An ultrasonic system for atherectomy procedures, the system comprising: an ultrasound signal generator configured to generate an ultrasound electrical signal; an ultrasonic treatment device electrically coupled the ultrasound signal generator , the ultrasonic treatment device having an ultrasonic transducer drivably coupled to an ultrasonic vibration transmission member (28-2) of an ultrasonic catheter, the ultrasonic transducer receiving the ultrasound electrical signal to generate an ultrasonic vibratory motion of the ultrasonic vibration transmission member (28-2) ; circuitry configured to monitor an electrical characteristic associated with the ultrasonic transducer , the electrical characteristic being one of a total voltage across the ultrasonic transducer, a total current to the ultrasonic transducer, an induced current of the ultrasonic transducer, or a Power Factor between the total voltage and the total current, the circuitry including a processor circuit (20-1) configured to process the monitored electrical characteristic to determine at least one of a type of material encountered by a distal end of the ultrasonic vibration transmission member (28-2) and a type of vascular pathway that the ultrasonic catheter is traversing, the circuitry configured to generate a control signal that is supplied to the ultrasound signal generator to automatically control at least one of a modulation frequency and a waveform of the ultrasound electrical signal based on the determined at least one of the type material encountered by the distal end of the ultrasonic vibration transmission member (28-2) and the type of vascular pathway that the ultrasonic catheter is traversing. an ultrasound signal generator configured to generate an ultrasound electrical signal; an ultrasonic treatment device electrically coupled the ultrasound signal generator , the ultrasonic treatment device having an ultrasonic transducer drivably coupled to an ultrasonic vibration transmission member (28-2) of an ultrasonic catheter, the ultrasonic transducer receiving the ultrasound electrical signal to generate an ultrasonic vibratory motion of the ultrasonic vibration transmission member (28-2) ; circuitry configured to monitor an electrical characteristic associated with the ultrasonic transducer , the electrical characteristic being one of a total voltage across the ultrasonic transducer, a total current to the ultrasonic transducer, an induced current of the ultrasonic transducer, or a Power Factor between the total voltage and the total current, the circuitry including a processor circuit (20-1) configured to process the monitored electrical characteristic to determine at least one of a type of material encountered by a distal end of the ultrasonic vibration transmission member (28-2) and a type of vascular pathway that the ultrasonic catheter is traversing, the circuitry configured to generate a control signal that is supplied to the ultrasound signal generator to automatically control at least one of a modulation frequency and a waveform of the ultrasound electrical signal based on the determined at least one of the type material encountered by the distal end of the ultrasonic vibration transmission member (28-2) and the type of vascular pathway that the ultrasonic catheter is traversing. <EOS>