Denon PMA-1520 (1988)

Type: Integrated amplifier
Dynamic power: 300 W/ch (8 Ω), 400 W/ch (8 Ω) — per HiFi/Stereo test
Key feature: Optical Class A output stage; DIGITAL DIRECT input bypass

Documentation on the PMA-1520 is thin. What we know comes almost entirely from a single test report in HiFi/Stereo (July 1988, p.35). The same review noted dynamic power ratings of 300 and 400 watts per channel into 8 ohms. That suggests healthy headroom for a mid-1980s integrated.

The PMA-1520 used Denon's "Optical Class A" output stage. It was a bias scheme that kept the output transistors conducting a small standing current at low signal levels (effectively Class A) and shifted to a more conventional mode as level rose. Inside, the chassis was divided into separately shielded compartments for the digital and analog sections. A front-panel DIGITAL DIRECT button let the amplifier bypass its normal input switching and tape loops and route a digital source straight to the power amp stage. It is conceptually similar to the more common CD DIRECT found on other Denon integrateds of the era.

The review described the PMA-1520 as priced competitively with similarly rated amplifiers, though no exact retail price was stated. Beyond that listing in HiFi/Stereo, no catalog pages, service literature, or subsequent reviews have surfaced.