6SN7 GTB Baldwin by SYLVANIA Tested Balanced Tube Black Plates Halo Getter Made in USA '61

6SN7GTB Baldwin by SYLVANIA – Tested Balanced Tube – Black Plates – Halo Getter – Made in USA ’61 AMPLITREX Tested – VERY STRONG – Balanced Sections – Vintage American Sylvania Production Single tube 6SN7GTB Baldwin by Sylvania, Made in USA 1961 production, selected for compatible hi-fi and musical applications that require stability, good electrical performance, and authentic vintage Sylvania sonic character. The construction is typical Sylvania for the era, with black plates, top halo getter, top getter flashing, black base, and well-preserved green Baldwin silkscreen. General aesthetic conditions are excellent, with minimal signs consistent with age and vintage use. See photos for details. The tube has been tested on an Amplitrex AT-1000 Tube Tester with a VERY STRONG result and features balanced sections, an interesting characteristic for circuits where the internal consistency of the double triode is an important element. Microphonics are standard level, suitable for normal hi-fi and compatible musical applications. The tube is fully functional, stable, and free of short circuits or gas. From a sonic perspective, it offers a full, stable, and musically balanced rendition, with controlled bass, natural mids, clean highs, and an organized soundstage. The character is typical of vintage American Sylvania production: solid, fluid, and well-defined. Suitable for preamplifiers, driver stages, phase splitters, and circuits compatible with 6SN7 / 6SN7GTB. A truly tested vintage American tube from Vacuum Tubes Treasures, ideal for those seeking a strong, balanced 6SN7GTB Baldwin by Sylvania with an authentic sonic character. Test Results: Tubes tested on Amplitrex AT-1000 Tube tester: Test Conditions: Va = 250V, Vg = -8V Average 100% Gm = 2600 ; Ia = 9.0 mA Tube #22: Section 1: Gm = 2500 ; Ia = 9.0 mA Section 2: Gm = 2500 ; Ia = 9.4 mA Additional Tests Performed: Microphonics: Standard. Tested and suitable for use in hi-fi and guitar amplifiers. Recommended for use in V2, V3, V4, as a driver or in less critical stages. Not recommended for V1 or in very high-gain positions particularly sensitive to microphonics. Emission Quality: Excellent – Very strong and stable emission, without fluctuations. Shorts and GAS: Absent. Condition: Condition: Vintage Tube - Tested and fully functional. Supplied in our custom box for optimal protection. Functionality: Perfectly operational. Cosmetic Condition: Excellent – Markings well-preserved, minimal signs of age. See photos for details. Manufacturing Code: 312 113 - 312 → Sylvania Electric Products Inc., Emporium, Pa. - 113 → 1 (out of three digits) → 1961 - 13 → 13th week of the year Discover why our tubes are different →