Beginning in 1962, Scott often substituted
(within manufacturing batch-runs) the 7199 for the older 6U8 phase inverter. This required
extensive circuit changes to the amp's phase invert circuitry..
Today, the 7199 is more difficult to locate, and subsequently much more
expensive than the 6U8. For Scott, only the LK-150, exclusively used the 7199 in
all variants.
Glass Miniature type used in high-quality, high-fidelity audio equipment,
particularly in phase splitters, tone-control amplifiers, and high-gain voltage
amplifiers. Requires miniature 9-contact socket. In direct-coupled
voltage-amplifier phase-splitter circuits, the pentode unit drives the triode
unit.
