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SYLVANIA

12AX7 / ECC83 Baldwin by Sylvania Matched Quad Long Gray Plates Halo Getter Tubes USA

12AX7 / ECC83 Baldwin by Sylvania Matched Quad Long Gray Plates Halo Getter Tubes USA

HK$1,411.00 HKD
HK$1,660.00 HKD HK$1,411.00 HKD
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12AX7 / ECC83 Baldwin by SYLVANIA – Matched Quad – Long Gray Plates – Halo Getter – Made in USA

Matched Quad – AMPLITREX Tested – Vintage American Sylvania Production

Description

Matched quad of 12AX7 / ECC83 Baldwin by Sylvania, Made in USA production, selected for compatible hi-fi and musical applications where consistent, stable valves with a classic vintage American sound character are required.

Baldwin-branded valves were intended for musical and professional applications, particularly quality electronic organs, where reliability, continuous operation, and consistent performance were fundamental requirements. In this case, the production can be traced back to Sylvania, with Long Gray Plates and Halo Getter construction, a configuration appreciated for musicality, balance, and natural tonal quality.

The quad has been tested and selected in our laboratory using the Amplitrex AT-1000 Tube Tester as a Matched Quad. The matching between the four valves makes it particularly interesting for multi-stage devices, complex stereo systems, and configurations that require uniformity across multiple circuit positions.

Sonically, it offers a soft, natural, and well-organized output, with controlled bass, warm and harmonically rich mids, airy but not aggressive highs, and a stable soundstage. The overall character is musical, fluid, and pleasantly vintage, with good tonal coherence among the four valves.

Suitable for multi-stage tube preamplifiers, integrated amplifiers, compatible phono stages, tube DACs, buffers, line stages, vintage restorations, and instrument amplifiers compatible with 12AX7 / ECC83.

A vintage American selection truly tested and matched by Vacuum Tubes Treasures, ideal for those seeking a consistent, musical, and refined-sounding 12AX7 / ECC83 Sylvania quad.

Test Results:

Valve tested on AMPLITREX AT-1000 Tube Tester:

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

Valve #7:

  • Section 1: Gm = 1400 ; Ia = 0.9 mA
  • Section 2: Gm = 1300 ; Ia = 0.9 mA

Valve #6:

  • Section 1: Gm = 1400 ; Ia = 0.9 mA
  • Section 2: Gm = 1300 ; Ia = 0.8 mA

Valve #3:

  • Section 1: Gm = 1300 ; Ia = 0.8 mA
  • Section 2: Gm = 1400 ; Ia = 0.9 mA

Valve #2:

  • Section 1: Gm = 1300 ; Ia = 0.8 mA
  • Section 2: Gm = 1300 ; Ia = 0.8 mA
Additional Tests Performed:
  • Microphonics: Low. Tested and suitable for use in guitar amplifiers, even in V1.
  • Balance: The sections show overall consistent balance, fully compatible with use in musical amplifiers, in all applications where absolute symmetry between sections is not required.
  • Emission Quality: Excellent – Very strong and stable emission, without fluctuations.
  • Shorts and GAS: Absent.

Condition:

  • Condition: Vintage Tubes - Tested and fully functional. Supplied in our custom box for optimal protection.
  • Functionality: Perfectly operational.
  • Cosmetic Condition: Good – Markings partially eroded, but still legible. Valve body in good condition. See photos for details.
  • Manufacturing Code: 312 239 → 312 indicates the manufacturer, Sylvania Electric Products Inc., Emporium, Pa. - 239 → 2 (out of three digits) → 1952 - 39 → 39th week of the year

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.