F.T. Island detailed their recent comeback on the August 5 airing of 'Sketchbook,' talking about why they opted for a hard rock sound and the song-making process under Hongki's production team Hong's Tower. 

Hongki explained, "I didn't know that our sound would become so heavy. There was a rough sort of feel [to the songs] before the editing process, but as we worked on them, they became heavier. It sounded awesome so we decided to stick with it." 

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Hongki also talked a bit about Hong's Tower, the production/song-composition team he himself formed and organized. He said, "There used to be seven people [on the team] but now there are four. Jaejin recently left the group." Jaejin, put on the spot, justified his leave with, "If you want to be a part of Hong's Tower, you have to pay the monthly rent to use the recording studio but it was too expensive so I just left." 

F.T. Island concluded their talk by expressing their desire to continue doing music even when they're above the age of 50, adding, "We hope that the band scene [in Korea] will rise again and that music will become more diverse."