Class D is the future of amplification, a Technology that is evolving and making class AB amplification become obsolete
Look at NAD new Class D technologies
Denmark’s Purifi Audio. Purifi’s load-invariant design provides wide, flat frequency response, even into challenging loudspeaker loads. Noise, harmonic distortion, and IM distortion are virtually unmeasurable at all frequencies and output levels. Another benefit of the Eigentakt™ design is extremely low output impedance and correspondingly high damping factor
We may eventually see these technologies drip down to ""FRFR"" cab applications