JL Audio Fathom F113 (Version 1)

Bought new in 2007 and well-cared for.  Loved it and makes any set of speakers (stereo or multi-channel) sound that much better. Original box, calibration microphone, and owner manual.  All the technical mumbo-jumbo follows:
Powered, sealed-box subwoofer. Drive-unit: 13.5" W7 cone with 3.5"-diameter voice-coil and 4" peak–peak excursion. Magnet weight: not specified. Low-pass filter: variable, 30–130Hz; 12dB or 24dB/octave. High-pass filter: not supplied. Inputs: stereo or mono balanced Neutrix (single XLR connector), stereo or mono unbalanced (single RCA connector). Input modes: Master, Slave. Outputs: single balanced Neutrix (XLR) to additional subwoofer. Input sensitivity: not specified. Input impedance: not specified. Controls: Power (On, Off, Automatic Signal Sensing), Automatic Room Optimization (Demo, Defeat, Calibrate), Level (Reference, Variable), Master Level (variable, full mute to +15dB over reference), Lights (On, Off, Dim); Low Pass filter (–12dB, –24dB, Off), Low Pass Frequency, Extreme Low Frequency (ELF) Trim (variable, –12dB to +3dB at 25Hz), Polarity (0°/180°), Phase (variable, 0–280°, at 80Hz). Amplifier: class-D, 2500W RMS short-term. Frequency response: –3dB at 20Hz, –6dB at 130Hz. Distortion: not specified. Automatic Room Optimization (ARO), defeatable; calibration microphone included. Maximum peak SPL output at 50Hz: 120dB at <10% THD at 1m, input 0.25V input, level control set to maximum.
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