The distortion and speaker-damping characteristics of a tube amp with an output transformer matched to the speaker load is hard to replicate with solid-state devices.
Transformers are used to convert between high and low voltages, to change impedance, and to provide electrical isolation between circuits.Although the envelope was classically glass, power tubes often use ceramic and metal.The electrodes are attached to leads which pass through the envelope via an air tight seal.S.) and high power RF transmitters, as a display device in television sets and in microwave ovens.Vacuum tubes, or thermionic valves, are arrangements of electrodes in a vacuum within an insulating, temperature-resistant envelope.There are a large number of tube varieties and uses.This is only a very brief overview and we suggest consulting additional resources if you are interested in additional information. Most good guitar amplifiers use tubes rather than solid-state components. The amplifier is a critical element in achieving the sound the musician desires. Tube amps are warmer, richer and have a more desirable tone than solid-state amps.Many musicians prefer to play vintage Fender, Marshall and Gibson amps.Replacement tubes and transformers are readily available for these amps however there are many boutique amp manufacturers making new tube amps with a vintage sound.Some of the older Marshall amps have an inspection sticker on the top of the chassis which usually has the day, month and year the amp was actually made or inspected. Note, "A" Date Code ran for 18 months (July 1969 to December 1970) so the "B" date Code was never used and has been omitted. The serial number is generally located on the back of the chassis but from 79 to 80 it was on the front panel.From 1969 to 1983 the date code was after the serial number.