Achieving Natural Fluency using a Metronome based approach
Citation
(2016) Achieving Natural Fluency using a Metronome
based approach, no. 45.
Abstract
This study investigates person's ability to entrain to a stressed metronome to see if
this produces fluent and natural speech. The concept of a stressed metronome is
unexplored in current research. The literature shows that speaking one syllable on
and syllable off to a metronome results in highly fluent, however also highly
unnatural speech. This study aims to examine stressed syllable entrainment at three
different speech rates to look at the effect this has on the speech naturalness
ratings.
Three different metronome rates in beats per minute were established to compare
the effect they have on speech naturalness. A baseline speed was determined from
the average of ten participant's speech rates. The fast and slower rates were
determined from a method used in a previous study Twenty participants were
recorded reading the stressed syllables highlighted in a passage to the metronome
beat. The audio files were saved on a computer and analysed by studying the
acoustic and provided waveform displays of the speech using PRAAT. Overall
speech rate of each recording and the distance between onset of stressed vowels
were analysed to determine entrainment at a gross and precise level. The overall
speech rate was determined from where the speech signal began and ended. The
distance between vowels were annotated and specific intervals in the speech data
were marked. The recordings were then listened to and rated by naïve listeners on a
5 point scale.
The Results show that overall, speakers can entrain to a stressed-timed metronome,
on both a precise level and gross level. However, this does not increase naturalness
of speech in all conditions.
To conclude, a possible combination of syllable-timed and stressed-timed
entrainment could be an effective method. This is the first step in a process to
devising a method to achieve naturalness of speech and fluency simultaneously.