Whenever any direct or indirect representation is made of the power output, power band or power frequency response, or distortion characteristics of sound power amplification equipment, the following disclosure shall be made clearly, conspicuously, and more prominently than any other representations or disclosures permitted under this part: The manufacturer's rated minimum sine wave continuous average power output, in watts, per channel (if the equipment is designed to amplify two or more channels simultaneously) at an impedance of 8 ohms, or, if the amplifier is not designed for an 8-ohm impedance, at the impedance for which the amplifier is primarily designed, measured with all associated channels fully driven to rated per channel power. Provided, however, when measuring maximum per channel output of self-powered combination speaker systems that employ two or more amplifiers dedicated to different portions of the audio frequency spectrum, such as those incorporated into combination subwoofer-satellite speaker systems, only those channels dedicated to the same audio frequency spectrum should be considered associated channels that need be fully driven simultaneously to rated per channel power.

In addition, whenever any direct or indirect representation is made of the power output, power band or power frequency response, or distortion characteristics of sound power amplification equipment in any product brochure or manufacturer specification sheet, the following disclosures also shall be made clearly, conspicuously, and more prominently than any other representations or disclosures permitted under this part:

The manufacturer's rated power band or power frequency response, in Hertz (Hz), for the rated power output required to be disclosed in paragraph (a) of this section; and

The manufacturer's rated percentage of maximum total harmonic distortion at any power level from 250 mW to the rated power output, and its corresponding rated power band or power frequency response.