Fosi Audio GR70 Tube Headphone Amplifier & Preamplifier
Key Features
Pure Tube Amplification
Adjustable Impedance and bass & treble Control
2-in-1 Headphone Amp and Preamp
Supports 16–300Ω Headphone Impedance
Product Description
GR70 Vacuum Tube Headphone Amp
Featuring two replaceable 5654W and two 6Ж4/6Ж8 vacuum tubes, it offers a customizable auditory experience. Immerse yourself in the authentic warmth and smoothness of analog audio.
Integrating Vintage Charm with Modern Precision
The GR70 is a two-in-one headphone amp and preamp. Easily integrate this tube preamp into your home audio system with its multiple headphone jacks and RCA input/output options.
- Input: RCA; Output: RCA, 6.35mm/3.5mm Headphone Output;
- Rated Power Output: 90mW@32Ω; Max Power Output: 300mW@32Ω; Power Input: DC 12V/3A;
- Headphone Impedance: Low Mode: 16Ω-120Ω, High Mode: 120Ω-300Ω;
Pure Tube-Amplification: The GR70 headphone tube amp combines vintage charm with modern tech, delivering authentic tube essence. Perfect for headphone enthusiasts, it pairs excellently with over-ear and in-ear headphones for superior audio
Quad Tubes: Features two 5654W and two 6Ж4/6Ж8 vacuum tubes for two-stage amplification. The 5654W tubes boost voltage, while the 6Ж4/6Ж8 tubes handle power amplification. This setup delivers balanced, transparent, and textured sound
User-Friendly Design: This tube headphone amp preamplifier offers intuitive controls, including a large volume knob, dual-side ventilation holes, bass & treble controls, high and low impedance mode switching, making it versatile enough
Two-in-One: It supports low and high impedance modes switching to adapt 16Ω-300Ω headphones, and features 6.35mm/3.5mm headphone jacks on the front and RCA Input/Output on the rear for home audio HiFi system integration
Compact Yet Powerful: Crafted with a CNC-machined aluminum alloy body, the GR70 is both durable and refined. Despite its compact size, it delivers up to 300mW power output and 1.2V RCA output with SNR ≥97dB—offering warm, clean, and dynamic sound
Specifications
|
Brand |
Fosi Audio |
|
Model |
GR70 |
|
Product Type |
Tube Headphone Amplifier & Preamplifier |
|
Amplification Type |
Class-A Tube Amplification |
|
Vacuum Tubes |
2 × 5654W + 2 × 6Ж4/6Ж8 |
|
Input |
RCA Stereo |
|
Outputs |
RCA Stereo, 6.35 mm Headphone, 3.5 mm Headphone |
|
Rated Output Power |
90 mW @ 32 Ω |
|
Maximum Output Power |
300 mW @ 32 Ω |
|
Headphone Impedance |
16–300 Ω |
|
Low-Impedance Mode |
16–120 Ω |
|
High-Impedance Mode |
120–300 Ω |
|
RCA Output Level |
1.2 V |
|
Frequency Response |
20 Hz–20 kHz (±1 dB) |
|
Signal-to-Noise Ratio (SNR) |
≥97 dB |
|
Dynamic Range |
≥97 dB |
|
THD+N – Headphone Output |
≤0.5% |
|
THD+N – RCA Output |
≤0.26% |
|
Tone Controls |
Adjustable Bass and Treble |
|
Volume Control |
Rotary Volume Knob |
|
Power Input |
DC 12 V / 3 A |
|
Chassis Material |
CNC-Machined Aluminium Alloy |
|
Colour |
Black |
|
Dimensions (W × H × D) |
192 × 46 × 129 mm |
|
Weight |
Approximately 0.9 kg |