Disc-shaped information carrier provided with two portions having different read-out speeds

A disc-shaped information carrier (1) with a substrate (3) and an information layer (5) which comprises optically readable elementary marks having a substantially uniform density. The information layer (5) comprises a first portion (11) suitable for being read out at a first read-out speed and a second portion (13) suitable for being read out at a second read-out speed higher than the first read-out speed. According to the invention, the second portion (13) of the information layer (5) is at a greater distance to a center (7) of the disc-shaped information carrier (1) than is the first portion (11) of the information layer (5). A range of rotational speeds which an optical read-out unit must have for a full and correct read-out of the information carrier (1) is reduced in this manner. In a special embodiment, the first portion (11) of the information layer (5) comprises a first version of an audio recording provided on the information layer (5) by the DSD transformation method, whereas the second portion (13) of the information layer (5) comprises a second version of this same audio recording provided on the information layer (5) by the PCM transformation method.