Chao Tone Numbers & Pegs

The ToneBox is based on the Chao tone number system, a pitch-based framework using the numbers 1 to 5:

• 1 = ˩ (Low)
• 2 = ˨ (Low-Mid)
• 3 = ˧ (Mid)
• 4 = ˦ (Mid-High)
• 5 = ˥ (High)

This allows us to describe the exact shape of a tone — whether it’s rising, falling, dipping, or level.

A tone written as 45 rises from mid-high to high, like the Thai word ม้า (māa) meaning 'horse'. A level tone like 33 stays at mid pitch. A falling tone like 51 drops sharply. This is the core of how tonal pronunciation is measured.

Try creating tones like:

• 21 — low to very low
• 213 — dipping
• 33 — level mid tone

Next we'll explore how to attach words to these tones to build memory and reinforce pitch-to-meaning relationships.