Taiwan Min Nan (Taiwanese) checked tones sound change

The multifaced changes of Taiwan Min Nan (TMN) checked sandhi tones, S3 and S5 were investigated as well as the checked base tones, B3 and B5. Simultaneous EGG data, CQ_H and acoustic data, including duration, f0 offset at 80% vowel interval, and spectral tilt H1*-A3* from forty male and female speakers above 40 and under 30 years of age were analyzed. Though different measures progress at different paces, in general, as the coda stops [p, t, k, ?] from full stop closure, to energy damping and finally to complete deletion, vowel duration lengthening, f0 offset lowering, and more modal phonation were observed. Gender effects were found on f0 offset and CQ_H offset. The pace of progress is more advanced for base tone B5 with glottal coda stops. After coda deletion, the contexts conditioning the anticipatory co-articulation were removed and vowel and tone characteristics were modified to be similar to those found in open syllables.