The basic building blocks of the TransTube® sound are the exclusive designs of the preamp and power amp. The preamp section tailors gain to meet the need for any amount of drive, from crystal clear to thick, smooth sustain. The power amp reacts just like a tube output section by responding to the preamp with natural compression that increases as the amp gets louder. With TransTube, you get a killer amp with widely ranging dynamics and natural “grit, ” just like a tube amp! 8 inch super-duty Blue Marvel® speaker. Two switchable channels: clean and lead. Packed Weight: 21 lb (9.53 kg). Packed Length: 17.87 (45.39 cm). Packed Width: 10 (25.4 cm). Packed Height: 15.62 (39.67 cm).