RCA 5814A / 12AU7 Balanced Preamp Factory Set Same Codes 1965 - Tested

Superior Sound Supply selling some seriously special stock. This listing features a matched pair of RCA Command Series 5814A tubes, a ruggedized military/industrial equivalent to the standard 12AU7. Precision tested with perfectly balanced results across all triodes, these tubes offer the robust build quality and warm, rich tone sought after by audiophiles and musicians alike.

Technical Specifications

• Brand: RCA (Command Series)
• Model: 5814A (Premium 12AU7 / ECC82 Substitute)
• Type: Medium-Mu Dual Triode
• Plate Type: Black Plate
• Getter Type: Halo Getter
• Test Results: All four triodes tested at 84% on a Precision Model 612
• Matching: Perfectly balanced triode-to-triode and tube-to-tube
• Included: Original Boxes
• Factory Codes: 6513 38J (Same Dates, Factory & Batch)

Condition Details These tubes are in excellent cosmetic and functional condition. The glass is clear with strong, legible branding and logos, indicating they have seen minimal handling. The pins are straight and have been cleaned for optimal contact. Physically, they exhibit the high-quality construction RCA Command tubes are known for, including thick mica spacers and matched internal structures. Functionally, they test strong and balanced at 84% emission across the board, ensuring reliable performance in stereo preamps or phase inverter positions.

Historical & Technical Context The RCA Command 5814A was designed for "special quality" service, meaning it was built to withstand the rigors of military and 24/7 industrial computing applications. For audio users, this translates to lower microphonics, tighter manufacturing tolerances, and a longer lifespan compared to standard consumer 12AU7s. They are widely regarded for their warm sound signature and solid bass response, making them a fantastic upgrade for hi-fi audio equipment and guitar amplifiers requiring a 12AU7/ECC82 type.

Superior Sound Supply Guarantee

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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.