Mudlark A205, 20-watt per channel, Class A2 triode amplifier
Silicon Chip Publications Pty. Ltd; Brookvale NSW
- País
- Australia
- Fabricante / Marca
- Silicon Chip Publications Pty. Ltd; Brookvale NSW
- Año
- 2005
- Categoría
- Amplificador de audio o mezclador
- Radiomuseum.org ID
- 324357
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- Numero de valvulas
- 6
- Numero de transistores
- Hay semiconductores.
- Semiconductores
- Principio principal
- Amplificador de Audio; Hi-Fi-High End products
- Gama de ondas
- - no hay
- Tensión de funcionamiento
- Red: Corriente alterna (CA, Inglés = AC) / 240 Volt
- Altavoz
- - Este modelo usa altavoz exterior (1 o más).
- Material
- Metálico con lámparas a la vista.
- de Radiomuseum.org
- Modelo: Mudlark A205, 20-watt per channel, Class A2 triode amplifier - Silicon Chip Publications Pty.
- Forma
- Sobremesa, caja, normalmente con tapa (panel no inclinado).
- Anotaciones
-
The Mudlark A205 is a 3-stage lower-powered single-ended design using two paralleled triode-connected beam power pentodes. It also does not use a conventional output transformer but uses a choke as the combined plate load for the triodes, with the output signal being capacitively coupled to a 100 V transmission line transformer. Other novel features include positive drive (class A2) via an emitter follower to the grids of the output valves and quite a complex power supply which includes protection for the valves.
The A2 designation stands for class A2 operation. This refers to class-A which involves positive drive to the grids of the output valves on positive signal peaks for increased efficiency and higher power (sometimes called "extended" class-A in valve literature).
The circuit is unconventional because of the emitter follower used to drive the grids of the output valves and in the use of a choke as the plate load instead of a conventional output transformer.
The circuit is a “parafeed” configuration which uses a relatively low-cost high impedance choke as the load for the plates of the output valves and a capacitor to couple the audio signal to the primary of the output transformer. As a result, there is zero DC in the primary winding, so the output transformer can be much smaller and lower in cost without sacrificing quality.
It also incorporated a delayed B+ soft start circuit.
The Mudlark A205 comes in two parts, the main amplifier, and the separate transformer power supply box.
Designed by David Whitby and published as a kit in Silicon Chip, August & September 2005.
Specifications:
Output power: 20 watts per channel into 8Ω Input sensitivity: 360mV for 10W into 8Ω Signal-to-noise ratio: 67dB unweighted (22Hz to 22kHz); -91dB A-weighted, both with respect to 20W into 8 Ω.
Harmonic distortion: typically, <1.5% at listening levels. Frequency response: ±3dB, 12Hz-57kHz Damping factor: >6 with feedback, >2 without.
- Mencionado en
- -- Original prospect or advert (Silicon Chip, August & September 2005.)
- Autor
- Modelo creado por Gary Cowans. Ver en "Modificar Ficha" los participantes posteriores.
- Otros modelos
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Donde encontrará 2 modelos, 1 con imágenes y 2 con esquemas.
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