The difference between both [l] and [r] is what Korean people most wonder about in English pronunciation because both are heard alike to them. But looks like the difference was clarified when ‘the perfect edition of [r] in English’ was published on Bruce’s internet cafe (http://cafe.daum.net/blakeenglish) in 2009.
Both original sounds are as follows respectively.
[r] [( )]
Both original sounds are written very alike in HMJ phonetics. Also [r]’s original sounds contain [l]’s. So both are heard alike to Korean people.
Both [s] and [ɵ] in English and the pronunciation of ‘스’ in Korean have [스] in common as phonetic symbols in HMJ phonetics. Because their original sound is [스] ‘equally’. The difference among them is that their articulate point, articulate method, etc. are different from one another respectively.
In HMJ phonetics an articulate point, an articulate method, etc. are described saparated from a phonetics symbol(s). Because an original sound(s) is the most important in a certain sound.
– in the thesis of ‘Hoon Min Jung phonetics the second edition’
” [r] in English is the hardest pronunciation to people who speak English as a foreign language. But ‘Hoon Min Jung phonetics’ would analyze it perfectly in 2009 firstly in the world. Also, the difference of [r] in English, French and Spanish would be clarified firstly in the world in the thesis of ‘Hoon Min Jung phonetics the second edition'(http://www.scribd.com/hmjphonetics) in 2014.” – Bruce, the author-