Melodic Death Metal
Melodic Death Metal (also referred to as Melodeath) is a musical subgenre of Death Metal. As the name suggests, it is more melodic; it has more emphasis on melody and harmonic techniques, is less brutal and has a greater incidence of guitar solos than its “original genre”. Some bands even use the keyboard – very rare in Death Metal, like The Children Of Bodom with Janne Wirman.
Furthermore, many vocalists sing with clean vocals in parts of some songs instead of exclusively guttural vocals, like in Death Metal.
The precursor bands of this metal genre were Therion, Carcass, Arch Enemy, In Flames, Dark Tranquility, At the Gates, Children of Bodom and Soilwork.
Extreme Power/Speed Metal
There is a great debate among metal lovers about cases of bands like Children of Bodom, Amon Amarth, Norther and Kalmah, who make a sound that some call melodic Death Metal, while in contrast, others call Extreme Power/Speed metal, that is, a mix of Power Metal and Speed Metal, only heavier and with the use of guttural vocals or ripped vocals.
One of the arguments of those who defend this term for Children of Bodom is that there is a great similarity between this and Power Metal bands such as Stratovarius and Sonata Arctica. Personally, I do not agree because you would need to take also in consideration the style of the band and lyrics, themes and Children of Bodom do not fit in Power or Speed despite Alexi’s fast power solos.