This is a fantastic subwoofer when placed and tuned correctly (I know as I used to own one). This unit I got from a friend. It needs a simple re-cone job (or maybe just glue). It works perfectly, but the surround is coming apart from the diaphragm which creates a loud rattling sound that is most noticeable between 50-90 Hz. It’s annoying, but fixable.
The driver motor operates perfectly according to my testing, and this thing can play LOUD (normally with very little distortion). Bass extension is better than average for its size and price, but not best in class, however the sound quality is (normally) magnificent.
The company near me that would fix this shut down, so I have no where to take it. I don’t want to screw it up, so I hope whoever buys it knows what they’re doing and can fix it properly, or knows someone who can.
As you’ll see from photos, despite not having the original packaging or other materials, this thing is well-packed, and it’s in otherwise excellent condition.
SPECS: Sunfire True Subwoofer MK-II
10" Drivers - Passive Radiator Design
Manufacturer's FR Specs: 18 Hz - 75 Hz ± 3 dB
Built-in Amplifier: 2,700 watts rms
Size: 11" H x 11" W x 11" D
Weight: 43 pounds
See also: https://hometheaterhifi.com/volume_4_4/sunfiresubmk2.html