I am trying to understand the working of an old computer speech synthesizer (SAM for the commodore64) which uses a series of rules to break English text into a string of phonemes. The rules make some frequent tests for membership of the following letter sets:
// 0x04 [ D J L N ] // 0x08 [ B D G J L M N R V W Z ] // 0x10 [ C G J S X Z R S T Z ]
Is anyone able to spot what traits the following sets may have and why they are significant?
Would I be correct in thinking the 0x10 set are fricatives?
Thanks in advance for any insight you can provide.