This paper addresses various aspects on the realization of dedicated pulse-width modulation (PWM) based amplifiers for active loudspeaker systems, optimized in respect to energy consumption. A new amplifier concept, dedicated to woofer/: midrange (0-4.5-kHz) loads, has been developed. The concept is based on a novel feedback topology, a modulation strategy that is dependent of bandwidth and the use of a switching frequency as low as 44.1 kHz without compromising the sound quality. Detailed measurements on a 250-W example implementation are given. THD+N <0.1% is realized at all output powers and frequencies, and the reduction in energy consumption is around 90% compared with an equivalent conventional Class-AB amplifier.
Click to purchase paper as a non-member or login as an AES member. If your company or school subscribes to the E-Library then switch to the institutional version. If you are not an AES member and would like to subscribe to the E-Library then Join the AES!
This paper costs $33 for non-members and is free for AES members and E-Library subscribers.