The Denon DA-300USB High Resolution Audio USB DAC and Headphone Amplifier is designed for audiophile personal listening from a Mac or PC personal computer, television, or home entertainment system. The DAC utilizes a PCM1795 D/A converter in a 32-bit asynchronous circuit to decode traditional pulse-code modulation (PCM) audio at up to 192 kHz as well as Direct Stream Digital (DSD) audio at 2.5 MHz and 5.6 MHz sampling rates.
For I/O, the unit features one USB type B port for connecting to a computer, two optical ADAT inputs, and one coaxial SPDIF input for connecting to a digital source such as an HDTV, DVD/Blu-ray player, game console, digital home receivers, and more. The unit utilizes two master clock crystals to optimize playback of the full range of broadcast sampling frequencies.
The circuit for the DAC incorporates Denon's Advanced AL32 processor to improve dynamic range and lower distortion. It also utilizes seven separate printed circuit boards (PCB) to improve isolation between circuit blocks with separate DC voltages delivered to each circuit stage from a 15V 1A AC/DC adapter. To further improve isolation, the circuit utilizes nine CMOS isolation chips with on-chip micro air core transformers to deliver 18 channels of isolation and improved common mode noise rejection.
In the output stage, the unit utilizes separate output circuits for the RCA line level outputs and for the 1/4" stereo headphone output. The RCA line level outputs send signal at 2V RMS which make them suitable for connection to pre-amplifiers, integrated amplifiers, and other analog audio components. The headphone amplifier circuit also includes a dedicated buffer, gain stage, and volume control so you can enjoy the DAC with a wide range of headphones, including low impedance models.
The DAC is controlled via a touch panel OLED display for cycling through the system's modes, sampling frequencies, and volume control. It can be positioned horizontally or vertically using the included custom bottom base plate.