Lanzar Kill-O-Hurts
Subwoofer System
www.lanzar.com
If you're looking for killer bass, Lanzar's latest heavy-duty ported subwoofer system may be your answer.
by Brian Smith
The KH15 is a 15-inch woofer that was delivered for testing in a tuned enclosure of about 3.5 cubic feet. Features include a hefty cast basket, treated paper cone with foam surround, and a nifty Kill-o-Hurts logo on an inverted dust cap.

Subjective
I nearly blew an o-ring getting this thing into the rear hatch of our test car. Although I've never been a fan of tuned enclosures, especially in cars, I must admit, this one sounded really good. If I hadn't had to run my arm up the tuning port to evacuate a few leftover packing peanuts, I'd have sworn that this was a sealed enclosure. The sub's transient response is sharp and tonal accuracy is excellent. In fact, the only thing that gives this system's bass reflex status away is a lack of output at the absolute bottom range of a pipe organ. Overall, this is a solid-sounding woofer that would be at home in almost any system.

Objective
Impedance measurements show a maximum of 49 ohms at 51 Hz and a minimum of 4.7 ohms at 23.5 Hz. Average impedance measured 10.2 Ohms. Out-of-car measurements presented a bit of a challenge. When measuring a woofer's response outside the confines of a car, it's necessary to get the mic quite close to the enclosure to avoid room interactions. With a tuned enclosure, this process involves finding the spot where the output of both the woofer cone and the port sum correctly. You know you've found the spot when the ultimate response rolls off at 24 dB-per-octave (fourth order) below the enclosures tuning frequency. The impedance curve for this system shows a tuning frequency of about 23 Hz, but we were unable to find a mic position that provided the proper roll-off below this frequency. In a last ditch effort, we hauled this monster outside and tried a free-field measurement. The resulting response still didn't look anything like an enclosure tuned to 23 Hz. Our best guess is that the long port in this box is a bit restrictive, causing the system to behave more like a sealed box than a tuned one. This could explain its better-than-expected performance in our subjective evaluation.

In-car measurements show a one watt in-car sensitivity that averages 101.3 dB from 20 Hz to 50 Hz. In-car response is very smooth with a slight low-frequency rise and only 2.5 dB of power compression at 300 watts (top trace).
PRICE & CONTACT: Call for pricing; TEL: 718-236-8000; www.lanzar.com