The Western Electric 91E Integrated Amplifier with wood-case packaging for the pair of Western Electric 300B vacuum tubes. Opening the large wood-sided crate shipped from the factory in Rossville, Ga.

The 300B was introduced way back in 1938 and has stood the test of time for its audio quality to this day with a 40,000-hour expected life. Whilst there are a number of other 300B output tubes ...