SoundTraxx DSX decoder installed with TCS A6X motor/lighting decoder. The A6X provides 1.5 volts via a voltage regulator to the lamps; the speaker is a GC 16x35mm 8 ohm .5 watt model mounted in an American Hobby Distributors small oval enclosure. Note the black cardstock covering the rear open louvres in the rear of the shell. This is to improve shell baffling. The interior pack was removed to make room for the DSX decoder. The hold-up capacitor (220uFD) is mounted on the frame next to the DSX decoder.