hey guys

just got bassboxpro and love it BUT theres something fishy goin on with the vent lenght calculations. my box wich is 2 cuft tune to 40Hz has a vent of 2X14.5X19.75, but acording to BBP it asks for a 22.75" long vent. WTF, did i do something wrong. or am i to asume the one is inacurate

 

When you did your box design with Bass Box Pro, did you choose to use fill, or no fill in the box(polyfill)? That usually affects the port length.....

[ August 21, 2005, 12:38 AM: Message edited by: Two Eights aka Jeep ]

 

NO FILL
i got a replay of Sounddomain

What is “end correction?” It’s an internal parameter that compensates for the fact that a vent usually appears to be slightly longer than it really is. This is because the air immediately outside each end of the vent will vibrate along with the air inside the vent. This is illustrated below:

The end correction of a round vent is equal to the internal diameter (Dv) of the vent. For example, a vent with an inside diameter of 2 inches will appear to be 2 inches longer than its actual length (Lv).

The end correction is affected by both the cross-section shape and the end type. BassBox Pro automatically estimates the end correction and uses it for its internal calculations.

Copyright 1992-2004 by Harris Technologies, Inc.

 

whatever bassbox pro says.... go with. I've yet to be wrong with that program. Is worked everytime. and the end result was ALWAYS exactly how the programs said it would be. BOXMOD is the best for the buck though. However.. if your nuts.. go with LSPCAD PRO or CALSOD.. they are $1k-$3k programs.. and are off the hook in every concievable way.

 

different port areas?

 

you also may want to do the update on the internet that can update the software. i have seen that before. but the program old or knew is preaty darn acurate! u can usually get the tuning freaquency within like 3hz with that program.

 

^^that sounds pretty close