The Sophia Electric 91‑01 300B are power monoblocks in a pure single-ended configuration on the legendary 300B triode — with no global negative feedback. They deliver 9 W per channel with the sound the best 300B designs are famous for: tangible, fluid and full of colour, with a magical midrange.
Each monoblock is based on a simple, audiophile circuit: a 6SN7 input valve, a 300B output valve and a 5Z3PA valve rectifier. A high input impedance (200 kΩ) and 4 and 8 Ω speaker taps make system matching easy. The design is intended for efficient loudspeakers.
The absence of negative feedback, low distortion (0.18% at 1 kHz) and a wide bandwidth (12 Hz – 35 kHz) are a recipe for clean, direct and emotional sound. A choice for the audiophile who values the classic 300B sound in an uncompromising execution.
| Output power | 9 W per channel (8 Ω, 1 kHz) |
| Valves | 1× 300B (output), 1× 6SN7 (input), 1× 5Z3PA (rectifier) |
| Configuration | single-ended, no negative feedback |
| Input impedance | 200 kΩ |
| Input sensitivity | 500 mV (full power) |
| THD distortion | 0.18% (1 kHz) |
| Frequency response | 12 Hz – 35 kHz (±3 dB) |
| Speaker taps | 4 and 8 Ω |
| Dimensions (W × H × D) | 325 × 185 × 245 mm |
| Weight | 15.9 kg (each) |
Single-ended valve monoblocks on the 300B triode — 9 W per channel, no negative feedback, valve rectifier. Tangible, fluid sound with a magical midrange.
