M.C. The Max’s Vocal Analysis: Lee Soo

Vocal Range

G#2 ~ C#6 (3 octaves, 2 notes and 1 semitone)

Supported Range

F#3 ~ Eb4/E4

Voice Type



  • Extensive mixed voice range
  • Pitch is generally precise
  • Able to produce a sound that projects quite well
  • Has developed a part of his range with minimal tension
  • Sings with a dropped jaw allowing more space for his sound to project

Points for Improvement

  • Tends to sing straight from his throat
  • Sings with a lot of air pressure over compressing the vocal cords
  • Most of his range is sung with no support and tension
  • His mixed voice is generally pushed, tight and shouty
  • His head voice is mostly tense
  • His lower range lacks development and becomes breathy quite early on


  • Lower register: Generally quite breathy and underdeveloped. Sings without connecting his vocal cords nor supporting properly below F#3.
  • Mixed register: His most used register. Tends to stay in this range for most of his songs and has a quite extensive range in this register, however support is rarely ever present. Almost always sounds compressed and shouty, even as early as D4.
  • Upper register: His least used register, as he generally opts for staying in his mixed. He has sung quite high in his head voice, but tends to sing the same way he would in his mix; with over compressed and pushed air pressure and no true support.


As a rock singer, Lee Soo rarely ever sings songs that require any form of vocal agility. He is a vocalist who generally focuses on dynamics and range over vocal runs. As his influences are less geared towards R&B and genres that need runs, his vocal performances are focused more on singing in his mixed voice with power rock ballads. The few times he does attempt vocal runs, it’s possible to hear that he struggles to find the individual pitches for each note and slides generally off pitch, like in “고해.”

Overall analysis

Lee Soo debuted as the main vocalist of band Moon Child in 2000, when the K-pop scene was still being established and solo artists were more common, prior to idol groups. Although their initial debut wasn’t very successful, after the departure of one of the original members of the band, they renamed their band M.C. The Max and re-debuted as a trio. Lee Soo is one of the four most prominent male vocalists in Korea, being part of the “Four Vocal Kings.” The group is named 김나박이 (Kim, Na, Park, Lee), in alphabetical order, referring to each vocalist’s first name syllable: Kim Bum Soo, Naul, Park Hyoshin, and Lee Soo. They are all known for their legendary status due to their extensive vocal ranges, having all debuted around the same time and grown in success over the years as prominent male soloists. Each of them has influenced the way current idols sing, as Naul influenced many with more of an R&B flavor, whereas Park Hyoshin inspired many vocalists to adopt a more husky sound, while Lee Soo also inspired a lot of the high belting that’s very common amongst tenors in K-pop nowadays. More interestingly nowadays it seems people are also including Ha into the name, referring to Ha Hyunwoo, who currently holds the record for longest winning streak on King of Mask Singer.

Despite being recognized as one of the four best vocalists in Korea, when it comes down to vocal technique there is very considerable gap between Lee Soo and the other three vocalists. As he is greatly known for his extensive upper mixed voice range and his high notes, his lower range is a very neglected part of his voice. With barely any development, his chest voice is very under explored and thus the thyroarytenoid muscles aren’t very developed. As such, he tends to sing without much projection in his lower range, unable to maintain proper chest placement or support. His voice becomes breathy, soft and foggy quite early on, even as high as F3 such as in ““, where one can hear a clear lack of development in his chest voice muscles. This makes his chest voice possibly his least developed register overall. Examples of his chest voice lacking development include the Bb2’s and G#2’s in a low note battle with the other members of MC The Max, as well as the B2‘s and E3‘s in “사랑했지만,” and Eb3’s in “단 한번의 사랑.”

His mixed voice range is impressive in its extension. Although there is a clear lack of development of proper technique, his potential range is very extensive. This shows that had he developed his vocal cords properly, he would probably have an even larger range than what he currently uses. Unfortunately for many vocalists who debuted in the late 90’s and early 2000’s, including idol groups such as H.O.T., Shinhwa, Sechskies and G.O.D., they were all diamonds in the rough with a lot of potential but little to no understanding of proper vocal technique. Some have gone on to rework on their vocal technique and properly develop their voices, while others have not changed their vocal habits over the years at all and have been singing with unhealthy technique ever since their debut.

Lee Soo is no exception to this rule. When it comes to his mixed voice, he tends to overly compress his vocal cords together by keeping them very tight together while pushing a lot of air pressure from the diaphragm. When singing it is important to have a healthy balance between the amount of air being pushed from the diaphragm into the vocal cords while keeping a tight enough stretch of the vocal cords. However some vocalists teach themselves to push, not allowing the throat to stay as opened, so they over exaggerate the amount of stretch and air pressure and end up singing with a very shouty technique. This is exactly how Lee Soo sings. Healthy relaxed support is barely ever present in his voice. However since his mixed voice is well developed in range and is sung with minimal chest voice, he can push his range much higher than many vocalists with this technique. Arguably speaking, he is a gifted talent when it comes to his natural range. Nonetheless he is still a diamond in the rough even after all these years of singing with a very abusive vocal technique.

Thus whenever Lee Soo sings in his mixed voice, he tends to sound rather bright and considerably projected. However this is all achieved by singing with a high larynx and a pushed amount of air pressure, which causes him to sound pressed, tight and strained even as early as D4 in his mixed voice, as heard in “사랑했지만.” Below F#4 he may also at times push his larynx down, as heard in “붉은 노을.” As he sings higher, his voice starts to only become louder and louder. He shows a lack of ability to sing in his mixed voice without being loud, because his vocal cords have never been properly developed to mix in a healthy way, so due to the over excessive air pressure, he can only sing high when he sings loudly. The higher he sings, he tends to lower his jaw and allow the sound to project better, but he becomes shouty quite quickly. This can be heard with the Eb4’s and E4’s in “고해,” F4’s in “,” F#4’s in “Lonely Night,” G4’s in “잠시만 안녕,” G#4’s in “그대가 분다” and “붉은 노을,” A4’s in “그대는 눈물겹다” and “사랑했지만,” Bb4’s in “그대가 분다,” B4’s in “One Love,” C5’s in “그대가 분다” and “행복하지말아요,” C#5’s in “붉은 노을” and “그대그대그대,” and D5’s in “어디에도” and “그것만이 내세상,” and Eb5’s in “단 한번의 사랑.” The only range in which Lee Soo is able to sing with some form of relaxed support, although shallow, seems to be only up to Eb4/E4, as heard in “그대가 분다” and “행복하지말아요,” although the consistency is questionable due to his choice of pushing most of the time.

His upper register mostly consists of a head voice. He doesn’t often use this register but has shown that if he needs to sing softly within the fourth octave of the piano, he is able to switch into this register when unable to use his mixed voice. An example would be “행복하지 말아요.” Most of the time he avoids using his head voice, instead opting to sing as high as possible in his mixed voice. His head voice as he gets higher shows the same issues that he has in his mixed voice, over compressed air pressure. The higher he goes, he tends to attempt to emulate the sound of his mixed voice in his head voice, so he places his sound in the mask and pushes with more air pressure and a high larynx, becoming shouty and strained as he switches into his head voice. This can be heard in “잠시만 안녕” when he transitions from his mixed voice at D5, to F5, G5 and Bb5 in a very pushed and shouty head voice. His highest head voice to date is said to be C#6. Much like the rest of his range, support is barely present in this register as well.

His biggest asset aside from his extensive mixed voice range is his natural musicality. He knows how to use his voice dynamically and knows how to soften up his volume for the verses of his songs, while becoming very loud and emotionally climatic during the choruses and bridges of songs. Despite the unhealthy technique he uses, this seems to captivate most of his listeners and translates well into the average person’s perception of singing. Perhaps not the most technical vocalist out of all Korean legends, he still stays true to the essentials of Korean ballads and what it means to sing Korean music. The focus on dynamics and “emotions” is very important to the average Korean person, as well as big high notes during climaxes of songs. So he’s able to bypass his technical flaws by singing with what most people perceive as “emotion” in singing, which in other words can be called “dynamics” as well.

When it comes down to vocal technique, Lee Soo doesn’t quite fit well in the group of 4 big vocalists from Korea. He is not an example of healthy technique, nor an example of a well developed overall voice. However he does deserve the respect of many for his legacy and his artistry. Differently from many 90’s vocalists who have changed their technique, such as Park Hyoshin, who received backlash for not sounding like they originally did when they debuted, Lee Soo chose to stick to his musical roots. It would be advisable that he changes his technique before it’s too late for his voice when it’s damaged beyond repair, as singing Rock does not mean a vocalist has to sing in a unhealthy manner. Every genre can be sung in with healthy technique, all it takes is discipline and the willingness to change. Changing his approach would not affect his overall sound and would not interfere with his artistry, even if at first it may be hard to adjust to.


Lee Soo is more of a musical vocalist than anything else. He may at times add changes to his own musical compositions, but tends to stick to the original written melody of a song instead. He is always a lot more focused on singing softly during verses and allowing songs to grow into dramatic rock ballad climaxes throughout the choruses of his vocal performances. There is a clear preference for dynamics over musical changes in songs, they all seem to follow a specific formula that works for him and the musical image he’s built over the years.

Label (Type of Vocalist)

C Vocalists: Commercial Vocalists

Best Vocal Performance(s)

Vocal Range Video(s)

video by: 쌈자를 몰랑ᄏ ᄏ

Analyzed by Ahmin (Kitsunemale)


58 thoughts on “M.C. The Max’s Vocal Analysis: Lee Soo

  1. It always makes me cringe when veterans have poor technique lol
    Has he shown any signs of vocal damage? This reminds me of Christina Aguilera and how she is messing up her vocal cords.


    1. He lightened up his technique a bit over the years, so the damage hasn’t been obvious. He has strong vocal cords that can take abuse, it seems.

      Liked by 1 person

    2. I feel like a lot of veteran singers don’t have incredible vocal technique. Yoon Jong Shin I feel like is not the best vocalist, but he sure is a great singer though. Same with MC The Max! I still love them both~

      Liked by 1 person

  2. “Each of them has influenced the way current idols sing”
    Immediately thought of VIXX’s Ken he loves M.C. The Max and at times he actually sounds like Lee Soo especially when he sang Don’t Be Happy at KOMS. But whoa he’s actually better than his fave.


    1. Oh I was actually going to mention Ken, because when I hear Ken, the way he sings reminds me a lot of how Lee Soo sings but I wasn’t sure that it was a direct influence but now that makes me realize it’s more related than I thought.


  3. 1. Does Kim Bum Soo have a good technique like Naul and Hyoshin?
    2. He really reminds me of Ken from Vixx, Too bad. They both have underdeveloped lower register.


  4. As always, thanks for the analysis! I really admire the way you write. I find your ability to “look on the bright side” and find ways to compliment the artist on what they do well (even in cases such as this when their overall technique is so underdeveloped) to be quite admirable.

    Liked by 1 person

  5. Changmin still has a more extensive mixed range right? or at least shown it, I remember you saying he’s gone up to G5,


  6. Wow, I thought he would be up there in the rank, but his vocal technique is similar to JYP -__-
    3 down, only Kim Bum Soo left 😀


  7. At least he has a supported range lol it’s been a while since I’ve seen a weak rank singer without “N/A”. Also question, how good is Ha Hyunwoo?


  8. 이런 5.5, 1, 이런것도 있지만 제일 중요하는것 분석이잖아요. Rating말고 솔직히 말해서 분석 읽어보셨어요? 안그랬으면 욕하기전에 한번 읽어보세요. ^ ^


      1. Oh no I’m sure that’s got something to do with it, but if you can’t understand it, you can’t get mad about it. You’d have to understand it first and it’s not fair to cuss people out.


    1. Because we just felt it was like guess work and we can’t be 100% sure for pop vocalists and it’s partially irrelevant and unnecessary.


  9. I’m no musical expert, but I do think that Lee Soo’s voice has become a lot weaker/thinner over the years…if you look back to around 2007~ I think he was a much better singer and I notice that the link for best vocal performance is a much more recent video (maybe that influenced the score)? I do think, like you mentioned, perhaps his talent lies in his natural musicality—in any case thanks for the review!


    1. Best vocal performance videos don’t influence the final rating, they’re the best out of everything I was able to listen to. I disagree that he was better, if you check all the links in the analysis, you’ll see I watched videos from his debut up until this year and I did not notice a decline or a change in his technique, personally. No problem, thank you for reading!


      1. yes man.i did. I have to say that his vocal ability is decreasing now obviously, but he was a good singer in the past and also he will be a legendary singer in the future


  10. Hi!

    Thank you for the excellent analysis! Even though I’m a big fan of his music, I have to agree with you on the most of the points.

    I was wondering if you had a chance to check on his recording of Wie wird man seinen Schatten los? Here is a link:

    Unfortunately, there is no video of his live performance because he was pulled out of his part in the musical even before it began.. Anyway, can you tell he is using more proper vocal techniques here?

    Lastly, would you label his voice type as light lyric?

    Sorry for many questions 🙂


    1. Is this a studio recording? Just to be sure, cause I don’t hear any audience noise and his voice is very clear. I would probably lean more towards a light lyric for him if I had to choose, yes. 1:00 The chorus starts and he is using some throat to push the Eb4’s, 1:20 G#4’s, definitely high larynx and pushing up here. So there’s a degree of slightly better placement and slightly less pushing but it could also be cause this isn’t a live recording. Personally I believe it’s about the same as his best technical moments that I’ve heard so far. 2:37 F#4 too, I hear the high larynx there. Even F4’s, I do hear the same issues I usually hear but this studio recording does make him sound better than his pop songs for some reason. The pushing isn’t as obvious because I believe he’s singing mostly lower. In his pop songs he likes to constantly go up to C5, so there’s more room for tension to be apparent.


      1. Yes it is a studio recording. Sorry I wasn’t very specific. Sadly, he never made to the actual stage. A number of people were against him being the lead part and tried to boycott the musical. In the end, the director canceled ISU’s casting…

        Can I ask you one more question? Which note do you think ISU’s first passiggi is located at? Some people say his tessitura is arguably contralto’s, which is a bit higher than tenor’s. Would you agree with that to a certain degree?


      2. Oh that is so stupid! I mean I’m sure people didn’t boycott cause of his singing ability cause Korea thinks he’s amazing but probably cause.. of some probably stupid reason. I don’t agree no. I think he’s just a tenor who sings light so he sounds like his passaggi are higher. I’m not sure exactly what note but I’m sure it’s not a contralto’s tessitura since women’s passaggi are much further apart.


      3. I think they boycotted because he had the scandal where he had sex with an underage prostitute. I think they found in the case that he was unaware that she was underage or something like that, but a lot of the musical fans didn’t want him in it since the role of Mozart has a lot of work with child actors and the musical fans weren’t comfortable with him on the show because of that. I think any time he ever tried to be on show or tv since he was cut, even in music competition shows like I am a Singer. I guess people just want him to only sing and do concerts which is understandable.


  11. Nice analysis. Though I’m a big fan of Isu, I do agree with your analysis of his weaknesses (which is written at ‘Points for Improvement’ part). Thank you.

    Liked by 1 person

  12. You wrote ”Has developed a part of his range with minimal tension” what does that mean? That he is singing healthy or without damaging his vocal chords. Could you explain more pls.


    1. Considering the way he sings, I’ll assume that means “singing in way that is least damaging to his vocal chords”. Lee Soo is just too throaty and strains too often that his style cannot be considered “not damaging”

      Liked by 1 person

    2. Yes there’s a small part of his range where there’s minimal tension, which I’m sure I went into more detail in the overall analysis.


  13. You are freaking a technique snob.
    “he’s able to bypass his technical flaws by doing the bare minimum of what most people perceive as “emotion” in singing.” 말하는 꼬라지 봐 ㅋㅋ

    Technique isn’t everything in pop dude. Just stop analyzing singers and go upload videos about how good ur technique is.

    Liked by 1 person

    1. This is a blog about vocal technique to educate those interested in learning more. If what you want is to have your opinion validated and not learn anything new, then I do apologize that this isn’t what we are here to do. You come to a blog about vocal technique to complain that technique isn’t everything, it’s like me going to a blog about language grammar saying “you’re a freaking grammar nazi. Grammar isn’t everything.” Can you see how that doesn’t make sense? I’m not sure what you were trying to accomplish by being here complaining about what the whole purpose of the blog is. ._.

      Liked by 4 people

      1. What I meant was, You are not only talking about his techniques but also discrediting his career. Like I mentioned above, “he’s able to bypass his technical flaws by doing the bare minimum of what most people perceive as “emotion” in singing.”, Do you really think this is a necessary sentence when we are talking about the techniques? No, I don’t think so.That is almost like an insult to Kpop listeners or people who like Lee Soo.


      2. People like to mention emotion as part of vocal technique as if it was something measurable, when it’s not. That sentence is supposed to give reasoning to what people listen, since might feel as though “well I still like his singing” and that sentence is basically explaining why his fans would like his singing, matter of factly. I’m not sure how it’s an insult. Since he has limitations in his technique, it limits his dynamics, thus limiting how well he could deliver what most people perceive as emotion. He sings high with volume, which many people call emotions which is what I called the bare minimum. Does that better explain my intentions behind that sentence? He’s unable to sing high softly, to control his mixed voice as he gets higher without getting louder, he has too much air in his voice, his lower notes lack development, all of which limit his ability to further emote in his voice. Do you see where I’m coming from? You’re focusing on a single sentence of the analysis, instead of the whole of the analysis. If my intentions were to insult Lee Soo, I’d have been an immature writer and just straight up bashed him which again is not what this blog is about. If it means so much to you, I don’t mind changing that sentence because what matters to me is the whole of the analysis, not this one single sentence. I just defended why I believe it’s a relevant sentence in the context of technique, but it can be removed if you’d like. I’m not sure how it’s an insult or even discrediting his career.

        Liked by 2 people

    2. “Technique isn’t everything in pop dude.”

      이건 무슨 말도 안되는 논리로 불평하고 있네 ㅋㅋㅋㅋ ㅁㅊ. Last time I checked, SINGING is the job of professional SINGERS and in order to do so, you need to have good technique. 발성법이 모든 노래의 기초다. In a comparison, why don’t you try telling pro athletes that “technique isn’t everything?” When they lift weights, would you rather sacrifice a good form and risk injury just to lift as much as you can with terrible form?

      Liked by 5 people

      1. 한국분인거 같으니 한국말로 적을게요
        운동선수로 예를 드셨으니 저도 운동선수로 예를 들어보죠
        우사인 볼트 선수가 세계에서 가장 빠른 선수였던건 아시겠죠
        그 선수는 “정석”적인 달리기 선수의 특징이 거의 없습니다
        키가 평균보다 훨씬 큼으로서 다른 선수들 보다 바람의 저항이 크다는점,
        다른 선수들과 다르게 긴다리와 큰 보폭, 또 그 긴 다리와 척추 측만증으로 인해
        다른 선수들과 특이한 달리기 자세 그럼에도 불구하고 세계에서 최고로 빠른 남자가 됐죠. 정석으로 하는게 제일 잘하고 젤 빠른게 아닙니다
        가수도 마찬가지죠 발성이나 테크닉만 좋다고 노래를 다 잘합니까? 김광석이나 김현식이 발성이 좋아서 좋은가수로 평가 받습니까? 발성에만 얽매여서 가수의 평가를 까내린다? 주객전도죠 까놓고 얘기해서 이글 쓰는새끼 지가 하는말이 진리 마냥 가수들 평가질 하는게 존나 띠껍네요 ^^


      2. @Chris

        타고난 신체적인 조건과 배울수 있는 테크닉은 두 개의 천차만별 요소들입니다. 우세인볼트의 신체적인 조건을 예를 드셨으니 저도 성악가들 그 분야로 예를 하나 들죠.남자 성악가들 중에서도 흉성근육이 굉장히 약해 저음과 벨팅이 잘 안되는 테너들은 두성으로 노래하는 카운터테너로 성종을 바꿉니다. 이분들도 고음을 “일반적인” 테너들의 벨팅과 달리 두성으로 올리지만 그래도 훌륭한 경력을 따내죠. 우세인볼트처럼 어떻게 보면 정서적인 테너들에 비해 불리한 조건을 타고났어도 방법을 찾는거죠. BUT, 노래나 운동 둘 다 몸으로 하는 겁니다. 달리기도 바람의 저항때문에 다리 뿐만 아니라 강한 상체와 허리 힘을, 그리고 올바른 테크닉 요구하지요. 노래할때 두 사람이 같은 고음을 내더라도 올바른 발성을 쓰는 자가 훨씬 더 쉽게 내듣이.

        마지막으로 전 개인적으로 발성법 좋은 가수 들이 인식을 받지 못하거나 오히려 까이고 (예를 들면 소향 같은 경우는 너무 고음만 “지른다,” 사실은 완벽함에 가까운 발성으로 노래 하지만), 이수, 임재범 같은 생목으로 노래하는 가수들이 그놈의 “감정” 때문에 더 좋은 평가를 받는게 마음에 걸립니다. 그리고 이 글 쓴 ahmin은 보컬 강사로서 우리같은 일반인들보다 더 해박한 지식을 가지고 객관적으로 가수들의 발성만 가지고 평가하는게 그게 왜 “띠꺼운지” 모르겠네요. 이 사이트 소개하는 창을 읽어보셨다면 순수한 발성으로 분석하는 건데 그게 문제되시고 못 받아들이시겠다면 다시 오지 마세요 🙂

        Liked by 1 person

  14. I think these analysis are really funny and correct. I have Youtube channel discussing about singing tips. Can you allow me to translate these articles in Korean and read in my Youtube channel?


    1. 한국분이시죠? 번역해주셔도 괜찮을 것 같은데 혹시 모르는 단어나 영어에서 한국어로 어떻게 번역해야 되는지에 대해 궁금한 거 있으시면 꼭 저한테 물어보면 됩니다. 제가 보통 neutral 입장에서 쓰는 거라서 번역할 때 그렇게 번역해줬으면 좋겠습니다.


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