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View Full Version : What does transfer magnitude function in WinISD tell me?



coolest user
01-27-2008, 06:34 AM
I enter two different subs in two different size boxes and got two different graphs.

The only driver data I entered was Fs, Vas, Qts, xmax, and driver displacement. Is more driver info needed for an accurate graph?

Anyway, here are the two graphs. Any info on what either is telling me would be great... one box is 5.25 cu ft with three 12's and the other is 4.00 cu ft with three 10's.





http://i150.photobucket.com/albums/s91/supercharged232/12s.jpg



http://i150.photobucket.com/albums/s91/supercharged232/10s.jpg

helotaxi
01-27-2008, 11:20 PM
Transfer function magnitude shows you the response of the bottom end of the freq range of the enclosure compared to reference. It will allow you to determine the rolloff freq and the width and amplitutde of any response peaks and is useful for comparing different alignments. It does not indicate how the setup will respond in car, it does not indicate relative SPLs and it doesn't change with power applied.

coolest user
01-27-2008, 11:24 PM
Thanks.

Ok, so it's not an indication of a loud, peaky, or boomy box?

Does the line in my second graph just mean the sub will lose sound fast as the frequency goes down?

helotaxi
01-28-2008, 12:10 AM
I can't see the pics. It will show you a peak. That't the point of that graph. Peaky and boomy are usually a bit the same. A big peak is going to sound bad.