THE KT150 TUBE

摘要

Looking rather different from its predecessors, the KT150 still follows the line of development that started in the late 1930s with the first beam tetrodes, RCA's 6L6 and EMI /Marconi's 'kinkless tetrode', the KT66. Higher-power versions, the 6550 in the US and the KT88 in the UK, were introduced in the mid-1950s and the 1990s brought the beefed up KT90. Then, in 2009, Tung-Sol, now part of the New Sensor empire that embraces the main Russian brands, launched its substantially more powerful KT120. Now, Tung-Sol's KT150 is billed as 'the most powerful octal beam tetrode ever produced', with a plate (anode) dissipation of 70W, against 60W for the KT120, or about 40W for a KT88. It's said that a pair of KT150s can give an amplifier output 'approaching 300W, while the egg-shaped glass envelope improves thermal dissipation and reduces microphony.