The Marantz HD-AMP1 sits within Marantz’s compact HD series, designed to deliver reference-grade performance in a smaller chassis than the brand’s traditional full-width components. It combines a high-resolution DAC section with an integrated amplifier and a dedicated headphone stage, making it equally suited to desktop and traditional hi-fi use.
DAC and digital architecture
The digital section is built around an ESS SABRE ES9010K2M DAC, paired with Marantz’s Musical Digital Filtering (MMDF) and a dual crystal clock for reduced jitter. The rear USB-B input operates in asynchronous mode with galvanic isolation, accepting PCM signals up to 384kHz/32-bit and DSD streams at 2.8, 5.6 and 11.2 MHz. Optical inputs (x2) and a single coaxial input handle PCM up to 192kHz/24-bit. A front-panel USB-A port provides direct connection for Apple devices.
Analogue stage and amplification
The analogue output stage uses Marantz’s proprietary HDAM-SA2 discrete current-feedback modules in the DAC post-filter, maintaining a short signal path with minimal active components. The power amplifier section delivers 35W per channel into 8Ω (20Hz–20kHz, 0.1% THD+N) and 70W dynamic power into 4Ω, with a quoted signal-to-noise ratio of 105 dB and harmonic distortion of 0.05% at 1kHz. Two gold-plated RCA analogue inputs are provided alongside the digital connections.
Headphone amplifier
The front-panel headphone output includes a three-position gain switch (low, mid, high) and independent volume control, allowing the HD-AMP1 to drive headphones ranging from low-impedance in-ears to high-impedance audiophile models. A ground isolator function is available in DAC mode to reduce ground loop noise when connected to a computer.
Construction
The chassis features a solid aluminium front panel with a double-layered bottom plate for vibration damping, and Marantz’s retro-styled side panels. Speaker connections use Marantz’s SPKT-1 terminals, compatible with speakers rated between 4 and 16Ω. D-Bus connectivity is included for system integration with other Marantz HD-series components.