How to: Install the ACC 004 (A,B,C)

Here are a pair of ACC 004 A backplate/crossover assemblies ready to be used to upgrade a customers speakers:

The ACC 004 (terminal and backplate only) installation is similar to this process, except that you will either have put your crossover components of choice and wires on it yourself, or, after installing, you will connect it to a separate crossover board mounted nearby inside the cabinet.

This work is performed best on a large, well-lit level surface, with a soft covering to protect the speaker box. Pick something that you won't get in trouble for using if it gets dirty or stained by glue, etc.

I use bits of leftover carpet on my speaker building/repairing bench - this is almost an industry standard.

The first step is to carefully remove the speaker components and set them aside.

Then, remove the fiberglass stuffing in order to get at the inside of the back panel.

By hook or by crook, remove the old backplate and any glue, leaving the inside of the hole clean and ready to work with. I find a mallet and a chisel to be invaluable in this step.

Next, draw some nice straight and true lines to indicate the location of the hole. In this case, simply extending the edges of the hole with a straightedge works fine. For a round hole, a little more care is needed to keep these lines square with the edges of the cabinet. This only matters if you want your binding posts to appear level and centered in the hole when you are done.

Next, place the ACC 004 (A) over the hole, using the lines to align it neatly. Mark where the edges of the backplate lie, so you can easily put it back in place.

Take it away and apply some gasketing material around the hole. This picture was set up with some common caulk - it is a bit more demanding, but when I do this job I usually use hot glue. Perhaps the best overall is a silicone adhesive (a/k/a RTV, aquarium sealant, gasket maker, silicone window caulk, etc.), since it dries slowly (overnight), seals well, and uses a non-toxic solvent - vinegar, basically.

Place the board back over the gasketing material, press it firmly down, and screw it in with the supplied 1" #8 screws. Drilling pilot holes for these screws is optional, but will help a lot if you don't have a power screwdriver with a long extension bit.

Once the backplate is firmly attached, draw the wires through the speaker holes and replace the fiberglass damping material. I use a consistent color scheme on speaker wires, which I inherited from my days at Genesis. Black is always "-", and is set up so it is common to all drivers. Red is for the woofer "+", yellow for the tweeter "+", and if there is a midrange, its "+" wire will be marked with green.

Here you see how I wrapped the wires around each other to stop them from falling back into the box while I replaced the fiberglass.

Now carefully replace the driver gaskets, attach the wires to the drivers, and screw them back in place. Test the speaker at a low level to make sure everything went together properly. Are the highs coming from the tweeter? Lows from the woofer? Nothing rattling or leaking air? Turn up the volume a bit, paying attention to the same things. Once a decent listening level has been reached, you should let everything "break in" for a bit, even overnight, and then start enjoying your upgraded speakers!

This is what the ACC 004 looks like peeking out the back of the finished speaker: