Fosi Audio GR70 features:

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 6AC7 vacuum tubes for two-stage amplification. The 5654W tubes boost voltage, while the 6AC7 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.

What's in the box:
Fosi Audio GR70
6AC7 Vacuum Tubes
5654 Vacuum Tubes
Tube Protection Covers
12V/3A Power Supply