A transport spins the CD and reads the digital data off the CD media. This digital data stream is then sent to an external "digital-to-analog converter" or DAC for short. The DAC converts the digital data stream into a line level analog signal that is then fed to your preamp or integrated amp.
So a transport can be thought of as a CD player minus the DAC electronics. CD players have the DAC circuitry built-in while a transport uses an external DAC.
So a transport can be thought of as a CD player minus the DAC electronics. CD players have the DAC circuitry built-in while a transport uses an external DAC.