All-in-One Tube DAC, Headphone Amplifier & HiFi Preamplifier

The Fosi Audio GR40 Tube DAC Headphone Amp Preamp is a multifunctional desktop HiFi audio solution that combines a premium DAC, vacuum tube preamplifier, Bluetooth receiver, and headphone amplifier into one compact and elegant unit.

Built for audiophiles, desktop music enthusiasts, and home audio users, the GR40 delivers warm analog-style sound with modern high-resolution digital decoding. Featuring the ESS9028Q2M DAC chipset, Bluetooth aptX HD/LL support, USB 32bit/384kHz decoding, and bass/treble controls, the GR40 creates a rich, smooth, and immersive listening experience for both headphones and active speakers.

Perfect for music streaming, desktop HiFi systems, gaming, movies, and wireless audio playback.

Premium ESS9028Q2M DAC for High-Resolution Audio

At the core of the GR40 is the highly respected ESS9028Q2M DAC chipset engineered for detailed, low-noise, high-resolution audio playback.

Hi-Res Audio Support:

• PCM up to 32bit / 384kHz
• Native DSD256 playback
• Advanced digital audio decoding
• Low-noise signal processing
• Enhanced dynamic range

This premium DAC architecture delivers:

• Clear vocals
• Deep controlled bass
• Smooth treble extension
• Wide soundstage
• Accurate detail retrieval

Ideal for:

• HiFi music streaming
• Lossless audio playback
• Desktop audiophile systems
• Studio-quality listening

Warm Tube Preamplifier Sound

The GR40 combines modern DAC technology with tube-style analog warmth for a more natural and musical listening experience.

Tube Audio Characteristics:

• Smooth analog tonality
• Warm vocal presentation
• Rich musical texture
• Relaxed listening experience
• Enhanced midrange presence

The preamp stage preserves:

• Natural instrument timbre
• Vocal richness
• Musical depth
• Organic sound presentation

Perfect for:

• Vocal music
• Jazz
• Acoustic recordings
• Long listening sessions
• Analog-inspired HiFi setups

Bluetooth aptX HD & aptX Low Latency Support

The GR40 features the Qualcomm QCC3031 Bluetooth chipset for high-quality wireless streaming with low latency performance.

Supported Bluetooth Codecs:

• aptX
• aptX HD
• aptX Low Latency (LL)

Wireless Audio Benefits:

• Improved wireless sound quality
• Reduced latency for movies and gaming
• Stable Bluetooth connection
• Detailed audio transmission
• Convenient smartphone streaming

Perfect for:

• Wireless music playback
• TV and movie audio
• Mobile device streaming
• Casual desktop listening

Versatile Desktop Audio Connectivity

The GR40 supports multiple input sources and output configurations, making it a flexible desktop audio hub.

Inputs:

• Bluetooth
• USB
• Optical
• Coaxial

Outputs:

• RCA Output for Active Speakers
• 3.5mm Headphone Output

The GR40 easily integrates with:

• Powered speakers
• Desktop audio systems
• Headphones
• Gaming setups
• PCs and laptops
• TVs and streamers

Dedicated Headphone Priority Mode

The GR40 includes an intelligent headphone priority mode for seamless desktop use.

Headphone Features:

• Automatic headphone priority switching
• Convenient private listening
• Clean headphone amplification
• Easy transition between speakers and headphones

Perfect for:

• Desktop workstations
• Late-night listening
• Shared environments
• Compact HiFi setups

Compact Desktop-Friendly Design

Despite its multifunctional capabilities, the GR40 maintains a compact and elegant desktop footprint.

Design Features:

• Compact stereo preamp design
• Intuitive control layout
• Minimal desktop footprint
• Elegant tube-inspired styling
• Easy-access front controls

Ideal for:

• Desktop HiFi systems
• Home office audio
• Small audio setups
• Modern workspaces

Analog Sound Controls for Personalized Audio

The GR40 features physical tone controls for adjusting sound characteristics in real time.

Front Panel Controls:

• Master volume control
• Bass adjustment
• Treble adjustment
• Input selection
• Bluetooth reset control

Users can fine-tune:

• Bass impact
• Vocal warmth
• Treble brightness
• Overall tonal balance

This flexibility allows better matching with:

• Different headphones
• Active speakers
• Music genres
• Listening preferences

Plug-and-Play Convenience

The GR40 is designed for simple operation without requiring complicated software installation.

User-Friendly Features:

• Driver-free operation
• Plug-and-play USB DAC
• Easy Bluetooth pairing
• Quick input switching
• Seamless desktop integration

Perfect for users seeking premium sound without complex setup procedures.

Technical Specifications

• Product Type: Tube DAC Headphone Amplifier & Preamplifier
• DAC Chipset: ESS9028Q2M
• Bluetooth Chipset: Qualcomm QCC3031
• Supported Bluetooth Codecs:
  • aptX
  • aptX HD
  • aptX Low Latency
• USB Audio Support:
  • PCM up to 32bit / 384kHz
  • Native DSD256
• Inputs:
  • Bluetooth
  • USB
  • Optical
  • Coaxial
• Outputs:
  • RCA Output
  • 3.5mm Headphone Output
• Features:
  • Headphone priority mode
  • Bass & treble controls
  • Plug-and-play operation

Features

• ESS9028Q2M HiFi DAC chipset
• Tube DAC preamplifier design
• Bluetooth aptX HD & LL support
• USB 32bit/384kHz decoding
• Native DSD256 playback
• RCA and headphone outputs
• Warm analog-style sound
• Bass & treble controls
• Compact desktop audio solution
• Plug-and-play operation