AI-generated product photo — not official manufacturer imagery.
Estimated price (community-sourced)
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
Full structured specifications are available to members.
Sign up to see full specificationsSee the full picture as a member
Create a free account to see where to buy, full structured specifications, similar components, and the systems that pair this with other gear.
Sign up free