in this video you will see class d amplifier comparation with linier amplifier and circuit study
recommend LCR meter https://www.amazon.in/dp/B07MRWCNQH/ref=cm_sw_r_cp_apa_glt_fabc_QDEBDXE5YQP1EKN42WCN
part 2 of this video https://youtu.be/Sk4kwAQA40Q