Click an image above to enlarge.

Go to page three
Go back to page one

Panel & bias power supply replacement process

MartinLogan will also ask you to update the ARC Genesis firmware within your speakers as a matter of course. A short firmware guide is also supplied. I did question validity of the firmware update as I do not see the connection with the ARC software and panel issues, however, MartinLogan advised this should be completed as part of the ‘overall process.’
The numbers, 1 – 4, 5 - 9 etc should assist when working with the MartinLogan guide.

Preparation (click the photographs above to enlarge)

For my own piece of mind I first cut two separate pieces of wood to the exact height (or tilt) of my speakers. This will make the height set-up of my speakers much easier when I am ready to place them back into position. The pieces of wood will also serve as supports while I adjust the spikes and help to protect my porcelain tiled floor. I then marked the exact position of the floor spike protectors (just in case they moved out of position during this process). Again, this will make speaker repositioning easier.

1 – 4 Prepare a soft surface and lay the speaker on one side. Unscrew floor spikes and glider feet with ½” allen key. Set both floor spikes and glider feet aside. Lower the base panel gradually onto a support plinth (you will not be able to lower the base to the floor until you complete the next harness removal step). Disconnect the two amplifier harnesses from the circuit boards (two cables left).

Once the two amplifier harnesses are removed you can then remove the ESL panel harness (black sleeved cable on the right) from its bias power supply.

At this point I would recommend swapping out the old bias power supply circuit board for the new one (if suppled). The old power supply circuit board is removed by simply removing the four corner screws.

Disconnecting the two amplifier harnesses (red and black cables to the left) & ESL harness (black sleeved cable to the right).

Swapping out the old bias power supply circuit board for the new one.

5 - 9 If you have not already done so, remove the front grill, then remove the left & right grill insulators. You may need to use a clean flat head screwdriver to gently prize the insulators at the top, or bottom. Once you get part of the insulator removed it will then pull away easily. It is important to remember the correct angle the insulators come out, so you can squeeze them gently back into place when you refitting later.

Using a 5/32” (or 4mm) hex driver, remove the screws along the front (each side) of the grill core. Once removed, you will see the airframe mounting brackets.

Removing the screws from the grill core.

10 – 14 Using a 3mm hex driver, remove the two screws (one each side) connecting the air frames to the speaker base.

Using a 5/32” hex driver, remove the airframe mounting screws (left & right). Make a note of the white wire clip location. You should now be able to remove the air frame from the speaker font.

Using a 5/64” (or 2mm hex driver) carefully remove the four small screws holding the midstrut cover to the midstrut. Note – it is easy to damage these small screws if they do not unscrew after a few short sharp turns of the hex driver. If you have problems loosening these screws, you could try using WD40. If this does not work, you may have to drill the screw head off using a carbide drill bit (as I did). However, please seek further advice from your distributor if you experience problems first and foremost! You will have to source replacement of any screws removed in this way as MartinLogan will not supply them!

Make a note of the white wire clip location.

Drilling off the head of one of the screws holding the midstrut cover to the midstrut.

Go back to Hi-Fi Experience Home Page

[ Top ]