The spelling of the word "bluth" may seem confusing, but it is easily explained through the International Phonetic Alphabet (IPA). The "bl" sound is represented by /bl/, with the "b" being voiced and the "l" being a lateral consonant. The "u" uses the IPA symbol /ʊ/, which represents a short u sound. Finally, the "th" is a voiceless dental fricative, represented by /θ/. Therefore, the correct pronunciation of "bluth" is /blʊθ/.