoncustomtech 773]

Unloading in an enclosure happens when the sub plays below tuning. However, what can happen in some cases is that one sub will unload prematurely, or before the other sub. Typically it is due to the orientation and placement of the port to the subs. What is typically found is that the sub nearest the internal port opening can prematurely unload. It all depends on the size of the enclosure and the port itself, how close they are, etc. and is therefore very difficult to account for or model from what I understand. Because it varies with every enclosure design it can sometimes not happen at all, not be detectable under normal listening levels, or can be so severe as to shred the sub long before reaching maximum output in the worst cases.

[civicbuild86 13]

Unloading in an enclosure happens when the sub plays below tuning. However, what can happen in some cases is that one sub will unload prematurely, or before the other sub. Typically it is due to the orientation and placement of the port to the subs. What is typically found is that the sub nearest the internal port opening can prematurely unload. It all depends on the size of the enclosure and the port itself, how close they are, etc. and is therefore very difficult to account for or model from what I understand. Because it varies with every enclosure design it can sometimes not happen at all, not be detectable under normal listening levels, or can be so severe as to shred the sub long before reaching maximum output in the worst cases.

didnt know that...thanks for all the help with my questions alton and quentin

 

 

but still dont know why i see most people with the first design .....maybe they dont know

Edited September 29, 2013 by civicbuild86

[Impious 1,476]

More difficult to design/build design picture 2 with the long port length of picture 1. Picture 2 looks nice and easy because of how short the port is relative to the enclosure depth. Look at how long the port is on picture 1. Much easier to accomplish with a single L shaped port.

[civicbuild86 13]

More difficult to design/build design picture 2 with the long port length of picture 1. Picture 2 looks nice and easy because of how short the port is relative to the enclosure depth. Look at how long the port is on picture 1. Much easier to accomplish with a single L shaped port.

yea it would be easier to build and design the L shaped port.....just figured there was a more complex reason lol