Suppose you make a tape recording of a male voice singing slowly and playing it back at double speed.
What will happen to the pitch of each note?
What will happen to the formant frequencies of the vowels?
Will it merely sound like a woman singing fast?
Same
When you play back a tape recording at double speed, the pitch of each note will be increased by one octave. This means that all the notes will sound higher than the original recording.
Formant frequencies refer to the resonant frequencies produced by the vocal tract during vowel sounds. When you play back a recording at double speed, the formant frequencies of the vowels will also increase. This can lead to a perceived shift in the timbre of the voice, making it sound thinner or brighter compared to the original recording.
It is important to note that simply playing back a male voice recording at double speed will not make it sound exactly like a woman singing fast. Although the pitch will be higher, the overall sound characteristics such as vocal quality, pitch modulation, and articulation will still remain distinctive to the original male voice.
When you play back a tape recording of a male voice at double speed, several changes occur that affect the pitch and the formant frequencies of the vowels.
1. Pitch of each note: The pitch of each note will be raised. This is because playing the recording at double speed shortens the time interval between each successive sound wave, effectively increasing the frequency and raising the pitch. For example, if a note is originally recorded at 100 Hz, playing it back at double speed would result in a pitch of 200 Hz.
2. Formant frequencies of the vowels: The formant frequencies of the vowels will also change. Formants are resonant frequencies that give each vowel its unique quality. When you speed up the playback, the formant frequencies will increase along with the pitch. As a result, the vowel sounds may become higher and different in character compared to the original recording.
3. Perception of a woman singing fast: Although the pitch and formant frequencies change when you play back a male voice at double speed, it might not necessarily sound like a woman singing fast. The altered pitch and formants may result in an unnatural and unfamiliar vocal quality. It is more likely to sound like a high-pitched, fast-paced, and distorted version of the original male voice.
To gather more insights and specific examples, you can experiment with a sound editing software that allows you to change the speed or pitch of an audio recording. This will help you visualize and audibly perceive how the changes affect the pitch and formants.