The judges' auditions were held on selected dates and locations in a number of major cities of Australia, and were broadcast over the first few weeks of "The X Factor". The show was open to solo artists and vocal groups aged 14 and above, with no upper age limit. Only a selection of auditions in front of the judges were broadcast, usually the best, the worst and the most bizarre. During the first season of "The X Factor", each act entered an audition room and delivered a stand-up unaccompanied performance of their chosen song to the judges, without any instrumental music playing. During the bootcamp stage (formerly lock down in season 1, and super bootcamp in seasons 4–6), each judge was assigned one of the four categories to mentor. It was usually held on three days. In seasons one, two and three, each judge was given 24 acts and had to decide on their 12 acts after day two, and their six acts after day three. Each judge was assisted by a celebrity guest judge who would help them choose their acts. In season one, the judges narrowed down their acts to five instead of six. In seasons four, five and six, all four judges worked together to collectively choose 24 acts (six from each category) for the next round, home visits, where they find out which category they will mentor. From season seven, bootcamp were now based around the five seat challenge, where each judge chose their five acts to go through to the super home visits. From seasons two to six, the super home visits stage (formerly judges' houses in seasons 1–2, and home visits in seasons 3–6), saw the judges and their remaining six acts travel to four different places of the world. From season seven, all four judges and their remaining five acts traveled to the same location. During the super home visits, each act performed one song in front of their mentor and celebrity guest judges. Afterwards, each mentor and their guest judges narrowed down the acts to three for the live shows. The finals consisted of two live shows, the first featuring the contestants' performances and the second revealing the results of the public voting, culminating in one/two acts being eliminated each week. The live shows were filmed at Fox Studios in Sydney. In season one, the shows were filmed at Hisense Arena (formerly Vodafone Arena) in Melbourne. In season two, the live shows were broadcast on Sunday and Monday nights, but moved to Monday and Tuesday nights for seasons three and four. In season five, the live shows returned to Sunday and Monday nights.