Monolith by Monoprice M-IWSUB8 8" In-Wall Subwoofer P/N 42831 Open Box

Retail price (new): $599.99

Open-box Monolith by Monoprice M-IWSUB8 8" passive in-wall subwoofer, P/N 42831.

Shown in original foam with the installation guide / mounting template resting on top. Open-box warehouse unit — not installed. Photos include Monoprice stock images plus our open-box warehouse photo.

OVERVIEWAdds powerful bass to an in-wall / in-ceiling home theater without floor space. Passive design — requires a suitable subwoofer amplifier (not a typical AVR speaker-level output alone). High-excursion 8" polypropylene cone with rubber surround. Magnetic white paintable grille. Heavy-duty mounting tabs for standard 16" wood stud walls. Spring-loaded binding posts.

KEY SPECS (manufacturer / published)• Driver: 1× 8" polypropylene cone, rubber surround• Frequency response: 36 – 200 Hz (±3 dB)• Sensitivity: 91 dB• Impedance: 4 ohms• Crossover: acoustic filter, 120 Hz @ 12 dB/oct (can be disabled via jumper for use with external DSP/crossover)• Inputs: spring-loaded binding posts• Grille: removable magnetic, white, paintable• Dimensions (with grille): approx. 11.9" × 13.3"• Dimensions (without grille): approx. 10.8" × 12.2"• Fits standard 16" wood stud wall cavities

CONDITIONOpen box. Packaging opened for inspection and photos. Appears unused / uninstalled with install sheet and foam present. Sold open box.

Note: This is a single 8" M-IWSUB8 (42831), not the dual-driver M-IWSUB82.