RCA 5963 12AU 7 Black Plate Matched Pair - NOS Vintage Vacuum Tubes - Industrial 12AU7 ECC82 Equivalent - Made in USA

Superior Sound Supply selling some seriously special stock. This matched pair of RCA 5963 vacuum tubes represents a premium industrial-grade alternative to standard 12AU7s, featuring desirable long black plates and D-getters. Sourced as New Old Stock (NOS) in their original boxes, these tubes have been precision-tested to ensure they meet the rigorous standards expected for high-fidelity audio and vintage guitar amplification.

Technical Specifications

* Brand: RCA (Radio Corporation of America)

* Model: 5963 (Industrial 12AU7 equivalent)

* Plate Type: Long Black Plate

* Getter Type: D-Foil Getter

* Date Era: Late 1950s - Early 1960s

* Country of Origin: USA

* Condition: NOS (New Old Stock), Matched Pair

* Test Status: Pass for Shorts, Grid Leakage, and Emissions on Precision Model 612

* 88/90

* 90/90

Condition Details

This pair is in exceptional cosmetic and functional condition. Being New Old Stock, the glass is clear with strong, legible flashing and intact logos. The pins are straight and free of corrosion. They ship in their original red and white RCA boxes, which show minor shelf wear consistent with their age. Both tubes have been tested for emissions, shorts, and leakage, and have passed a noise test to ensure they are free from microphonics.

Historical & Technical Context

The RCA 5963 was originally designed as a "computer grade" industrial tube, engineered for high reliability and long service life where standard consumer tubes might fail. It features a special double-layer cathode designed to prevent "sleeping sickness" (cathode interface impedance) during long periods of cut-off. With a peak cathode current of 100mA (versus 60mA for a standard 12AU7) and 0.5W grid dissipation, these are robust performers. They are highly prized in audio applications, particularly as phase inverters or drivers in Fender, Marshall, and Vox amplifiers, offering a reliable, long-lasting upgrade over modern 12AU7/ECC82 equivalents.

Superior Sound Supply Guarantee

Superior Sound Supply Quality Assurance:

Transparency and accuracy are the cornerstones of our business. We ensure every component is vetted so you can buy with complete confidence. Along with Superior Supplies for all of your sounds, We stand on Superior Service, If your not satisfied with our supply we will make it right.

Shipping: Carefully packaged with consistent methods that are proven to protect your item and ensure safe delivery. We primarily use USPS, and FedEx for large or high-value items, and can arrange international shipping to anywhere in the world. Orders are processed and shipped within 1-3 business days of payment clearance. We do not ship on weekends or federal holidays. Orders placed after 2:00 PM CST Friday will ship the following Monday.

Returns:

• New Items: Returnable within 30 days of delivery.

• Used & Vintage Items: Returnable within 30 days of delivery.

General Terms

Items must be returned in original, as-shipped condition with all original packaging and no signs of use. Buyer assumes responsibility for all return shipping costs unless the item was not received as described.

Make sure to check the return policy on each individual listing as some items may be sold "As-Described" and not eligible for a return. We want you to be completely satisfied with your purchase.