MastersounD EVO 300B
Tube amplifiers
€ 10990
MastersounD EVO 300B – four 300B valves in a parallel single-ended Class A integrated amplifier
The natural step up from the Compact 300B
The MastersounD EVO 300B uses four 300B output valves, with two valves per channel in a parallel single-ended circuit. As a result, output rises to 2× 21 W of pure Class A with zero negative feedback.
Because the topology remains single-ended throughout, directness, tonal flow and the absence of crossover distortion are preserved. Moreover, every unit is hand-built at MastersounD's factory in Arcugnano, Vicenza.
Parallel single-ended — more power without compromise
In a parallel single-ended circuit, two valves per channel share the same signal path. Therefore, output power increases without switching to push-pull operation.
Furthermore, MastersounD’s hand-wound output transformers are designed specifically for this four-valve configuration. As a consequence, energy transfer remains stable across the full audio band.
Connectivity and automatic bias
Inputs include one balanced XLR line input, one direct XLR input, three RCA line inputs and one direct RCA input. In addition, the direct inputs bypass the preamplifier stage.
Therefore, the EVO 300B can also be driven by an external preamplifier. Meanwhile, automatic bias keeps all four 300B valves at their ideal operating point. Consequently, no manual adjustment is required during normal use.
Italian craftsmanship
Above all, every EVO 300B is individually assembled, run in and checked before leaving the factory. The chassis combines steel with elegant Italian walnut veneer.
Those seeking even more output can step up to the MastersounD Evolution 845, which delivers 2× 55 W with four 845 valves.
Specifications
- Type: parallel single-ended Class A integrated amplifier
- Output power: 2× 21 W Class A
- Valves: 4× 300B, 2× ECC802, 2× 6SN7
- Inputs XLR: 1× line + 1× direct
- Inputs RCA: 3× line + 1× direct
- Input impedance: 50 kΩ
- Load impedance: 4–8 ohm
- Negative feedback: 0 dB
- Output transformer: bespoke MastersounD, hand-wound
- Bias: automatic
- Remote control: included
- Power consumption: 230 W
- Dimensions: 450×430×270 mm
- Weight: 34 kg
- Origin: hand-built in Italy
Frequently asked questions about the MastersounD EVO 300B
What is the difference between the EVO 300B and the Compact 300B?
The EVO uses four 300B valves per stereo pair, raising output from 2× 15 W to 2× 21 W. Both models share zero negative feedback and the same pure 300B philosophy. Therefore, the EVO suits a wider range of loudspeakers.
What is parallel single-ended and why does it matter?
Two valves per channel share the same single-ended signal path. Because the circuit never switches between waveform halves, crossover distortion is eliminated. In addition, output power rises without the trade-offs of push-pull designs.
Which loudspeakers suit the EVO 300B?
Loudspeakers of 88 dB sensitivity or above work best. Since output exceeds that of the Compact 300B, the EVO 300B suits a broader range of designs in medium-sized rooms.
Hear the MastersounD EVO 300B at Novus Audio
The MastersounD EVO 300B is available for a personal listening session at Novus Audio in the Netherlands. We welcome visitors by appointment, so you can hear what it does for your system.
