300B
Encyclopedia
The 300B is a directly heated power triode
using a four pin base, introduced in 1937 to amplify telephone signals. It measures 6.4 inches high and 2.4 inches wide, and has a 40 watt anode
dissipation. In the 1980s use of 300Bs by audiophile
s had grown. The 300Bs used by these audiophiles were used home audio equipment. The 300B has high linearity, low noise and good reliability. It is often used in single-ended triode
(SET) audio amplifiers. These SET amplifiers output about eight watt
s, while a push-pull pair of 300Bs can output 20 watts.
Current manufacturers of new 300B tubes, and tubes that have similar characteristics include EH Electro Harmonix, Emission Labs - EML, JJ Electronics, KR Audio, Shuguang, Sovtek
, Svetlana
, TJ FullMusic and Westrex Corporation. Prices for new 300B tubes range from $175 to $900 per matched pair.
Triode
A triode is an electronic amplification device having three active electrodes. The term most commonly applies to a vacuum tube with three elements: the filament or cathode, the grid, and the plate or anode. The triode vacuum tube was the first electronic amplification device...
using a four pin base, introduced in 1937 to amplify telephone signals. It measures 6.4 inches high and 2.4 inches wide, and has a 40 watt anode
Anode
An anode is an electrode through which electric current flows into a polarized electrical device. Mnemonic: ACID ....
dissipation. In the 1980s use of 300Bs by audiophile
Audiophile
An audiophile is a person who enjoys listening to recorded music, usually in a home. Some audiophiles are more interested in collecting and listening to music, while others are more interested in collecting and listening to audio components, whose "sound quality" they consider as important as the...
s had grown. The 300Bs used by these audiophiles were used home audio equipment. The 300B has high linearity, low noise and good reliability. It is often used in single-ended triode
Single-ended triode
A single-ended triode vacuum tube electronic amplifier uses a single triode to produce an output, in contrast to a push-pull amplifier which uses a pair of devices with antiphase inputs to generate an output with the wanted signals added and the distortion components subtracted...
(SET) audio amplifiers. These SET amplifiers output about eight watt
Watt
The watt is a derived unit of power in the International System of Units , named after the Scottish engineer James Watt . The unit, defined as one joule per second, measures the rate of energy conversion.-Definition:...
s, while a push-pull pair of 300Bs can output 20 watts.
Current manufacturers of new 300B tubes, and tubes that have similar characteristics include EH Electro Harmonix, Emission Labs - EML, JJ Electronics, KR Audio, Shuguang, Sovtek
Sovtek
Sovtek is a brand of vacuum tube owned by Mike Matthews's New Sensor Corporation and manufactured in Saratov, Russia. They are often used in guitar amplification and include the popular variants of the 12AX7, EL84, EL34, and 6L6 models...
, Svetlana
Svetlana
Svetlana is a common Slavic female name, deriving from the Russian word свет svet, which translates into English as "light", "shining", "pure", or "holy", depending upon context. The name was coined by Alexander Vostokov and popularized by Vasily Zhukovsky in his eponymous ballade, first published...
, TJ FullMusic and Westrex Corporation. Prices for new 300B tubes range from $175 to $900 per matched pair.