Possible Clues:

• Hit in inner ring of dartboard
• More than twice as high as 1 across?
• Go from 3 to 9, say
• Boy's voice
• Triple - soprano voice
• Triple - high-pitched
• More than two times as high, by the sound of it
• And that's even more than twice as high
• Three times - a boy soprano
• Threefold; boy's voice