Only one I’ve seen do this is Miller Audio Reasearch Test Labs, when they did 3rd party Lab Report testing for HiFi News and Record Review, like they did on the Wilson Alexia, which managed an EPDR of just 0.9ohm!!!! in the bass.Ha George, My Watt 3's went one better 0.75 Ohm!
https://www.absolutesounds.com/pdf/main/press/WA%20Alexia%20HFN%200313-4web.pdfCheers George
Class D seems to work better than Class AB in Power regeneration Products though.
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