View Full Version : what am I looking at in Win ISD?

09-08-2006, 12:18 AM
Im still learning how to use this..
I know that the white and green line represents the two box designs on screen.
But not sure what the red and purple line is for...
Can someone shed a little light on this part for me?


09-08-2006, 12:23 AM
the red line is the 0db rolloff line and the purple is the -3db rolloff line


09-08-2006, 12:26 AM
is anything past the red line bad?
is anything past the purple line bad?

09-08-2006, 01:29 AM
Doesnt matter...its horribly innacurate...

09-08-2006, 01:46 AM
Doesnt matter...its horribly innacurate...
Then what am I doing wrong? keep in mind that Im a noob at this ported box stuff.

09-08-2006, 02:30 PM
the only thing wisd is good for is finding port length....even then it's off by some.

09-08-2006, 07:10 PM
winISD is not as inacurate as these guys are making it seem. winISD gives you an approximation of what that particular sub will output in that particular enclosure out in plane space not in a room not in a car. the two curves you have showing are impliying that the gray curve will play about 3.5db louder between 50~60Hz, that your cut off will be some where at 34Hz~40Hz and your F3 close to 30Hz. now there are other screens you have to pay attention to. that is the rear port air velocity wich i like to keep unde 16.5 m/s rms, and the cone excirtions wich should be keeped under double the xmax of the sub.

there is allot of good info on the help/ getting started and the content of the help files. that will realy help you use the software with more accuracy.

depending on the vehicle there could be any where from 3db to 12db or more in gain on the lower octaves. so take that into account when looking at the transfer function magnitude graph.

you can also visit link (http://linearteam.proboards12.com/index.cgi?board=winisd)
to further broaden your knowledge on winISD. altho a slow site, it is still full of very good info.