Experience the Acoustic Truth with the THÖRESS SE 845 Mono Power Amplifier, where pure Class-A single-ended design meets the iconic 845 power triode. This amplifier translates the intricate nuances of your music into a richly-textured sonic presentation, setting a new benchmark in high-fidelity audio reproduction.
The THÖRESS SE 845 Mono Power Amplifier exemplifies a meticulously engineered design that operates in single-ended Class-A mode utilizing the legendary 845 power triode. With an output power of up to 20 watts into various loudspeaker impedances (4, 8, or 16 ohms), the amplifier is built to handle the high-voltage swing required for optimal triode operation, approximately 300V peak-to-peak. The internal impedance of 2000 ohms presents a significant challenge for the output transformer (OPT) design. Thus, we developed a high-performance driver stage using dual EL822/CV2382 tubes in triode mode, providing robust driving capabilities while ensuring linearity and minimal distortion. The custom OPT maximizes the amplifier’s sonic potential, employing a dual-coil winding on a proprietary C-core that minimizes distortion and enhances frequency response. Complemented by low-noise operational characteristics achieved through thoughtful circuit design and construction techniques, the SE 845 amplifier delivers a truly dynamic listening experience.
Key Features
-
Single-Ended Class-A Operation: Operates using the 845 triode in a zero-feedback configuration, maximizing harmonic integrity and producing natural sound reproduction.
-
Custom Output Transformer: Designed in-house, the OPT features a dual-coil winding on an exceptionally large C-core, providing low distortion and superior frequency response across the audio spectrum.
-
Low Noise Operation: DC heating of the 845 triodes and precise filament balancing eliminate hum, ensuring crystal-clear audio even with highly efficient loudspeakers.
-
Adjustable Cathode Point Balance: Allows for optimization of signal current distribution across the filament for enhanced noise reduction.
-
In-House Mains Transformer: Customized for various voltage specifications, it reduces body noise emission and eliminates transformer vibrations from affecting the audio circuit.
Technical Specifications
- Output Power: 2x20 watts
- Tube Type: 845 power triode
- Operating Mode: Single-ended Class-A
- Input Sensitivity: Low
- Input Impedance: N/A
- Output Impedance: 4, 8, or 16 ohms
- Internal Impedance: 2000 ohms
- Mains Voltage Options: 100Vac, 120Vac, 220Vac, 230Vac, 240Vac, 245Vac
- Hum Cancellation: DC heating with potentiometer adjustment
