Atoll Electronique PH200 Phono Preamplifier

Overview

The phono preamplifier PH200 has two low-noise toroidal transformers, one per channel. A steel shell electrically connected to the chassis fully shields the power supplies to avoid parasitic radiation. This shell, as well as the filter capacitors and the chassis, are treated against mechanical vibrations using a specifically adapted material. Operating consumption remains less than 2W. The printed circuit board has a chemical gold nickel finish, which optimises signal transfer. The masses are routed in a star pattern to ensure perfect power supply noise rejection.

• 8 mm brushed aluminium front panel.
• Silver mica technology RIAA filter capacitors.
• 2 very low noise linear transformers 3,5 VA each.
• 4 regulated power supplies.
• Total of capacitors: 54 400 µF.
• Input impedance: 47 kΩ.
• Input capacity: Nothing / 100 pF / 220 pF / 320 pF(*).
• MM gain: 40 dB (*).
• High-level MC gain: 47 dB (*).
• Low-level MC gain: 60 dB (*).
• Signal/Noise ratio at 1 kHz: 80 dB.
• Crosstalk at 1 kHz: < -86 dB.
• Frequency response (20 Hz – 20 kHz): < 0,1 dB.
• THD: 0,05%.

Connectivity

• Ground
• 1 Module signal output.
• 1 Turntable signal input.
• Settings block (Left channel).
• Settings block (Right channel).
• 1 12V Trigger Input.

Filtering is carried out by eight 6800 µF low series resistance capacitors made to specifications. The RIAA filter capacitors are silver mica technology, which offers highly natural restitution of timbres.

The audio stages, made entirely of discrete components, have low feedback rates and are polarised in class A. These stages are perfectly separated (full double mono) up to the RCA output plugs. These are high quality directly and independently soldered onto the printed circuit in order to optimize signal transfer.

Each stage has two precise settings for quiescent current and offset. These stages operate on direct current, without a connecting capacitor, significantly improving the musicality.

The circuit developed specifically for the PH200 allows it to automatically adapt to any cell impedance value and, therefore, avoid any adjustment of this type.