Advanced DAC Architecture

The ES9027PRO used in the RS451 is a high-end 32-bit, 8-channel DAC chip designed with ESS’s HyperStream® architecture, ​delivering precise performance optimised for hi-fi audio applications. Its class leading specifications enabling delicate and clean sound reproduction. Supporting PCM up to 768kHz and DSD512, it ensures perfect compatibility with high-resolution audio formats.​ The variety of digital filters also offer a degree of sound customisation, to suit different styles of music or listening preferences. 

Advanced Headphone Architecture

By utilising two DAC chips within its advanced circuitry, the RS451 can deploy one chip for the traditional pre-out stage, and a separate one for the headphone output stage. In this way, the two signal paths are completely separated. The high-performance headphone stage further consists of four individually driven amplifiers that provide strong and stable output, even for low-impedance headphones. Further clarity and performance are guaranteed by the isolated power supply design for each channel. The result is a truly first-class headphone system, all in one box.  

Innovative Signal Processing

The RS451 makes use of Rose’s Digital Processing Core (DPC) Module, which was originally developed for the RD160 DAC and further employed in the RS151. This module precisely synchronizes any digital signal the DAC receives with a high-precision Femto clock as an I2S signal. It applies clock synchronization and locking processes to minimise jitter, allowing for accurate processing and a natural, clear sound performance. By isolating this module away from the wider CPU circuitry, it’s possible to eliminate signal distortion and interference that’s generated within the unit from the digital audio path. The result is accurately processed data, resulting in a natural and clean sound across a wide range of digital formats. 

ROSE OS

At the centre of the RS451 is ROSE OS, HiFi Rose’s Android-based operating system, which opens a world of music and video content to your streamer. ROSE OS supports local network music playback within Rose’s Music app, as well as CD playback and ripping via a connected optical drive. There is also support for internet radio, Spotify Connect, Tidal, Qobuz and Apple Music. The RS151 is also Roon Ready and Plays with Audirvāna certified. In addition, the operating system offers support for video playback, either locally or within the Tidal or Rose Tube apps. 

Above and Beyond

As well as ROSE OS, the RS451 makes use of the ROSE Audio Engine, an in-house development that ensures all digital audio is delivered to the DAC without loss for precise signal processing. 

The upgraded 8-Core CPU used in the RS451 boasts powerful data processing and improved graphics performance. The result of this upgrade is the best ROSE OS experience yet, including support for larger music libraries.

Connect what you need

The RS451 offers a well-organized rear panel layout with intuitive port placement, tailored for real usage scenarios. It includes only the essential input and output options for high-fidelity playback, arranged for both simplicity and connection stability. The spacing between ports is carefully considered to reduce interference between devices, making installation more convenient and flexible across various environments.  

With support for high-quality Bluetooth playback, USB playback, a hi-res coaxial input (supporting up to 32-bit / 384kHz PCM and DSD128), an optical input, HDMI eARC connection and a traditional RCA input, as well as balanced and unbalanced outputs – there’s very few systems the RS451 is not at home in.  

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