Many idol groups debut with 2 or more main vocals. In INFINITE, there is no doubt that Sunggyu and Woohyun, the two main vocals, are the vocal pillars of the team. 

While INFINITE boasts of vocally talented members with distinct vocal colors, including the rappers, Sunggyu and Woohyun have a different edge to them.

They do more than give the team two stable main vocals - their synergy and their complementary styles bring something fresh and spicy to the table when it comes to INFINITE's songs.

The Korean fans have nicknamed Sunggyu as 'cider vocal' and Woohyun as 'milky vocal', which sums it up pretty well. Sunggyu has a brighter, higher, and nasal sound with an amazing vocal range. His lower tones are cool but with a piercing quality, like rain. This is in juxtaposition to Woohyun's rich darker baritone that has a demure side to it. His lower tones sound more like clouds, fluffy but weighted at the same time.

This difference, this opposing forces of the two main singers' vocals, add a rich layer to INFINITE's songs. They make good use of the contrast between Sunggyu and Woohyun's vocals for a more sensational effect and the climax of the songs are left for them to draw out. A good example is the highlighted part of their song Voice of my Heart.

In a BEFF report by reporter Kim Joohyun on 'Analysis of INFINITE's vocals', it was mentioned that the complimentary quality of Sunggyu and Woohyun's voices has not gone unnoticed.

Translation: togetherinspirit7

Another memorable example is their Japanese hit DNA, where Sunggyu and Woohyun's voices boost each other to create a more dramatic effect when it comes to the chorus.

The other advantage the two explosive main vocals give the group is a nice meaty chorus. It usually falls upon the main singer to sing the chorus during live stages. Having the whole team sing the chorus is a dying art in Kpop songs these days as more and more composers are phasing them out. However, INFINITE, at least in their older songs, make use of powerful choruses, and Sunggyu and Woohyun's perfect teamwork and harmony sustain these choruses in live performances.

INFINITE V (Vocal), the unofficial subunit of INFINITE consisting of Sunggyu and Woohyun has not debuted yet but the few performances of them at concerts and fan meetings has everyone desperate for them to promote as a unit. This rendition of the INFINITE song, Between Me and You, at Sunggyu's solo concert has especially tugged at the fans' hearts as it shows the potential of a duet by these two.

They have also collaborated for an Immortal Song 2 stage, which was a treat for fans and anyone watching and shows both the contrast between their voices as well as perfect harmony!

These are rehearsed, planned. What really makes them the ultimate vocal soulmate is their ability to recreate their vocal teamwork and harmonize at a moment's notice, completely unplanned, without accompaniment. Perhaps it helps that they have sang together, side by side, practiced together, for years. Whatever the reason, their vocals are a match made in heaven!