B&W 801 Matrix Fried Crossovers??

[Tripspike]

We wouldn’t have the smoke clue for those.

All the drivers should come out and get tested.

dave

So I tested the driver on the LF and it measures 6.1 ohms.

 

[Mooly]

What about the others?

If you use the 'diode check' range on a DVM you might possibly hear each driver 'click' as you connect/disconnect the leads.

(And remember you might have to isolate one lead of the driver to avoid reading across coils and resistors in the crossover)

 

[markbakk]

The protection circuits were not included in the Mark 3, which will explain the gaps in the board.

Their removal was apparently to do with the Mark 3 having a more robust tweeter than the Mark 2.

The manual states otherwise. Which of course doesn't imply you would be wrong though.

So I tested the driver on the LF and it measures 6.1 ohms.

Mechanical damage could have been done, the voice coil former hitting the back pole piece being an often occurring issue. Or coil windings may have come loose from heat.

Anyway, the dark grey and blue wires next to the blue coil are the midrange leads, the red and grey next to the large yellow cap should connect to the tweeter. The other red and grey lead next to the red coil are the input leads. Solder them loose and connect the 1,5V battery intermittent, you should hear the clicking from the drive units.

 

[Tripspike]

I had my electronics buddy look at the board and he found a burnt resistor. It is a Bennic 7W 2R2J. How do I find a compatible resistor replacement as these are not readily available from my search results? Thanks for any input.

 

[AllenB]

You should be able to find a 2.2 ohm resistor. I'd consider 10W, and having it stand off the board to allow air flow.