Frank Carter
Screenwriter
- Joined
- Mar 12, 2002
- Messages
- 1,187
Just finished my TP tubes and I have 9 20oz bags of polyfill to play with. Instead of just stuffing a bunch in, I want to know if this would be the correct way to measure how much my effective volume is with the polyfill.
1.) By using WINISD I know at the tuning frequency a woofer's excursion is at it's lowest. With my SPL meter near the woofer's cone I'll measure the the freq where output is the lowest to find the tuning frequency of the enclosure with no polyfill.
2.) If I now add one bag of polyfill, and I remeasure the tuning frequency and it's lower this means the polyfill did it's job.
3.) By using this new lower tuning frequency and my known port size/length, I can work backwards and find what internal volume would be needed to get the new tuning frequency using my ports.
4.) Repeat steps 2 & 3 until I get my desired effect or it doesn't lower the tuning frequency any more.
I just wanted to know whether this would work before I take the time to do this. Does anyone else do this(or some other method) when they add polyfill? I plan on sharing my results so if anyone's interested they can read.
Thanks
Frank
1.) By using WINISD I know at the tuning frequency a woofer's excursion is at it's lowest. With my SPL meter near the woofer's cone I'll measure the the freq where output is the lowest to find the tuning frequency of the enclosure with no polyfill.
2.) If I now add one bag of polyfill, and I remeasure the tuning frequency and it's lower this means the polyfill did it's job.
3.) By using this new lower tuning frequency and my known port size/length, I can work backwards and find what internal volume would be needed to get the new tuning frequency using my ports.
4.) Repeat steps 2 & 3 until I get my desired effect or it doesn't lower the tuning frequency any more.
I just wanted to know whether this would work before I take the time to do this. Does anyone else do this(or some other method) when they add polyfill? I plan on sharing my results so if anyone's interested they can read.
Thanks
Frank