Less than 10 Hours was used for a sample for JF-12
 
The versatile 12SW-4HE 12” high excursion subwoofer from GRS is designed to produce excellent low frequency extension in a variety of designs. Suitable for both sealed and vented enclosures, this driver the ideal replacement or upgrade for your existing subwoofers with worn out or blown drivers. Featuring extensive venting, rubber surround, high temperature voice coil, low Fs, and 12.5 mm of excursion the 12SW-4HE is built for remarkable bass response on a budget.
Key Features
High excursion and low Fs to produce powerful low frequency output
4-layer 2” voice coil on a thick aluminum former to handle up to 250 watts RMS
Venting under the spider, through the pole piece, and in the magnetic gap for excellent heat dissipation
Durable reinforced paper cone with rubber surround produces reliable and consistent performance
Extended frame and bumped back plate allow ample clearance for high excursion
GRS 12SW-4HE 12" Paper Cone Rubber Surround High Excursion Subwoofer 4 Ohm
 
GRS 12SW-4HE 12" High Excursion Subwoofer
Engineered for extended low frequency response and flexibility
The GRS 12SW-4HE 12” high excursion subwoofer from GRS is an ideal replacement driver for existing subwoofer systems or an excellent choice for new economical designs. Capable of producing powerful bass response in both sealed and vented designs, the 12SW-4HE is suitable as a drop-in replacement for most existing 12” subwoofers.
Key Specs:
 
Nominal Diameter: 12"
Power Handling (RMS): 250W
Power Handling (MAX): 500W
Impedance: 4 Ω
Frequency Response: 20-500Hz
Sensitivity: 84dB 2.83V/1m
Voice Coil Diameter: 2"
Maximum Linear Excursion: 11.7mm
Frequency Response & Impedance Curve
the GRS 12SW-4HE has a bass-centric response from 26Hz up to 500Hz and is highly efficient within its passband. This efficiency and a low QTS lends itself well to both vented and sealed subwoofers for incredibly deep bass from a 12-inch driver.
Bass-worthy construction
Extensive venting through the frame, pole piece, and magnetic gap dissipates excess heat to keep power compression to a minimum, even when driven hard for long periods. The rigid paper cone is supported by a large diameter spider and rubber surround to keep excursion linear while providing reliable performance. With a high temperature 2” voice coil wound on a thick aluminum former the 12SW-4HE can comfortably handle up to 250 watts RMS of power.