What is the 6P3S vacuum tube?

The 6P3S (6P3S-E) is a tetrode vacuum tube designed for power (pp) applications. Russian 6L6..

What is a 6P3S substitute or equivalent?

Direct equivalents to the 6P3S include 6L6GC. These share the same pinout and operating envelope, so they can usually be swapped without circuit changes — though batch-to-batch variations between manufacturers (NOS vs current production) may shift the sonic character noticeably.

What are the key specifications of the 6P3S?

Transconductance gm ≈ 6 mA/V, max plate voltage 400 V, max plate dissipation 20.5 W, heater 6.3 V / 0.9 A.

Is the 6P3S still in production?

Production status varies by year and manufacturer. The current Amperatubes catalog classifies the 6P3S as Common availability. NOS (new-old-stock) examples from RCA, Mullard, Tung-Sol, GE, Sylvania and Telefunken trade among collectors; modern production where it exists comes mostly from JJ Electronic, Electro-Harmonix, Tung-Sol (New Sensor), Genalex, and a handful of small-batch makers.

What does the 6P3S sound like?

Russian 6L6.. Sonic character also depends heavily on the circuit operating point, the surrounding tubes in the stage, and the output transformer when present — use the interactive loadline calculator on this page to explore the trade-offs.