Can someone explain to me what they know about tubes in a tube amp?

"Tubes" aka vacuum tubes, are amplification stages. They take a small signal and make it bigger. They require heated wire elements, which means additional circuitry. They also have certain limitations beyond that, probably too much to go into at this point - I don't know how much engineering/electrical knowledge you have....

Anyways, there are different types of tubes, each has different transfer curves, can handle different amounts of plate voltage, and can conduct differing amounts of current, are biased different ways, etc etc.

The common preamp tubes (low current, usually cathode biased) are the 12a?7 family, ie 12ax7, 12at7, 12au7. Common power amp tubes are EL34's, 6L6's, and various types of KT-??'s. Power amp tubes conduct more current and are usually fixed bias.

Additionally, preamp tubes are usually triodes, and power amp tubes are usually pentodes.

Tube amps can have different topologies, and the power tubes can be operated in different "classes". Class A (always on) are the least efficient, but are claimed to sound the best. Class B (one tube on while the other is off) is far more efficient, but can suffer from crossover distortion. Class AB (halfways in between) has less efficiency, but less crossover distortion, so a slightly "better" sound.

Oh, but the talk of classes is less important (despite what many guitarists and gurus and manufacturers would have you believe) than how *well* the amp is designed.

Tubes are less efficient (ie more wasteful in power, generate more heat, etc) than transistors, which is why transistors (ie solid-state devices) are used by just about everyone except guitarists these days.

Anyways, that's probably a little more than you need to know or even want to know, but those are the basics.

Saul

well i don't really know much about them except that they light up and get really hot when you turn the amp on and it gets great tone and a warm sound but your question is very broad so i don't exactly know what your asking but i can tell you tube amps are the best of the best when it comes to sound they blow solid state amps out the water XD