selected preamp tube (RT980)
selected preamp tube 7025WA high grade (RT095-HG)
selected preamp tube ECC83WB (RT093)
selected preamp tube 7025WB high grade (RT093-HG)
selected preamp tube 7025/E83CC Redbase (RT-7025)
selected preamp tube 7025 / E83CC (RT030)
selected preamp tube PSVANE ECC83 (PS-ECC83)
selected preamp tube PSVANE ECC83, matched for symmetry (PS-ECC83-SYM)
selected preamp tube (RT003)
selected preamp tube (RT006)
selected preamp tube 12AY7 / 6072a (RT007)
selected preamp tube (RT009)
selected preamp tube (RT090)
selected preamp tube ECC81/12AT7-Cz balanced (RT052)
selected preamp tube 12AT7WC NOS-selection balanced (RT004)
selected preamp tube 12AU7 / ECC82 (RT005)
selected preamp tube 12AU7WA / E82CC (RT065)
selected preamp tube (RT046)
selected preamp tube 12DW7 / 7247 (RT044)
selected preamp tube EF86 / 6267 (RT-EF86)
selected preamp tube 6922 / E88CC (RT-6922)