This is generally accomplished by connecting your tonearm leads to the phono inputs of the DMC 20, and then connect the 20's tape outputs to a set of available line level inputs on the DMC 30. Leave the DMC 20 input selector set to phono with the tape output active (if switchable), and then when you select the connected input of the DMC 30 you will be listening to the phono stage of the 20 through the line stage of the 30.