MartinLogan Motion 4i Woofer Replacement

Written By: Austin Paul

Difficulty

Difficult

Steps

Time Required

1 - 2 hours

Introduction

Follow this guide to replace the woofer inside your MartinLogan Motion 4i model MO4IBL.

The woofer in a speaker generates low frequencies. A speaker with a failing woofer makes a fizzing sound.

You must have the back cover removed from the Speaker to start repairs. If you have already removed the back cover, please skip to step 7.

In step 9 you will need a soldering iron to take out 2 wires off the woofer.

Before beginning, the woofer is highly magnetic so keep your phone and other electronic devices away from it

Remove the speaker grill from the face of the speaker by using both hands to grip both ends of the speaker grill and pulling up to release the magnetic ends.

Remove the six caps from the outer edge of the face of the speaker with an iFixit opening tool.
Make sure to remove the rubber caps slowly and carefully so that the ends won't break off and create a blockage above the screws.

Remove the six 4 mm Phillips #2 screws that are located inside each of the holes where the rubber caps used to be.
The screws vary in depth, therefore you will need a Phillips #2 screwdriver that is around 6 inches in length from the tip to the start of the handle.

Place the device face-down, then lift off the back case with both hands.
The speaker sometimes takes a little effort to remove the speaker back, so we recommend that you give it a couple shakes by placing each hand on the speaker face and the back when shaking.
If you decide to use the shaking method, make sure you're near an immediate surface near you just in case it drops.