M&K IW500 Backbox In-Wall Speaker: Install Guide

The M&K Sound IW500 is a backboxed in-wall loudspeaker and the first "2-in-1" THX Certified Dominus in-wall model — it meets identical performance specs vertically or horizontally. THX Certified Dominus is THX's largest performance class, bridging large home-cinema speakers and commercial cinema speakers, suited to rooms up to 184m³ (6,500 cu ft) and viewing distances up to 6m (20ft). This guide covers placement, LCR/stereo orientation, cutout and dog-screw mounting, wiring, and specs.

What's supplied

• Cut-out template integrated into the packaging for marking wall position and cutout dimensions

• Damping pads, cable fittings, and push-terminal connectors for quick install

• Dog-screw mounting system with self-locking clamps for solid wall attachment

Placement

Set the height from the acoustic "on-axis point" — the sightline through the centre tweeter sitting between the soft-dome midranges. For both stereo (2-channel) and home cinema (LCR 3-channel), put the on-axis point at roughly ear level at the main listening seat.

LCR orientation (home cinema)

M&K recommends fitting the IW500 vertically for LCR, tweeter at ear level across the front soundstage — this gives 100% consistent coverage and identical horizontal dispersion across all three screen speakers. If you're not using a projector with an acoustically transparent screen, the IW500 is also certified horizontally as a centre channel, which suits large flat panels. Imaging stays pinpoint either way.

• Acoustically transparent screen: place on a centre line with each tweeter as close to ear level as possible (Fig. A).

• Non-transparent screen / flat panel: the centre can go horizontally above or below the screen; nudge the left and right up or down toward the centre's horizontal position. Keep all three LCR speakers as close to the same horizontal plane as possible for soundstage cohesion (Fig. B).

Stereo orientation

Follow the same rules for two-speaker stereo. Set the left and right equidistant from the centre line of the main listening position.

Installation

The IW500 fits masonry, plaster, or a purpose-built baffle wall (typically a 2x4 timber frame with a flat MDF/timber floor-to-ceiling baffle behind an acoustically transparent screen, often with rockwool or similar acoustic treatment). In every case the steel front fascia mounts flush with the wall surface.

Tools required: T25 Torx drivers and bits, a cutting tool, and a wire stripper.

Use the 2-piece carton template (it matches the speaker's outer dimensions and has a push-out cutting section):

1. Use the overall carton template to visualise the system position on the wall before pushing out the cutting template at the perforated lines.

2. Hold the pushed-out cutting template against the wall and mark the cut line. Don't cut directly on the template.

3. Cut to the inside of your marked line.

4. Connect the in-wall cables to the speaker, then seat the cabinet into the wall cut.

5. With the cabinet in place, turn the front Torx screws clockwise to activate the dogs. Tip: first turn each screw ¼ turn anti-clockwise to disengage the dog from its rest position, then clockwise to tighten.

6. Check the IW500 is perfectly aligned.

7. Fit and align the optional magnetic grille — install complete.

> Practical notes: If power-driving the dog screws, set the tool's torque/tension to avoid over-tightening, and use low-to-moderate speed. To remove the speaker for service, slowly loosen the front dog screws until you feel slight resistance, turn the dogs back to neutral, then pull the cabinet from the wall cut.

Connection

Use the solid push terminals — they take cable up to 5mm / AWG 6. Wire every speaker in correct phase: positive (+) amplifier lead to the red (+) input terminal, negative (-) to the black (-). Marked +/- speaker cable makes the visual phase check easy at both ends.

> Note: All M&K speakers are designed to run with M&K subwoofers. The THX Certified Dominus IW500 pairs ideally with the THX Certified Dominus X15+ powered subwoofer in large cinema rooms.

Specifications

This article was adapted from M&K Sound's original guidance — Source PDF Habitech-edited for UK trade installer context. Original © M&K Sound.