CEI EN IEC 60268-21

This part of IEC 60268 specifies an acoustical measurement method that applies to electro-acoustical transducers and passive and active sound systems, such as loudspeakers, TV-sets, multi-media devices, personal portable audio devices, automotive sound systems and professional equipment. The device under test (DUT) can be comprised of electrical components performing analogue and digital signal processing prior to the passive actuators performing a transduction of the electrical input into an acoustical output signal. This document describes only physical measurements that assess the transfer behaviour of the DUT between an arbitrary analogue or digital input signal and the acoustical output at any point in the near and far field of the system. This includes operating the DUT in both the small and large signal domains. The influence of the acoustical boundary conditions of the target application (e.g. car interior) can also be considered in the physical evaluation of the sound system. This document does not assess the perception and cognitive evaluation of the reproduced sound and the impact of perceived sound quality.

NOTE Some measurement methods defined in this document can be applied to headphones, headsets, earphones and earsets in accordance with [1]¹. This document does not apply to microphones and other sensors. This document does not require access to the state variables (voltage, current) at the electrical terminals of the transducer. Sensitivity, electric input power and other characteristics based on the electrical impedance will be described in a separate future standard document, IEC 60268-22, dedicated to electrical and mechanical measurements.

¹ Numbers in square brackets refer to the Bibliogaphy.