K40P-2b Paper-in-Oil Capacitors

K40P-2b capacitors are a type of vintage audio capacitor that was manufactured in the former Soviet Union, in Ukraine, during the 1960's-1990's. These capacitors are known for their use in various audio equipment, including amplifiers, radios, and other electronic devices. They have gained a reputation among audiophiles and vintage audio enthusiasts for their unique characteristics and sonic qualities.

Here are some key features and details about K40P-2b capacitors:

Paper-in-Oil Design: K40P-2b capacitors are constructed using a paper-in-oil (PIO) design. This means that the capacitor's dielectric material is typically paper, and it is impregnated with oil to improve its performance and longevity. The use of oil helps to reduce heat generation and maintain stable capacitance values over time. Capacitor plates are made of aluminium foil.

Vintage Aesthetics: K40P-2b capacitors are recognized for their distinctive appearance, often featuring a cylindrical metal can without or with colored paint and markings that indicate their capacitance and voltage rating. The colored paint on the capacitors can vary, with common colors being pink, orange, and grey.

Capacitance Values: These capacitors typically come in a range of capacitance values, in the range from 1000 picofarads (pF) to 0.047 microfarad (uF). The exact capacitance value is usually indicated by markings on the capacitor's body.

Voltage Rating: K40Y-9 capacitors have voltage ratings 400 volts.

Audio Applications: Audiophiles and vintage audio enthusiasts often seek out K40P-2b capacitors for use in audio equipment, especially in vintage tube amplifiers and other audio gear. They are believed by some to impart a warm and vintage sound character to the audio signal.