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S400 II

Name: Vacuum Tube Logic (VTL) S400 II
Brand: Vacuum Tube Logic (VTL)

Vacuum Tube Logic (VTL)

S-400 Series2004 – Present

AmplifiersPower AmplifiersTube AmplifiersDiscontinued

Estimated price (community-sourced)

$2,995

About the S400 II

The VTL S-400 II is a reference stereo tube power amplifier from Vacuum Tube Logic, introduced as a Series II redesign of the original S-400. It uses a fully balanced differential architecture, zero global negative feedback, auto-bias with fault sensing, and a user-adjustable damping factor control to tailor amplifier output impedance and loudspeaker matching. It is rated at 300 watts per channel in tetrode mode or 150 watts per channel in triode mode, and was described in review coverage as a high-end stereo amplifier priced at $33,500.

Specifications

Key Specifications

Impedance: 5Ω

Power: 300W

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