Viva Audio Viva Audio Solista 845 Power amp (MkIII) - Single Ended Triode 845

High-end integrated SET 845: point-to-point wiring, zero negative feedback, reference dynamics and timbre, capable of driving many real-world speakers with an ease rarely seen in a triode amplifier.

Technical Specifications:
* Topology: Single-Ended Triode (Class A), zero negative feedback.
* Tube Set (MkIII): 4× 845 (output/power), 2× 6SN7GT (driver),
* Rated Power: approx. 22 W/8 Ω (MkIII, recent publications). Some retailer spec sheets list 10–25 W depending on the version/test.
* Inputs/Ergonomics: 4 RCA line inputs + 1 “direct input”, solid palladium-plated copper speaker terminals,
* point-to-point wiring.
* Dimensions: 430 × 250 × 520 mm • Weight: 35 kg

Awards & Press Reviews (excerpts)
* Twittering Machines (01/2024): “Single-ended Class A 845, 22 W… point-to-point construction, no feedback.” Emphasizes authority and naturalness. Twittering Machines
* The Ear (01/2025): “22 W Class A power house”; high perceived power, great dynamics; notes on the importance of speaker selection for the final balance. The Ear
* StereoNET (03/2025): “The best of both worlds: speed/basic response close to a good solid-state amplifier, with the naturalness of a tube; fewer matching constraints compared to other tube amplifiers.” stereonet.com
* Various reviews/blogs: very low background noise for an 845, better-controlled bass than expected, strong resolution. Mimic-Audio+1

Sonic advantages (vs. other tube amps)
* It's a great match with my Cube Audio Nenuphar speakers, often also paired with Stenheim.
* Compared to the 300B/2A3 (low-power SET): the 845 offers more headroom, better bass control, and superior macro-contrast, while maintaining full timbres. (Corroborates tests highlighting the dynamics and speed of the Solista.) stereonet.com+1
* Compared to KT88/EL34 push-pull amps: less absolute "electric grip," but a more holographic image, more organic temporal coherence and texture; typical DHT harmonic grain. (Press summary.) stereonet.com
* Compared to OTLs: wider load/impedance compatibility thanks to output transformers, low background noise for its category. Mimic-Audio

Speaker pairings
* High efficiency / simple loads (92 dB+; simple crossovers): Tannoy, Devore, Zu, Klipsch Heritage, Audio Note, full-range drivers → superlative micro-dynamics and texture, lively sound at realistic levels with low wattage. (Press & forum feedback.) The Ear+1
* Medium sensitivity (88–91 dB): possible with a consistent impedance (e.g., Audiovector R6, successfully tested), a reasonably sized room, and careful cabling. chisto.com
* “Difficult” loads (sensitivity < 86 dB, complex impedance, electrostatics): not recommended or must be validated by listening test. (General principle, reinforced by press reviews on speaker/amplifier compatibility.) The Ear

Use
* Rapid warm-up; Class A operation (generates heat).

* Optimized for home rooms with realistic listening levels; recommend 90–92 dB+ speakers for full potential.

Condition / Contents
* Condition: Excellent - very dark blue color
* Tubes used less than 500 hours
* Accessories: Original packaging
* History: Second-hand, invoice available
* Audition possible in Lille - shipping available worldwide

Keywords
Viva Audio, Tekton, Solista 845, integrated amplifier, Class A, 845, 6SN7, 6C45, triodes, Audio Note, tektron audio