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ShaunMac
03-27-2003, 07:23 PM
Just trying to understand some of the aspects of
porting a box.

Does the volume of the port dictate the tuning freq.
of an enclosure?

Does the size of the port opening have a lot to do with
the tuning freq? large slot vs small slot

If I have a 6"diameter 35" long port that yields 989.1cu in.
Would a slot port that has the same volume give you
the same tuning freq?

Example: 16" x 4" port that's 15.45" long

Randy Savage
03-27-2003, 07:46 PM
Originally posted by ShaunMac
Just trying to understand some of the aspects of
porting a box.

Does the volume of the port dictate the tuning freq.
of an enclosure?

Does the size of the port opening have a lot to do with
the tuning freq? large slot vs small slot

If I have a 6"diameter 35" long port that yields 989.1cu in.
Would a slot port that has the same volume give you
the same tuning freq?

Example: 16" x 4" port that's 15.45" long
The size of the port dictates the tuning frequency...example, take our 15" Hc...

4.223 cubes, tuned to 35 Hz...

The port is 14" High, 2" wide and 10.16" long

now, lets tune it to 40 hz....

port is now 14" high, 2" wide and 6.75" long.

crakerhead
03-29-2003, 12:23 AM
how do you determing the tuning freq?

evo2k3
03-29-2003, 03:25 PM
large slot vs small slot determines port velocity....the bigger the port area the slower the air moves and the less change you have of port noise......there are many different variency of port sizes, generally you want to use something like winisd to figure out your min. port area then calc the length based upon that. The frequency is determined by you...generally daily drivers tun between 28-36hz.....the lower of that range is GENERALLY used for larger drivers (12's and 15's) where the higher range may be used more for 10's.....again that generally, they are many who stray away from that, its all about preference.