MULLARD K166 Quad

( Brand: Mullard ), ( Manufacturer Part Number: K166 ), ( Model: MULLARD K166 ), ( Country Of Origin: United Kingdom )

Review MULLARD Kt Quad

Mullard K166 KT Quad - A Vintage Treasure for Audiophiles

The Mullard K166 KT Quad is a vintage quadruple triode audio valve, a remarkable piece of audio history that continues to captivate audiophiles worldwide. This valve, manufactured by Mullard, a renowned British electronics company, is a testament to the golden era of audio technology.

The Mullard K166 KT Quad is a high mu ( ) valve, known for its superior amplification capabilities. Each valve in the quad has a screen grid, which helps to reduce the internal noise, ensuring a cleaner and more precise sound. The valve is designed to operate at a plate voltage of 300V, making it suitable for use in high-end audio equipment.

The Mullard K166 KT Quad is not just a valve; it's an experience. It offers a warm, rich, and detailed sound that is unique to vacuum tube technology. The valve's tone is smooth, with a natural and unprocessed quality that modern solid-state amplifiers often struggle to replicate.

With a power rating of 3 Watts per channel, the Mullard K166 KT Quad is ideal for use in high-fidelity audio systems, particularly in applications where the subtle nuances of music are to be appreciated. Its distinctive glass envelope, adorned with the iconic Mullard logo, adds a touch of vintage charm to any audio setup.

In conclusion, the Mullard K166 KT Quad is more than just a valve; it's a symbol of audio heritage. Its performance, combined with its aesthetics, makes it a desirable component for any serious audiophile seeking a unique and authentic sound experience. Whether you're restoring a vintage hi-fi system or building a new one, the Mullard K166 KT Quad is a treasure worth considering.

Mullard K166 KT Quad Tubes: A Detailed Analysis

1. High Quality: Mullard is a well-known brand for producing high-quality vacuum tubes. The K166 KT Quad tube is no exception. It offers excellent sound quality, with a warm and rich tone that is highly valued in audio applications.

2. Durability: These tubes are known for their longevity, ensuring that they can withstand regular use over a long period.

3. Improved Bass Response: The Mullard K166 KT Quad tube is particularly good at enhancing the bass response, making it an excellent choice for those who value a strong, defined bass in their audio system.

1. Cost: Compared to some modern solid-state components, vacuum tubes can be quite expensive. The Mullard K166 KT Quad tube is no exception, and its cost may be a deterrent for some.

2. Maintenance: Vacuum tubes require regular maintenance, including replacing the filament and aligning the grid, which can be time-consuming and potentially costly.

3. Power Consumption: Vacuum tubes generally consume more power than their solid-state counterparts, which can lead to increased energy bills.

The Mullard K166 KT Quad tube is a high-quality vacuum tube that offers excellent sound quality, particularly in enhancing the bass response. However, its cost, maintenance requirements, and power consumption may be drawbacks for some.

If you are an audiophile who values warm, rich sound quality and a strong bass response, and you are willing to invest in quality equipment and accept the maintenance requirements of vacuum tubes, then the Mullard K166 KT Quad tube could be a worthwhile addition to your audio system. However, if you are looking for a more cost-effective, low-maintenance solution, you may want to consider a solid-state alternative.

Details:

4 kt66 all test good on my tester about same reading 85 no shorts from project that never got off the ground.

part #: k166 prices

• $59.00-$139.50

specifications tubesocketvintagego:

• brand: Mullard
• mpn: K166
• model: Mullard K166
• country of origin: United Kingdom

offer tubesocketvintagego:

• best offers: True
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• quantity: 1
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• started: January 14, 2026
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• Vintage Audio Video > Vintage Parts Accessories > Vintage Tubes Tube Sockets
• condition: Used

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• # reviews: 1849
• city: Seaford, New York

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