![\"4-Tungsram-EF86-Vintage-Audio-Vacuum-Tubes.jpg\"](\"https:\/\/busther.com.co\/wp-content\/uploads\/2026\/01\/EF86-TUNGSRAM-QUAD-2-300x300.jpg\")
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Introduction: The Classic European Sound
Elevate the performance of your audio project with this exceptional set of 4 Tungsram EF86 Vacuum Tubes. Manufactured during the golden age of European electronics in Hungary, these pentodes are highly regarded among audiophiles for their robust construction, superior internal shielding, and, above all, their ultra-low noise characteristics and reduced microphonics. They are a preferred choice for high-gain preamplifier input stages, delivering the clarity, reliability, and authentic vintage tone sought after by audio enthusiasts and restoration specialists.<\/p>\n
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Testing & Reliability
We understand that reliability is essential when it comes to vintage electronic components. That is why these 4 Tungsram EF86 Vacuum Tubes have been professionally tested for emission and internal shorts using a vintage Kyoritsu Tube Tester, with all units passing successfully and confirmed to be fully operational. Although they originate from different production batches (factory codes shown below), their electrical performance makes them fully suitable for use together in the same audio equipment.<\/p>\n
Applications & Uses of the Set of 4 Tungsram EF86 Vacuum Tubes
The EF86 (equivalent to the 6267 and Z729) is a low-noise small-signal audio pentode specifically designed for high-fidelity audio applications. This set is ideal for:<\/p>\n
Guitar Amplifiers: Ideal for restoring the Normal channel of vintage Vox AC30, Matchless DC-30, and Dr. Z amplifiers, delivering the classic low-noise, harmonically rich tone these legendary designs are known for.<\/p>\n<\/li>\n
Classic Hi-Fi Audio: Ideal for restoring Quad II monoblock amplifiers and Leak preamplifiers, where the EF86 is valued for its low-noise performance, high gain, and exceptional audio clarity.<\/p>\n<\/li>\n
Studio Microphones: Suitable as a replacement tube for vintage condenser microphones, including Neumann U67-type designs, where exceptionally low noise and minimal microphonics are critical for professional recording applications.<\/p>\n<\/li>\n
DIY Audio Projects: Ideal for building high-end tube microphone preamplifiers and other custom audio projects requiring low-noise, high-gain performance.<\/p>\n<\/li>\n<\/ul>\n
Lot Details
When you purchase this item, you will receive the exact set of 4 Tungsram EF86 Vacuum Tubes shown in the photographs. The tubes are marked with the following factory production codes printed on the glass: 3Y, YZ, M4, and BD.
The set includes Tungsram-branded cardboard boxes. Please note that we cannot certify whether these are the original factory boxes supplied with these specific tubes, but they provide excellent protection for storage and shipping.<\/p>\n
Datasheet:<\/span><\/strong><\/p>\n ray Plate with Internal Mesh Shield intage <\/p>\n Tested Strong Fully Functional +<\/p>\n Tungsram Boxes (Condition May Vary) Classification: Reclaimed Vintage Electronic Components. Q: Are these tubes a matched quad? Q: Are these tubes compatible with the 6267? Q: How can I tell if these are genuine Tungsram tubes?<\/span><\/strong> Q: Are these tubes suitable for a Vox AC30? Q: What does it mean that these tubes were tested on a Kyoritsu Tube Tester?<\/span><\/strong> Exclusive set of 4 Tungsram EF86 Vacuum Tubes, professionally tested on a Kyoritsu Tube Tester. Low-noise, high-fidelity audio pentodes with factory codes 3Y, YZ, M4, and BD. Ideal for restoring classic tube amplifiers, vintage hi-fi equipment, and professional audio gear.<\/p>\n","protected":false},"featured_media":14947,"comment_status":"closed","ping_status":"closed","template":"","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"default","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center 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\n Feature<\/td>\n Detail<\/td>\n<\/tr>\n \n Product <\/td>\n Set of 4 Tungsram EF86 Vacuum Tubes (Quad) <\/td>\n<\/tr>\n \n Type<\/span><\/strong><\/td>\n Low-Noise Audio Pentode<\/span><\/td>\n<\/tr>\n \n Socket<\/span><\/strong><\/td>\n Noval (B9A) <\/span><\/td>\n<\/tr>\n \n Filament<\/span><\/strong><\/td>\n 6.3V \/ 0.2A<\/span><\/td>\n<\/tr>\n \n Brand<\/span><\/strong><\/td>\n Tungsram (Made in Hungary)<\/span><\/td>\n<\/tr>\n \nLot Codes<\/p>\n <\/span><\/td>\n 3Y, YZ, M4, BD<\/td>\n<\/tr>\n \n <\/td>\n Construction
\nG<\/td>\n
\n<\/tr>\n\n Condition
\nV<\/td>\n\/ <\/td>\n
\n<\/tr>\n\nTube Tester Used <\/p>\n <\/td>\n Kyoritsu Vintage Tube Tester <\/td>\n<\/tr>\n \nIncluded<\/p>\n 4 Vacuum Tubes <\/td>\n 4<\/td>\n
\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<\/h3>\n
Condition of the Set of 4 Tungsram EF86 Vacuum Tubes <\/span><\/h3>\n
Warranty: The tubes are guaranteed not to arrive DOA (Dead On Arrival). Due to the nature of vintage electronic components that are more than 50 years old, they are sold exactly as described and have been professionally tested on a Kyoritsu Tube Tester to verify proper operation. The pins may show minor signs of oxidation from age, which can be easily removed with standard cleaning and do not affect electrical conductivity or performance.<\/p>\n<\/h3>\n
FAQ<\/span><\/h3>\n
A: Although all 4 Tungsram EF86 Vacuum Tubes have tested Good and are fully functional, they originate from different production batches (different factory codes). They are sold as a professionally tested, fully operational set, but they are not guaranteed to be laboratory matched for transconductance within a 1% tolerance.<\/p>\n
A: Yes. The EF86 is the direct European equivalent of the American 6267 and the Z729. They are fully interchangeable and can be used as direct replacements without any modifications.<\/p>\n
A: The internal construction (gray plates with internal shielding), the glass envelope, the printed “T” logo, and the distinctive yellow lettering are all characteristic features of genuine Tungsram tubes manufactured in Hungary during the mid-20th century.<\/span><\/p>\n
A: Absolutely. The EF86 is at the heart of the Normal channel tone found in early 1960s Vox AC30 amplifiers. Tungsram EF86 tubes are highly regarded for their low microphonics (resistance to mechanically induced noise), making them an excellent choice for combo amplifiers where vibration can be a concern.<\/p>\n
A: It means that we used a classic analog Kyoritsu Tube Tester to verify that the tubes have no internal shorts and that the cathode’s electron emission falls within the normal operating range of a healthy vacuum tube.<\/span><\/p>\n","protected":false},"excerpt":{"rendered":"![\"no11_1.png\"](\"https:\/\/www.radiomuseum.org\/images\/tubesockel_klein\/no11_1.png\")
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