View Full Version : which is more accurate? winisd or 12volt

11-08-2011, 10:08 PM
I was getting the port length for my box and looked at both sites when finding the port length for it. Winisd came back with 30.2 in and 12volt gave me 31.5. I know these aren't much off from one another but is one more accurate or should I even care?

11-08-2011, 10:13 PM
close enough, if you rally want to tune it as closely as possible start long by another inch and trim .5" at a time till you hone in on the frequency you are looking for, but for daily, meh, its good enough

11-08-2011, 10:26 PM
Well to answer my own question I used the formula to see what frequency (as found on the jl audio site here JL Audio - Car Audio Systems (http://mobile.jlaudio.com/support_pages.php?page_id=165) ) each length corresponded to. I was aiming for a 35.5 Hz frequency. Winisd gave me a length of 30.2 in for the port but using that in the equation gave me a frequency of 36.2497 Hz. Using the 12volt calculator gave me 31.5 in which gave a frequency of 35.599 Hz using the equation. So the12volt.com's port length calculator is more accurate than the winisd one. This may help someone else who is wondering the same thing.

11-11-2011, 01:49 PM
I don't know which calculator you were using at 12volt, but another thing to consider is that winisd also tries to calculate port velocity when giving recommendations. Sometimes it will recommend a slightly different frequency for a port if you have set the number and size of ports to a setup that will be higher than recommended port velocity.

You can test this by adjusting the surface area of your port or adding additional ports. It should then recommend the exact frequency.

Nut Hair Trick
11-11-2011, 02:00 PM
Search "Torres box tuning calculator" and download that. I use a combination of all 3 of Torres, winISD, and 12volt for different things.