Peavey Transtube Rage 158 Combo amplifier for electric guitar. A combo amplifier combines, as its name suggests, speaker and amplifier in one device and all you need to do is connect it to the power. You can use it for practice at home as well as for rehearsal/recording in a studio or live performances. In this case, it has a 1 x 8" speaker and has a power of 15W.