Mini combo Promethean. P20 bass amp features a simple 4-band tone control to adjust the tonal character. The included aux input allows you to play along with a connected MP3 or CD player. The headphone out is great for bedroom jam sessions or sound checks at rehearsal. Specs output 20 W @ 8 speaker 8" Speaker controls High, High-Mid, Low-Mid, Low, Master, -10 dB Input Pad i/o's Input, AUX Input, Headphones Out cabinet Closed Back size (mm) 330 (W) x 350(H) x 310(D) weight 7.8 kg.