SIA-025
An integrated amplifier from Vitus Audio's Signature Series that switches between Class A and Class AB, now made as the SIA-025 Mk.II.
- Made by
- Vitus Audio
Pictures © Vitus Audio, from vitusaudio.com.
Why it is renowned
The SIA-025 has a long run of press awards: The Absolute Sound named it a Product of the Year in 2011 and 2013 and has given it its Editors' Choice award repeatedly, most recently for 2024, 2025 and 2026.12 Enjoy the Music reviewed the Mk.II in 2026 and called it a masterful and musically satisfying amplifier.3
The story
Vitus Audio designed the SIA-025 in 2010 from what it had learned on the SM-010 amplifier, using newly bought SolidWorks software to fit the whole circuit into the chassis it shared with the SS-010, SM-010 and SS-050. It was the company's first true integrated amplifier, launched about six months before the RI-100.1
It gives 25 watts a channel into 8 ohms in pure Class A or 150 watts in Class AB, switched from the remote.3 The Mk.II puts fully integrated circuits in the chassis of the SS-010 without adding size or noise, and follows the company's rule that no part works at more than a quarter of what it can handle.2 It has five balanced and unbalanced inputs, a preamplifier output for bi-amping, balanced speaker outputs and a bypass for a surround processor, and comes in white, black or silver.2
Sources
- History, Vitus Audio. vitusaudio.com, read 1 October 2026.
- SIA-025 Mk.II, Vitus Audio. vitusaudio.com, read 1 October 2026.
- Vitus Audio SIA-025 Mk.II review, Enjoy the Music. enjoythemusic.com, read 1 October 2026.
Last checked 2 October 2026, against the maker's own pages.