Philips ECC83 12AX7 NOS NIB Private stock matched pair premium plus TUBES Phono

Philips ECC83 (=12AX7) NOS NIB Private stock matched pair premium plus TUBES for audio and phono stage. - Unused ever. - triangle etched codes Heerlen Holland factory dimpled dish 1971. - Best sounding choice ECC83/12AX7. - Satisfaction guaranteed, as sold to famous musicians in the USA. - Codes and testdata are excellent  : I66 triangle 1E1 1.32-1.7 and 1.45-1.9 mA/v I66 triangle1E1 1.32-1.7 and 1.46 - 1.9 mA/v same batch  AAAAA+++ grade.  The ECC83 high impedance amplifier triode was designed specifically for audio use and has a high amplification factor of 100. Mullard describe the ECC83 as a high μ double triode, having separate cathodes, primarily intended for use as a resistance-coupled amplifier or phase inverter. This valve is still found in todays designs of hi-fi audio amplifiers. In the classic Mullard designs of the 1950s and 1960s the valve's two halves were used as second stage amplification and cathode coupled phase splitter. The phase splitter being required so that the push-pull output stage was driven correctly. The thin glass tube envelope is 21 mm in diameter and, excluding the B9A base pins, is 48 mm tall. References: Datasheet, 3002 & 1040. Type ECC83 was first introduced in 1954. SUMMERSALE reduced prices 25-4-2019/.