MULLARD MT-177 Audio Pentode Tube British Brimar EF37A Mullard/brimar

( Brand: Mullard ), ( Manufacturer Part Number: MT-177 ), ( Part Type: Tube )

Review MULLARD Vintage Audio Pentode Tube British Mullard/brimar Style

Mullard MT-177 EF37A Audio Pentode Tube - A British Gem from Mullard/Brimar

Step back in time with the Mullard MT-177 EF37A Audio Pentode Tube, a classic British component that embodies the rich heritage of Mullard and Brimar. This tube, a testament to the golden age of audio technology, is a must-have for any vintage or modern audio system enthusiast.

The Mullard MT-177, a direct descendant of the renowned EF86, boasts a versatile design suitable for a wide range of applications. As an audio pentode tube, it excels in amplifier stages, delivering a rich, warm, and detailed sound that is the hallmark of tubes. Its EF37A designation signifies its equivalency with the EF86, making it a perfect substitute for those seeking a slightly different tonal character.

Crafted by Mullard, a brand synonymous with quality and reliability, the MT-177 is built to last. The tube's sturdy construction, combined with its robust heater filament, ensures a long life even under heavy usage. The Mullard MT-177 EF37A Audio Pentode Tube is also a product of Brimar, a sister company known for its precision and adherence to high standards.

In terms of performance, the Mullard MT-177 offers a high plate current capability, ensuring it can drive even the most power-hungry speakers with ease. Its rich harmonics and warm, smooth sound make it an excellent choice for a variety of uses, from guitar amplifiers to hi-fi systems.

Whether you're restoring a vintage radio, building a custom guitar amp, or upgrading your hi-fi system, the Mullard MT-177 EF37A Audio Pentode Tube is a valuable addition. Its unique character, combined with its versatility and reliability, make it a standout choice among audio enthusiasts. Experience the warmth, richness, and detail that only a tube like the Mullard MT-177 can deliver.

The Mullard MT-177 EF37A audio pentode tube, manufactured by Mullard (a Marconi brand) or Brimar, is a popular choice among audiophiles for its high-quality sound output. Here are some pros and cons to consider before making a purchase:

1. High-quality sound: Known for delivering rich, warm, and detailed sound as compared to other tubes in its class.

2. Durability: Mullard and Brimar tubes are generally well-built and can last longer than cheaper alternatives.

3. Brand reputation: Mullard and Brimar are reputable brands with a long history in the audio industry.

4. Versatility: This tube can be used in various applications, such as audio amplifiers, radio, and even some television sets.

1. Price: Mullard and Brimar tubes tend to be more expensive than other brands due to their high-quality construction and reputation.

2. Availability: These tubes may be harder to find in local stores, and replacements can be costly if they burn out.

3. Sensitivity: As with any vacuum tube, the MT-177 EF37A can be sensitive to poor quality power supplies and can require careful setup and maintenance.

In conclusion, the Mullard MT-177 EF37A audio pentode tube offers excellent sound quality, durability, and versatility. However, its higher price point and potential difficulty in finding replacements should be carefully considered. If you're an audiophile looking for a high-quality tube to improve your audio setup, this might be a worthwhile investment. On the other hand, if you're on a tight budget or prefer a more readily available option, you might want to explore other brands first. Ultimately, the choice depends on your personal audio preferences and budget.

Details:

Factory red coating mostly worn off. Glass envelope intact. The EF37A is prized for its smooth gain characteristics and historical use in vintage British electronics. Pins show light oxidation from long-term storage.

This one appears to be a vintage EF37A, well-known British audio pentode used in classic microphones, early studio equipment, and high-end amplifiers. Internal elements appear stable with no loose pieces. Untested estate tube. The original red coating and factory print have worn off over time, which is common for these tubes, but the internal structure remaining markings clearly match EF37A family.

Review all photos. Sold exactly as found. Some lettering still faintly visible EF37. A great piece for collectors, restorers, and audio hobbyists who appreciate classic European small-signal tubes.

Please review photos closely. The original owner stored every tube carefully in doors and organized them by type purpose.

part #: mt177 prices

• $100.00-$119.95

specifications tubesocketvintagego:

• brand: Mullard
• mpn: Mt-177
• part type: Tube

seller tubesocketvintagego:

• # reviews: 153
• city: Carthage, Missouri
• rating: 100.0%

offer tubesocketvintagego:

• options: Ship-to-home
• started: November 26, 2025
• best offers: True
• quantity: 1
• sold: 0
• availability: In Stock

general tubesocketvintagego:

• condition: Used
• Vintage Audio Video > Vintage Parts Accessories > Vintage Tubes Tube Sockets

shipping tubesocketvintagego:

• class: Standard
• service: USPS Ground Advantage
• transit: 6-12 Days
• type: Calculated
• cost: $5.09
• carrier: USPS

payments tubesocketvintagego:

• credit card: Discover
• wallet: Google-pay
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• policy: No Returns

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