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GEC

Genalex (GEC) B749 12AU7 / ECC82 - Original UK - Amplitrex Tested - Rare Vintage

Genalex (GEC) B749 12AU7 / ECC82 - Original UK - Amplitrex Tested - Rare Vintage

£331.00 GBP
£331.00 GBP
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Genalex (GEC) B749 12AU7 / ECC82 - Original UK - Amplitrex Tested - Rare Vintage

Original UK Genalex / GEC B749 example, nowadays difficult to find on the market, offered as an authentic vintage valve, professionally tested and fully functional.

Description:

This Genalex (GEC) B749 12AU7 / ECC82 represents one of the rarest and most sought-after versions of the original British production.

The B749 designation identifies a special Genalex/GEC selection designed to meet high quality standards. Original UK valves of this series are difficult to find today, especially in structurally sound and defect-free condition.

Original UK copy, not a modern reissue.

Sound Characteristics

Bass: Controlled and compact, with good definition and no artificial emphasis.

Medium: Natural and easy to read, with a balanced and consistent timbre.

Highs: Clean and composed, with good extension and no harshness.

Dynamics: Linear and predictable, with stable behavior.

Soundstage: Tidy and well-focused, with correct separation of the sound planes.

🎧 Use in Hi-Fi Amplifiers

Suitable for:

  • Line preamplifiers
  • Driver stage
  • Instrument amplifiers
  • Applications where historical character and originality are sought UK

🎯 Note for audiophiles and technicians

    This is not a B749 reissue, but an Original UK Genalex / GEC example.

    Offered as a rare and historically significant tube, tested and fully functional, with low microphonics and stable behavior.

    Test Results:

    Valve tested on AMPLITREX AT-1000 Tube Tester:

    • Test Conditions: Va = 250V, Vg = -8.5V
    • Average 100%: Gm = 2200 ; Ia = 10.5 mA
    • Test Result:

    Valve:

    • Section 1: Gm = 1200 ; Ia = 8.8 mA
    • Section 2: Gm = 1100 ; Ia = 6.2 mA

    The Gm measurements are lower than the nominal reference value; however, the valve shows stable operation, absence of abnormal noises and consistent behavior in dynamic tests.

    Additional Tests Performed:

    • Microphonics: Low. Suitable for use in hi-fi and guitar amplifiers, including sensitive stages.
    • Output Quality: Stable – Output is regular and consistent with the measurements taken.
    • Short circuits and GAS: Absent.

    Conditions:

    • Condition: Vintage tubes - Tested and in perfect working order. Shipped in our custom box for optimal protection.
    • Functionality: Fully functional.
    • Cosmetic condition: Good – Lettering partially eroded, but still legible. Valve body in good condition. See photos for details.

    Find out why our valves are different →

    Terms of Sale & Safety

    Sales Terms & Product Safety

    Each vacuum tube is carefully selected, tested, and verified in our laboratory before shipment. Where stated in the listing, test results, matching data, and declared characteristics refer to measurements performed using the specified test equipment and operating conditions.

    Sound descriptions are provided for guidance only and reflect the characteristics generally associated with that particular tube type. Personal sound preferences, tube rolling, or perceived differences between audio systems do not constitute a product defect.

    Before installation, please verify the tube’s electrical and mechanical compatibility with your equipment and follow the manufacturer’s instructions.

    New production and NOS tubes are shipped with a tamper-evident security seal and internal technical documentation to ensure traceability of the product’s condition at the time of shipment.

    Product Safety (GPSR)

    Vacuum tubes are electronic components intended exclusively for use in compatible equipment and must be installed in accordance with the equipment manufacturer’s instructions.

    Due to their historical or vintage nature, certain technical specifications may be based on original datasheets or equivalent technical documentation when documentation from the specific manufacturer is unavailable.

    Use only with suitable equipment. Keep out of reach of children.

    Shipping & Returns

    Shipping & Returns

    We ship worldwide using carefully selected express carriers and protective packaging specifically designed for vacuum tubes.

    If you change your mind, you may exercise your right of withdrawal within 14 days of delivery, where applicable under the relevant consumer protection laws. The product must be returned complete with its original packaging and accessories, in the same commercial condition in which it was received. Return shipping costs are the responsibility of the customer.

    Every returned item undergoes a technical inspection. Installation, use, tube rolling, or any other handling may reduce the product’s commercial value and may affect the refund amount, in accordance with applicable law.

    If you believe the product has a lack of conformity, our laboratory will carry out the necessary inspections and apply the remedies provided by the applicable consumer protection legislation.

    For further details, Customers are invited to consult the “Terms and Conditions” and “Refund Policy” sections of our website, or to contact us before placing an order.

    Vacuum Tubes Treasures
    www.vtt.store | www.vacuumtubestreasures.com
    📧 info@vacuumtubestreasures.com

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    • ATTENTION PLEASE

      Please understand that the writing on the glass of vintage valves has become very delicate over the years and comes off easily. You must handle them with extreme care to avoid this. Wear and damage to the writing on the valves reduces their market value and causes damage. Please exercise extreme caution.

    • ATTENTION PLEASE

      We wish to inform you that any attempts to manipulate shipping destination information in order to obtain lower shipping rates may be considered fraudulent acts. Please provide accurate information and contact us if you have any concerns. We reserve the right to review and, if necessary, cancel orders that we deem to be in violation of our conditions. Thank you for your understanding and cooperation.