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The Leo

Our claim was high, with the Westend Audio Systems LEO we wanted to develop no more and no less than the best 300B-SE integrated amplifier of the modern era. We are proud of our new product and believe: It succeeded! And „best“ by no means refers only to the revolutionary tube circuit and the superior sound, but also to the housing and the equipment.

“With the Leo, the 300B for the first time opens up another world of speakers without losing the sound characteristics of the cult triode. The fascinatingly good-sounding integrated amplifier also impresses with state-of-the-art equipment and gentle tube management. We have never heard a better and – not surprisingly – more powerful single-ended 300B amp. In addition, the Leo offers all the features of a contemporary integrated amplifier and is also pretty as a picture. Big compliments!”

_Roland Kraft, stereoplay 11/2018

“LEO is a musical experience that flows forth in an unending 4-dimensional richness, completely devoid of artificialities and exaggerations, only pure musical content. With a good recording, the musical content (not the sound pressure) is even felt as a touch on the skin. Pure magic !”

_Nils Rigeblad, Professional Musician (Cellist) and owner of

The LEO is manufactured by its developer Günther Mania himself. The resonance-optimized housing is supplied by WESTEND AUDIO. As with the MONACO, it consists of milled aluminum parts whose surface allows many finishes: anodized, chrome-plated, gold-plated… And the equipment is also as you would expect from a modern amplifier – including a sophisticated Bluetooth and an excellent phono board. 

But at the heart of it are, of course, the two 300B power tubes that run in single-ended Class A operation in the LEO. Unusual is not only that the two 300B are installed horizontally (and so the usual old-fashioned tube amplifier look can be avoided), but a revolutionary circuit that comes instead of the usual 7-8 watts of a 300B smoothly to more than double and that with at least the same life! Because we know: Outputs of 7-8 watts are usually not enough to enjoy music without fear of clipping. But with 20 tube watts many loudspeakers can be operated perfectly. In short: The LEO is our interpretation of the modern 300B tube amplifier.

Technical Specifications

Output power 4 Ohm (THD): 5% 20 W
Output power 8 Ohm (THD): 5% 11 W
Frequency response 5V in 4 Ohm (-3 dB): <20 Hz–>35 kHz
Input impedance Cinch: 10 kOhm
Input impedance XLR: 20 kOhm (symmetrical)
Input impedance Phono MM: 47 kOhm // 100 pF
Input impedance Phono MC: 1 kOhm
Sensitivity Cinch: 30–300 mV (adjustable)
Sensitivity XLR: 30–300 mV (adjustable)
Sensitivity Phono MM: 300 μV–3 mV (adjustable)
Sensitivity Phono MC: 30 μV–300 μV (adjustable)
Signal-to-noise ratio high level (10 W/4 Ohm): 98 dB(A)
Signal-to-noise ratio Phono MM (10 W/4 Ohm): 84 dB(A)
Signal-to-noise ratio Phono MC (10 W/4 Ohm): 74 dB(A)

Bluetooth input
Bluetooth Standard: V4.2
Codecs: BC, MP3, AAC, Faststream, APTX
Samplerate (adaptive): bis 96 kHz/16 Bit
Frequency response: 20 Hz–20 kHz
Signal-to-noise ratio: 96 dB

Tubes: 2 × ECC81, 2 × 300B (matched)
Operating voltage: 230 V (internally switchable to 115 V)
Power consumption operation: 160 W, Standby < 0,5 W

Dimensions (W × × D): 430 × 430 × 135 mm (depth including the speaker terminals)
Weight: 14 kg (chrome & gold finish weights more)

Leo Westend Audio System Tube Amp Amplifier Röhrenverstärker Röhrenvollverstärker Hifi High-end High End München Munich