Интегральные усилители — Fezz Audio Fezz Mira Ceti 300B

The Mira Ceti 300B is a stereo single-ended triode integrated amplifier made in Poland by Fezz Audio, a spin-off of Toroidy, a maker of toroidal transformers established in 1991. Fezz describes it as one of the few single-ended valve amplifiers anywhere built with toroidal output transformers. The current Evolution version sells for USD 5,495 or GBP 4,495.

Key specs that matter

One 300B directly heated triode per channel, supplied by Psvane, forms the class A single-ended output stage, with a 6SN7-family double triode (6N8S or 6SN7EH) working as input and driver valve. Maximum output is 2 x 8 W, with separate speaker taps for 4 and 8 ohm loads. Fezz quotes total harmonic distortion below 0.4 percent and a frequency response of 20 Hz to 45 kHz at the -3 dB points. Connections include three RCA line inputs plus an output for a powered sub. Power draw is 115 W, and the mains input is protected by a 3.15 A slow-blow fuse. The chassis measures 420 x 380 x 200 mm and weighs 19.5 kg. Finish options are Black Ice, Sunlight, Big Calm, Burning Red, Evergreen and Moonlight, with others by special order.

Engineering and use context

For the output transformers Fezz uses toroidal cores wound from strips of cold-rolled, grain-oriented silicon steel, which offer high flux density and have almost no air gap. The circuit applies only about 3 dB of negative feedback. The case styling comes from the design studio Kabo & Pydo. Bias for the 300B pair is set automatically, which means replacement valves do not need manual adjustment with a meter. The third input can also receive Bluetooth audio. Volume and input selection sit on the front panel and are duplicated on a supplied remote handset, and a metal cage with a clear front is included to protect the valves from accidental contact. The warranty runs for two years and excludes valves.

Pairing

With so little power available, loudspeakers of high sensitivity and an easy impedance curve are the natural match, and a modest room of about 20 m2 keeps the demand on those few watts within reach. Owners of smaller, less sensitive speakers can use the sub output to hand the lowest octaves to a powered subwoofer. The output taps should be matched to the nominal impedance of the chosen speakers.

Alternatives

The Fezz Luna EVO is a push-pull integrated with four EL34 valves giving 40 W per channel in ultra-linear mode or 20 W in triode mode.