HOPKINS 91K4224C Pio Capacitors Close Audio Tube Amplifier .47 300V

( Brand: Hopkins ), ( Manufacturer Part Number: 91K4224C ), ( Part Type: Capacitor Tube Amplifier ), ( Country Of Origin: United Kingdom )

Review HOPKINS Vintage Pio Capacitors .47 300v Tested Close Match Uk Audio Tube Amp

The Hopkins 91K4224C PIO capacitors are a essential component for audio tube amplifiers operating at high voltages. These capacitors, specifically designed for close proximity to the audio tubes, are critical in providing the necessary filtering and coupling functions for the amplifier circuit.

The 91K4224C capacitors are rated for a working voltage of 300 volts, making them suitable for use in high voltage audio applications. The PIO (Plate-in-Oil) design ensures that the capacitor plates are submerged in an insulating oil, providing an additional layer of protection against electrical discharge and voltage spikes.

These capacitors are available in a capacitance value of 47 microfarads. The microfarad ( F) unit of measurement represents the capacitance level, which determines the amount of electrical charge a capacitor can store. In the context of audio amplifiers, capacitors are used to filter and smooth the output voltage, ensuring a consistent and stable power supply to the speakers.

The Hopkins 91K4224C capacitors are built to last, with a temperature range of -55 degrees Celsius to 105 degrees Celsius. This wide operating temperature range makes them suitable for use in various environments and conditions, ensuring reliable performance even in extreme temperatures.

Additionally, these capacitors feature a self-healing voltage rating, which means that they can recover from voltage spikes without sustaining damage. This is particularly important in audio tube amplifiers, where voltage fluctuations can occur due to the dynamic nature of the audio signal.

In summary, the Hopkins 91K4224C PIO capacitors are high voltage, high reliability components that are crucial for the proper functioning of close proximity audio tube amplifiers. With a capacitance value of 47 microfarads, a working voltage of 300 volts, and a wide operating temperature range, these capacitors offer excellent performance and durability for even the most demanding audio applications.

A Detailed Analysis of Hopkins 91K4224C PIO Capacitors for Audio Tube Amps

The Hopkins 91K4224C PIO capacitors are a popular choice for audio tube amplifier enthusiasts due to their high voltage rating and large capacitance value. In this analysis, we will explore the pros and cons of investing in these capacitors for your audio tube amplifier project.

1. High Voltage Rating: The 300V rating of these capacitors makes them suitable for use in high voltage audio tube amplifiers, ensuring the safe operation of the circuit.

2. Large Capacitance Value: With a capacitance value of 47 F, these capacitors provide sufficient energy storage for maintaining a consistent voltage, reducing voltage sag, and improving the overall sound quality of the amplifier.

3. Reliability: Hopkins capacitors are known for their long-lasting performance, making them a wise investment for those seeking a high-quality solution for their audio tube amplifier projects.

1. Cost: The Hopkins 91K4224C PIO capacitors are more expensive compared to other capacitor brands or lower voltage capacitors, which could be a significant deterrent for some enthusiasts.

2. Size: The large size of these capacitors may not be suitable for all audio tube amplifier projects where space is a constraint.

3. Availability: These capacitors may not be readily available at local electronics stores or online marketplaces, requiring specialized suppliers or importing from other countries, which could add to the overall cost and shipping time.

In conclusion, the Hopkins 91K4224C PIO capacitors offer several advantages, such as their high voltage rating, large capacitance value, and reliability. However, they also come with some disadvantages, including their cost, size, and availability. Ultimately, the decision to invest in these capacitors depends on your specific requirements, budget, and the priority you place on sound quality in your audio tube amplifier project.

If you are building a high voltage audio tube amplifier and prioritize excellent sound quality, the Hopkins 91K4224C PIO capacitors are a solid investment. However, if cost is a concern or if you have limited space, you may want to consider alternative capacitor brands or lower voltage capacitors. Always ensure you thoroughly research and compare different options to find the best fit for your project.

Details:

NOS vintage paper-in-oil capacitors tested for capacitance only.

part #: 91k4224c prices

• $16.00-$25.00

specifications vintacapacitor:

• brand: Hopkins
• mpn: 91k4224c
• part type: Capacitor Tube Amplifier
• country of origin: United Kingdom

offer vintacapacitor:

• started: March 3, 2026
• options: Ship-to-home
• availability: In Stock
• quantity: 1
• sold: 0

seller vintacapacitor:

• # reviews: 702
• rating: 100.0%
• city: Roanoke, Virginia

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• policy: No Returns

shipping vintacapacitor:

• cost: $7.29
• type: Calculated
• transit: 4-10 Days
• carrier: USPS
• service: USPS Ground Advantage
• class: Standard

general vintacapacitor:

• Vintage Audio Video > Vintage Parts Accessories > Vintage Capacitors
• condition: Open box

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