True NOS Coppia Oro 3-Mica SYLVANIA 6189/12au7 Tubi Maxi Preamplificatore 2 Testato M0367
Sound Profile; The Sylvania (gold lettering, 3-Mica) JHS 6189 (a military-grade 12AU7WA variant), Users describe describe it as having "good detail without edge," providing a clear yet non-fatiguing listening experience.