Leethomas
Member
Earlier this year I bought a pair of Sequel 2's that had a problem with parts of the panels, in that certain sections had little or no output. As I purchased these pretty cheaply, I thought it was a good opportunity to 'have a go myself' at refurbishing/repairing these speakers; I am an electronics engineer by profession and am not put off by doing stuff myself.
The advice of some people from this forum was to get new panels, but I wanted to have a go at least-nothing to lose!
Well, now I have successfully renovated these panels, by disassembling them, removing the old conductive coating, and then recoating them with a new conductive coating, and reassembling them.
The results are pretty marked; much higher output (probably 6db or so), and a large increase in the midrange content making them sound much 'fuller' and balanced, or brighter. In fact, they sound damn good!
If anyone's interested, I can tell you that it is not an impossible task, and encourage you to have a go!
Here's how I did it:
After removing the panels and disconnecting the stator and diaphragm wires from the crossover board, the first task was to seperate the front stator from the back one; This was a slow task, the stators are attached at the TOP and BOTTOM, not the sides. So I used a craft knife to cut away the rubbery material that holds them together; it should be cut as near as possible to the TOP stator.
This can take several hours, not to be rushed. See photo 1.
After this, the top stator was be carefully removed from the bottom, with (hopefully) the mylar film intact! See photo 2.
After so many years, the mylar film was very dirty! The next stage was to remove the dirt and the conductive coating; This was relatively easy and I used methylated spirit with cotton wool! You won't believe the amount of dirt on the film!
See photo 3. Note the dirt!!
The conductive coating does come off, because I tried connecting them up after this process and-no sound!
Well it goes without saying that some new conductive coating will have to be applied to the film. After some research I used a fluid supplied by ER audio of Australia. I cannot praise Rob Mackinlay highly enough as he was incredibly helpful with tips and advice on how to go about this project- a real star, and I suspect he has some pretty good kits too! The fluid was inexpensive, and is water based and applied with a sponge supplied.
Note there is a copper strip which runs up one side of the film. This is connected to a wire that goes to the crossover board. this strip has to contact the new coating as and so the coating needs to be applied over this strip. In fact I attached another strip supplied by Rob to get better conductivity on each side of the film. See photo 4.
Photo 5 shows the application of the fluid.
See part 2 for the rest of this project.
The advice of some people from this forum was to get new panels, but I wanted to have a go at least-nothing to lose!
Well, now I have successfully renovated these panels, by disassembling them, removing the old conductive coating, and then recoating them with a new conductive coating, and reassembling them.
The results are pretty marked; much higher output (probably 6db or so), and a large increase in the midrange content making them sound much 'fuller' and balanced, or brighter. In fact, they sound damn good!
If anyone's interested, I can tell you that it is not an impossible task, and encourage you to have a go!
Here's how I did it:
After removing the panels and disconnecting the stator and diaphragm wires from the crossover board, the first task was to seperate the front stator from the back one; This was a slow task, the stators are attached at the TOP and BOTTOM, not the sides. So I used a craft knife to cut away the rubbery material that holds them together; it should be cut as near as possible to the TOP stator.
This can take several hours, not to be rushed. See photo 1.
After this, the top stator was be carefully removed from the bottom, with (hopefully) the mylar film intact! See photo 2.
After so many years, the mylar film was very dirty! The next stage was to remove the dirt and the conductive coating; This was relatively easy and I used methylated spirit with cotton wool! You won't believe the amount of dirt on the film!
See photo 3. Note the dirt!!
The conductive coating does come off, because I tried connecting them up after this process and-no sound!
Well it goes without saying that some new conductive coating will have to be applied to the film. After some research I used a fluid supplied by ER audio of Australia. I cannot praise Rob Mackinlay highly enough as he was incredibly helpful with tips and advice on how to go about this project- a real star, and I suspect he has some pretty good kits too! The fluid was inexpensive, and is water based and applied with a sponge supplied.
Note there is a copper strip which runs up one side of the film. This is connected to a wire that goes to the crossover board. this strip has to contact the new coating as and so the coating needs to be applied over this strip. In fact I attached another strip supplied by Rob to get better conductivity on each side of the film. See photo 4.
Photo 5 shows the application of the fluid.
See part 2 for the rest of this project.
