Theil and Small Parameters for the University C15W woofer (silver frame)

I recently had access to a Datyon Woofer Tester 3 to test the T/S parameters of this excellent vintage woofer. When I can, I'm also going to post comparative measurements using my ARTA jig. Of note, .. I consider the dual voice coil C15W to be a highly excellent woofer for my Karlson K-15 enclosure. Despite what literature would have one believe, I've sen Karlsons to be picky about what drivers they like (they prefer low mass cones, low Qts drivers). This driver+cabinet enclosure didn't just make the walls shake. It literally moved the whole first floor of place up and down. I don't think it made much bass below 50 Hz, but this is a real 50 Hz, not 50 Hz produced by some "subwoofer" you buy in the big-box store.

What does a Karlson look like? Here's a picture (not mine)


Series Voice Coils

* Piston Diameter = 330.2 mm
* f(s)= 69.98 Hz
* R(e)= 6.63 Ohms
* Z(max)= 74.00 Ohms
* Q(ms)= 3.708
* Q(es)= 0.365
* Q(ts)= 0.332
* V(as)= 91.420 liters (3.228 cubic feet)
* L(e)= 1.41 mH
* n(0)= 8.19 %
* SPL= 101.20 1W/1m
* M(ms)= 58.27 grams
* C(ms)= 0.09 mm/N
* BL= 21.58

Parallel Voice Coils

* Piston Diameter = 330.2 mm
* f(s)= 69.98 Hz
* R(e)= 2.32 Ohms
* Z(max)= 18.89 Ohms
* Q(ms)= 3.965
* Q(es)= 0.554
* Q(ts)= 0.486
* V(as)= 91.420 liters (3.228 cubic feet)
* L(e)= 0.36 mH
* n(0)= 5.39 %
* SPL= 99.42 1W/1m
* M(ms)= 58.27 grams
* C(ms)= 0.09 mm/N
* BL= 10.35