A monitoring device (e.g., a ECG monitor or a Holter monitor) employing an electrocardiograph (40), and an ECG quality controller (50). In operation, the electrocardiograph (40) derives an electrocardiogram from one or more ECG leads (30) upon a connection of the electrocardiograph (40) to the ECG lead(s) 30 (e.g., electrode based or pad/paddle based). In response to the connection of the electrocardiograph (40) to the ECG lead(s) (30), the ECG quality controller (50) controls separate evaluations of a high-frequency noise level (e.g., a degree of muscle artifact and/or a degree of electrode motion artifact within the electrocardiogram) and a low-frequency noise level (e.g., a degree of baseline wander by the electrocardiogram) of an individual ECG lead (30) on an electrocardiogram segmentation basis (e.g., a continual ECG recording divided into segments of a specified duration).