External Party Speakers

Call me crazy, but I’ve been looking without success for a suitable method to connect external speakers without having to trail wires out the door. One problem is that modern amplifiers “float” the speakers, which means none of the leads can be tied together or grounded (in the “old days”, it only took five wires to run a set of front and rear speakers, now it takes 8).

My solution was to build a box to mount a 4-lead clip connector, accessible from outside. I had to do all the metal bending with a block of wood and hammer, all the cutting pretty much with a bandsaw. I prepared a set of shims from .062 sheet to provide room for an interior gasket. The hinge came from a piece of piano hinge left over from another project. The lid is reinforced with a thin sheet, cut out and bent with flanges and attached with 3/32″ flush rivets. These rivets can be “bucked” with a small hammer–no need for a squeezing tool here.

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The rought corners were trimmed with a stationary belt sander.

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I had originally intended that the cover fit precisely in the shell opening, but realized that that would have required a level of cutting precision I’m not equipped to deliver, so I overlapped the cover about 3/16″ on three sides. The cover is offset from the hinge with two .036 spacers, allowing the hinge to be inside and the cover to rest flat on the outside. This also allows the fully assembled box to be installed from the inside of the shell.

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Although it seems counter-intuitive to have the door fold down, the ribs on the inside of the door would be a hazard while connecting the wires. I’m hoping the gasket, yet to be installed, will prevent any leaks.

To finish, I need to buck four rivets and connect the wiring. Since all the leads to the speakers are floating (electrically speaking, of course), I only need to wire in a double pole, double throw switch to fully switch between the rear speakers in the bedroom to the external connector.

Getting even closer to being ready for Burning Man! However, I am pre-calculus these days, so I know you can never be ready–you get halfway prepared, than another halfway, then….