Beautiful veneer - and shows the difference in woofer - not so beautiful - I am confident it will be soon looking as good as new!

Hi Peter,

Thank you very much, yes the veneers are stunning.

However one of the speakers is dead, no sound and I need to get inside to find out why.

Tried from the front, but that didn't work, so I tried removing the back, and was unsuccessful.

I read the manual but it offered little guidance. 

These speakers are like 99% flawless and I do not want to damage them with guesswork.

So how do I gain access to look for the main problem as well as remove the woofer and mid-range for re-foaming?

Jeff

Unscrew the back panel screws, unscrew the front woofer screws. Remove the woofer. Use your hand to poke through the woofer hole and push the back panel of. The back panel is tight to push of. Remove some of the sound deadening wadding for improved internal vision as to where to push. 

Be carefull as the crossover electrics are on that back board. May have to desolder a few things as the back panel comes of, but work slowly and you will see. 

Typo

May have to desolder some stuff WHEN the back panel comes of so as to remove the panel completly. 

Thank you Martin.

Oddly enough, this is what I already did, BUT I was afraid to push hard enough on the back panel. Even tried a rubber hammer.

I need to remove the woofers and mid-ranges for re-foaming anyway, but now I know how to get in an investigate.

Now I gotta hope that the fault is obvious enough for a layperson to recognize.

Could it possibly have anything to do with the over-ride protection? Had that issue with my MC120.2 speakers and had to bypass the protection circuit as switch are not available. (You might remember all that....)

Jeff

Thanks Cooker and Martin,

Opened up the M75 and this is what I found.

I checked the outlet for corrosion but the outlet was pristine. No broken wires, and the caps all look good. I swapped speaker cables just in case, but not the cable.

There is NO sound of any kind, so is there anything else to do other than send the board off for proper testing?

Jeff

Photo number 2

And photo number 3.

The last photo maybe the most important. Maybe.

All looks nice and original.