Mr Hall, 84, is accused of committing a string of historic sexual offences against his alleged victims.
He will go on trial at Preston Crown Court on May 6.
Mr Hall, of Wilmslow, Cheshire, is alleged to have committed seven counts of rape against one complainant between 1976 and 1978 in Manchester. Five of the rapes are said to have taken place when she was aged under 16.
He is also accused of two counts of indecent assault against the same complainant within the same period.
In addition, he is charged with eight counts of rape against a second alleged victim between 1976 and 1981, at various locations in Greater Manchester and Cheshire.
One of those alleged rapes is said to have taken place when the complainant was aged under 13.
Mr Hall is also accused of three counts of indecent assault against the same alleged victim.
Answering to his full name of James Stuart Hall, the defendant entered not guilty pleas to each of the 20 counts.
The trial is estimated to last seven days.