the cab or part of the shell [8]). Of course, the cab needs to be
fully glassed and sealed for the enclosure to be effective.
Figure 8 shows one such installation in an Atlas Alco RS-1. Here
the shell was most of the enclosure. The speaker is caulked into
the shell and has a bit of styrene, not visible in [8], between
the top of the shell and the front of the speaker to complete
the enclosure. The speaker wires (purple) and rear LED (black)
pass through notches in the styrene wall and are caulked in
place. Glue the speaker and the styrene with caulk. That way,
they can be removed if necessary, unlike what happens with
styrene cement.
I don’t recommend this design without a LED light. My luck
would be that an incandescent bulb would burn out as soon as
7. Kato SD45 with a 16 x 35 mm speaker and baffle over
the truck.
7
I had the loco back together and I’d have to take the loco apart
and rip the speaker out to replace it.
One thing to be very careful about. Make sure that the rear
truck can twist and turn and articulate up and down. If the
speaker constrains the motion of the truck, two things will
happen. The truck will dampen the sound and the loco will be
prone to derailing. I’d explain how I know this, but that would
be an entire column by itself.
One switcher that I did with the speaker mounted in the bot-
tom of the cab had terrible sound when I tested it. A bit of
judicious pressure on the cab showed that there were lots of
openings in the cab that would let the sound escape. It took a
bunch of caulking and gluing to make the sound work. Whew.
8. Atlas Alco RS-1 with a 16 x 35 mm speaker mounted in
the cab and short hood.
8
DCC Impulses Column - 8
MRH-Jul 2014
