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SYLVANIA

12AX7 / ECC83 SYLVANIA Long Gray plates Square Getter Tested Tube Made in USA

12AX7 / ECC83 SYLVANIA Long Gray plates Square Getter Tested Tube Made in USA

$98.00 CAD
$98.00 CAD
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12AX7 / ECC83 Baldwin by SYLVANIA Long Gray plates Square Getter Tested Tube 
Made in USA

AMPLITREX Tested – VERY STRONG – Vintage American Sylvania Production

Test Results:

Tube tested on AMPLITREX AT-1000 Tube Tester:

  • Test Conditions: Va = 250V ; Vg = -2V
  • 100% Average: Gm = 1600 ; Ia = 1.2 mA
  • Test Result: VERY STRONG

Tube:

  • Section 1: Gm = 1500 ; Ia = 0.9 mA
  • Section 2: Gm = 1800 ; Ia = 1.2 mA
Additional tests performed:
  • Burn-in / Stability Test: 48h – OK
  • Microphonics: Low. Tested and compliant for use in hi-fi equipment and guitar amplifiers, even in the most sensitive audio stages.
  • Balance: The sections are not perfectly matched. The tube is suitable for hi-fi use in non-critical stages (input or driver) and in guitar amplifiers. Not recommended as a phase inverter or in applications requiring strict balance between sections.
  • Emission Quality: Excellent – Very strong and stable emission, without fluctuations.
  • Short Circuits and GAS: None.

Description

A unique and rare 12AX7 / ECC83 Baldwin produced by Sylvania, characterized by the sought-after Long Gray Plates and Square Getter construction. A configuration typical of early American production and definitely less common than the later versions with short plates and halo getters, it is interesting both for audio use and for vintage tube collectors.

The code 312 952 identifies the Sylvania plant in Emporium, Pennsylvania, and dates the production to the 52nd week of 1959. The Baldwin branding testifies to its original selection for musical equipment, where reliability, stability, and low noise were essential characteristics.

The tube has undergone a 48-hour burn-in and was accurately measured with an Amplitrex AT-1000. The two sections recorded Gm 1500 / Ia 0.9 mA and Gm 1800 / Ia 1.2 mA respectively, confirming an overall very strong emission and a second section above the average reference value. Operation was stable, with no fluctuations, gas, or short circuits.

The low microphonics allow for its use even in sensitive audio stages. It is particularly suitable for hi-fi preamplifiers, input or driver stages, and guitar amplifiers, where it can offer energy, dynamics, and a high headroom. The sections are not perfectly matched; for this reason, the tube is not recommended as a phase inverter or in circuits requiring strict balance between the two triodes.

In terms of sound, this Baldwin/Sylvania presents the classic signature of Sylvania's American production of that era: open, dynamic, and natural sound, with a defined midrange, responsive attack, and clear high frequencies without excessive harshness. In guitar amplifiers, it can enhance attack, articulation, and vintage musicality; in hi-fi equipment, it offers a clean, lively, and well-detailed reproduction.

A proposal of particular interest for those who want an authentic 1959 Sylvania 12AX7 with Long Gray Plates and rare Square Getter, with very strong emission, low microphonics, and carefully selected for immediate use.

Conditions:

  • Condition: Vintage Tubes - Tested and perfectly functional. Provided in our custom box for optimal protection.
  • Functionality: Perfectly operational.
  • Cosmetic condition: Very Good – Markings are clearly legible with slight signs of age. See photos for details.
  • Manufacturing Code: 312 952 → 312 indicates the manufacturer, Sylvania Electric Products Inc., Emporium, Pa. - 952 → 9 (of three digits) → 1959 - 52 → 52nd week of the year

Discover why our tubes 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.

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