This amp rocks. it is super versatile. It's sound is really close to the old MarkBass F500, except is much more versatile. I have used this amp for only 2 weeks, need to sale your gain my loss. The 500W Gallien-Krueger MB Fusion tube preamp incorporates the same all-tube preamp of the GK Fusion 550 and maintains the amazing portability of the MB2-500. The ultra-light bass amp delivers 500W at 4 ohms, 350W at 8 ohms, and is equipped with an all-tube, 3x12AX7 preamp. The GK MB Fusion bass head also has a 4-band active EQ, variable contour with mid frequency select, and Deep and Bright switches, so you've got total tonal control. Specs: 500W Digital power amp All tube preamp (Three 12AX7s) w/ 4-band Active EQ Footswitchable Boost w/ Volume control Variable contour with mid frequency select Deep and Bright switch Mute switch Active/passive switch (-14dB) Effects loop Line out, headphone out and Tuner out XLR out with pre/post EQ and ground light 2 Speakon outputs Footswitch included Asking $585 Shipped. check, money order or bank deposit I will post a pic in the next couple of days.