In 1991, the band released their second album "Vital Signs 2". The album was a departure from the first album's more upbeat ways. The resulting sound emerging from such emotional turmoil and uncertainty was heavily melancholic and introverted ("Rahi", "Yaad Kerna"), suddenly jumping towards thumping anger with the powerful, "Aisa Na Ho". This was perhaps the most political album by the band. The album had more maturity, versatility and was a commercial success. This led the band to perform in the United States on a tour, thus making them the very first pop act to do so. The tour also changed the way the band looked, and the band saw the emergence of grunge and a revival of interest in '70s music, and became instigators of fashion. The change also saw Rohail, Shahzad and Junaid moving to Karachi (Rizwan decided to stay back in Islamabad), as Rohail started constructing a brand new studio in his Karachi apartment.