All symbols starting with `d' in src/od-acorn

• DEFAULT_SOUND_BITS src/od-acorn/sound.h:34
• DEFAULT_SOUND_FREQ src/od-acorn/sound.h:35
• DEFAULT_SOUND_MAXB src/od-acorn/sound.h:33
• DEFAULT_SOUND_MINB src/od-acorn/sound.h:32