Printing apparatus and nozzle testing method

A printing apparatus comprising:

• a head unit including a plurality of nozzles configured and arranged to discharge a liquid, a plurality of pressure chambers linked with the nozzles, and a plurality of piezoelectric elements respectively provided in each of the pressure chambers, the head unit being configured and arranged to discharge the liquid from the nozzles by applying a driving signal to the piezoelectric elements;
• and
• a control section configured to determine whether or not there is a liquid discharge failure in the nozzles corresponding to the piezoelectric elements based on a detection signal obtained by applying a testing waveform included in the driving signal to the piezoelectric elements,
• the control section being further configured to detect residual vibration using a first testing waveform in a first print mode performed at a first print speed, and to detect residual vibration using a second testing waveform in a second print mode performed at a second print speed with the first print speed being slower than the second print speed, a period of time for testing with the first testing waveform being longer than a period of time for testing with the second testing waveform.