CLASS DEVOLUTION

摘要

New Class D implementations are arriving thick and fast these days and they are offering a real alternative to the topologies of the 'old guard', including B&O's ICEPower and the Far Eastern Flying Mole series of amplifiers. The new wave of load-tolerant analogue Class D designs really began with Bruno Putzeys' UcD (Universal class D) technology which was developed at Philips' Applied Technologies Lab. Philips holds the patent to UcD but its advantages are realised in practice by the Hypex modules [see www.hypex.nl and Acoustic Imagery HFN Jan '12]. Anthem's bespoke Class D technology, with its feedback placed after the output filters, delivers a performance that's closer to Primare's UFPD circuit employed in the 132 [HFN Jun '11]. Like the 132, the Ml maintains a consistently flat frequency response regardless of the speaker load. Moreover, thanks to its switch mode power supply (with power factor correction), the Ml is also able to drive these low and variable loads with complete confidence.