Peavey invective.MH Mini Amp Head Lamp head for electric guitar. The head is essentially the amplifier, but without the speaker to reproduce the sound. It is not necessary to connect the head to a speaker in order for it to work, but in order to practice, you will need to connect headphones or speaker cabinet. The characteristic of being lamp means that it operates with tubes, commonly known as bulbs, so it has a warmer and more natural sound. A head can be used for practice at home as well as for rehearsal/recording in a studio or live performances. In this case, it has a power of 20W.