"Pure Orange" is generally:
- red: 100%
- green: 50%
- blue: 0%
So a linear equivalent in hex to that extremely dark red would be: #0F0800
However, perceptual colour rules are rarely so simple. The correct way for any colour would be to do a mathematical transformation to HSV, make the hue shift from 0° (red) to 30° (orange), and transform it back. Surprise, you get the same value.
If you're talking audio, I've no idea.
For written work, I've always liked Ursula Le Guin's prosaic adaptation. Jane English's translation is a great one too, but less prose.