Ringtone Monophonic have a different form in writing, depends on kind or type of its mobile phone. For example for Siemens c1(1/16) d1(1/8) but for Nokia 16c1 8d1 so, to input the ringtones from Siemens mobile phone to Nokia mobile phone needs a converter. Deterministic Finite Automata (DFA) from language and automata theory with logical method can be used to convert ringtone which DFA will be used to check the ringtone that had been
entered (it can be compose by own or open it from a text file) and logical method is used for changing pattern or writing ringtone between different kinds of mobile phone by changing and fiting the writing pattern of the tap, octave and source ringtone to be writing pattern of the tap, octave and target ringtone through the iteration process as much as the ringtone had been entered. Finally, this research software can be used to convert and compose the ringtone for four different types of mobile phone such as Ericsson, Nokia, Samsung and Siemens.