ANSI CTA-2031-2008 pdf download Testing and Measurement Methods for Mobile Loudspeaker Systems
4.3.1.1 Test Conditions and Equipment The DUT shall be tested in free air in accordance with the test procedures for power compression, distortion and accelerated life described in ANSI/CEA-426-B. If it is desired to report a secondary rating that is based upon testing in a sealed enclosure then the above test may be repeated with the low frequency driver mounted in a manufacturer-recommended enclosure.
4.3.1.2 Displacement Limit The manufacturer shall specify the maximum excursion (one-way or peak-to-peak) of the device that, when exceeded, results in permanent mechanical damage to the device.
4.3.1.3 Statistical Study The manufacturer shall assure sufficient statistical study of a given class of product to establish a rated power.
4.3.2 Enclosure Specifications The manufacturer shall specify for a given driver the recommended enclosures or enclosure type. The manufacturer shall also note any differences in the rated power of a low frequency device if its performance in a given enclosure is significantly different from that observed with the unit mounted on the standard baffle to radiate into 2π steradians.
4.3.2.1 Additional Power-Handling Information If the rated power for a given low frequency driver/enclosure combination is different from that observed when the driver is mounted on the standard baffle to radiate into 2π steradians, the manufacturer shall so state.
5 Associated Amplifier Power Loudspeaker ratings obtained using this standard shall be specified for a specific amplifier power measured in accordance with CEA-2006-A. 6 Sensitivity For subwoofers, a calibrated microphone shall be used to perform a near field measurement of the sound pressure level (SPL) of the DUT when the DUT is operating with one Watt of input power at the center of its published operational bandwidth, or 50 Hz. (See 9.2 for an explanation of near field measurements.) For all speakers other than subwoofers, a calibrated microphone shall be used to measure the SPL of the DUT at one meter when the DUT is operating with one Watt of input power referenced to an appropriate voltage level at the nominal impedance (see section 7) at the center of its published operational bandwidth.