Imagine the distance between our planet and pluto(the furthest planet away that we know). Now imagine how big the unviverse could be. The distance from the sun to pluto could only be a small dot in size compared to the whole universe.
By virtue of their electrical properties, tubes generate a special waveform when they're saturated, which is why tube engineering has tremendous tonal advantages over solid state or DSP solutions, particularly for crunch and lead sounds. Tubes enter the saturation zone gradually or softly, which lends tube-driven tone its trademark yet totally unique character.