Well, I sat down and tried to categorize the consonants cleverly to get good, comprehensible and analyzable spectrogram results. I decided to sort them into the main voiced [p, t, k, tʃ, f, θ, s, ʃ] and voiceless ones [b, d, ɡ, dʒ, v, ð, z, ʒ] of the English. It was a lot of (fun) work to record, extract and analyze and of course finally getting a god result:
Now, what are the striking differences?
It is obvious that the voiced consonants, contrary to the voiceless, show strong acoustic energy at a very low frequency (F1 is low): this corresponds to the vibrating of the vocal cords (UCL). Since the pronunciation of voiceless consonants does not involve vibrating of the vocal cords, we do not find this strong band at the bottom of their spectrogram. Another observation made is that the formants of the voiceless consonants seem to be more and more confused as the ones of the voiced consonants. This could prove that voiceless consonants are pronounced with more acoustic power or to put it unscientifically simple: they sound hard and more pressurized than their voiced counterparts: they sound softer and relaxed due to the vibration of the vocal cords. In German, we even say “scharfes s/sharp s ” and “weiches s/soft s” to refer to the voiceless and voiced /s/.
Feel voiced/voiceless consonants:
If you are not sure whether you are dealing with the voiced or voiceless variant of a sound, touch your neck/throat and make the sounds, e.g. /b/ and /p/: if you feel the vibration, it is a voiced consonant
Stay tuned because the next topic I’m preparing is Morphology!