How to calculate T/S parameters for a Pro Tech subwoofer

[Navy Chief]

I have a pair of Pro Tech CH12D4 subs. There are no longer any published specs that I can find. PJ's gave all the data away when they sold the Pro Tech brand almost a decade ago. I want to build a band pass box for these subs but need T/S specs to calculate it. I know I can buy a speaker calculator from Dayton Audio, but is there another "cheaper" way to do it. I have a multimeter, but that is about it. Any help would be great.

[squeak9798]

The subwoofer DIY Page - Measurements
Measuring Loudspeaker Driver Parameters

Or google "how to measure thiele small parameters" and search any of the various links.

Additionally, Vance Dickason has an entire chapter dedicated to measuring the TSP in his Loudspeaker Design Cookbook.

Short story is that it's possible to do it without a woofertester, but you'll need more than just a DMM, as you can see from the above links.

Honestly it's probably worth it to just purchase a woofertester, and if you never plan to use it again resell it at a small loss on the forums.

[Navy Chief]

Originally Posted by squeak9798

The subwoofer DIY Page - Measurements
Measuring Loudspeaker Driver Parameters

Or google "how to measure thiele small parameters" and search any of the various links.

Additionally, Vance Dickason has an entire chapter dedicated to measuring the TSP in his Loudspeaker Design Cookbook.

Short story is that it's possible to do it without a woofertester, but you'll need more than just a DMM, as you can see from the above links.

Honestly it's probably worth it to just purchase a woofertester, and if you never plan to use it again resell it at a small loss on the forums.

I was considering the buy and resell idea, just looking for other options. Anyone here rent their woofer tester, lol