The 300B is a directly heated power triode using a four pin base, introduced by Western Electric in 1937 to amplify telephone signals. It measures 6.4 inches high and 2.4 inches wide. It has a 40 watt anode dissipation. In the 1980s the 300B was rediscovered by audiophiles for use in home audio equipment and is known for its high fidelity, low noise and reliability. It is frequently used in single-ended triode (SET) audio amplifiers such as the Cary CAD-1610-SE and the Cayin A-300B.
Due to their rarity and high demand, new old stock (NOS) 300B tubes made by Western Electric from the 1940s–1960s have become collectible items among audio enthusiasts, with price tags in excess of $700 and used tubes selling for over $400.
Current manufacturers of new 300B tubes, and various workalikes include Electro Harmonix, Emission Labs, JJ Electronic, KR Audio, Sophia Electric, Sovtek, Svetlana and Westrex Corporation (which produces a "recreation" of the original Western Electric tube[1]). Prices range from $175 to $900 per matched pair.
From Wikipedia, the free encyclopedia
2/15/08
300B
2/14/08
1L6
The 1L6 is a 7 pin miniature vacuum tube of the pentagrid converter type. It was developed in 
the USA by Sylvania. It is very similar electrically to its predecessors, the Loktal based 1LA6 and 1LC6. Released in 1949 for the Zenith Trans-Oceanic shortwave portable radio, this tube was in commercial production until the early 1960s .
The 1L6 was to be a specialty tube, produced in small quantities by very few manufacturers, mostly Sylvania for use by just a few manufacturers of shortwave portables, such as Zenith - in their Trans-Oceanics - and its short-lived rivals, such as the Hallicrafters TW-1000 and the RCA Strat-O-World and very few others.
Despite the limited application for 1L6, today NOS examples bring relatively high prices. Many radio collectors overcome this expense by using the more commonly available 1R5 with pin 5 cut off.
