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Fosi Audio
Fosi Audio Box X4
~$79
Estimated price · may vary by retailer
The successor to the popular Box X2, adding Bluetooth connectivity and Bass/Treble tone controls to the phono stage. It serves as a bridge between vintage turntables and modern active speakers or headphones.
Specifications
TubesJan5654W × 2
TopologyPhono Preamp (MM) + Tube Buffer
InputsPhono (MM), Bluetooth 5.0
OutputsRCA, 3.5mm Headphone
FeaturesBass/Treble Controls, Ground Post
Things to Know
- ⚠Headphone output is relatively weak and can sound thin with high-impedance headphones.
- ⚠Tube sockets are extremely tight; changing tubes requires significant force and care.
- ⚠Bluetooth input is 'always on' and can be hijacked by neighbors if not paired.
Reviews
“The mids and highs have been brought forward with a more warmer sound, larger presence, lows more subdued and nuanced... vocals are, just wow.”
— AudioScienceReview (AddamR)
“Got the Fosi phono preamp so I could run my Technics 1100... Huge bang for your buck with this little unit.”
— Reddit r/BudgetAudiophile (Haiiryyone)
Video Review
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