RCA 6SN7GTB Preamp Tube 1950s USA - Tested

Superior Sound Supply selling some seriously special stock. This is a genuine vintage RCA 6SN7GTB, a highly regarded American-made dual triode featuring the desirable black ladder Plates and side D-getter construction. Combining the lush, warm signature of RCA black Plates with the improved reliability of the GTB designation, this tube is an outstanding upgrade for hi-fi preamps and vintage amplifiers.

Technical Specs

• Brand: RCA
• Model: 6SN7GTB
• Type: Dual Triode
• Construction: Black Ladder Plates, Side D-Getter, Straight Glass
• Test Results: Passed for Shorts, Opens, and Leakage
• Emission Scores: Triode 1: 88% Triode 2: 94%
• Base: 8-Pin Octal (Black Bakelite)

Condition Details This tube is in excellent condition with strong, well-balanced test results (88% and 94%). The glass is clear with the "6SN7 GTB" type designation clearly etched into the envelope. The silver "RCA Radiotron Electron Tube" printing on the base is crisp and fully legible. The base is tight to the glass with no looseness, and the pins are clean. Internally, the black Plates structure is secure, and the getter flash is healthy.

Historical Context Introduced in the mid-1950s, the "GTB" version of the 6SN7 family was designed with higher Plates voltage ratings and a controlled heater warm-up time, making it the most robust iteration of the tube. Despite these modern improvements, this specific example retains the classic internal architecture—black Plates and side getters—that audiophiles prize for their rich midrange, deep bass, and "holographic" soundstage, distinguishing it from later Gray-Plates coin-base versions.

Superior Sound Supply GuaranteeSuperior 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.