I bought this unit because I was a working keyboardist and singer for about 25 years until I gave up the late nights, but I missed playing with a band, and now I have one with this little box. I'm playing guitar now and the Trio is just an awesome practice tool. The Trio band never gets sick of playing the song while I practice! You just play chords and rhythm into it, and it comes up with a drum and bass line for you. Teaching it is kind of a learning curve, and some of my guitars work better than others, must be a difference in the sigmal. It will store five different parts for each song you program for intro, verse, chorus, etc. and you can sequence the parts in any order you want. You can store 12 songs on the mini SD card that comes with it and just change cards when you fill one up. You can download a manager ap to store your songs to computer, which you want to do often because it is kind of easy to erase your work by holding the wrong button down at the wrong time, that's one drawback that exists. Once the drum and bass is established you can change to 12 different music genres, blues, rock, fok, etc. and each genre has 12 differnt styles you can switch to. It's kind of like a sequencer, but MUCH easier and faster to program a song. I can usually do a whole song in less than an hour, some faster, some longer. It aslo has a looper with unlimited overdubs, so you can record rhythms, keyboard parts, backup vocals or whatever to back you up. I have to emphasie that everything is EASY and fast to do. The drum and bass samples aren't stellar, but sound decent. There's also a button to simplify the bass line. The active bass is very active and not appropriate for a lot of songs, but there are two more settings, one a bit less active, and one with simple root notes. There are also volume knobs for the bass, drums, and looper. Only one output for all, so you can't mix or EQ them from a console. Kind of too bad about that, it would be nice to have that ability. It also has a built in guitar effects loop so you can use your multi effects pedal while plugged into the Trio. There's also a tempo knob so you can slow down or speed up your track, loops and all. For me, Digitech just knocked it out of the park with this invention. They packed an awful lot of cool stuff into this $300.00 box and it is a LOT of fun to play with. As a fairly new guitar player, I wouldn't be playing nearly as much if I didn't have this thing to practice to. I feel it has improved my playing a lot! For those on a tighter budget, there is a $150.00 version, but it has only three song parts, less genres, and no looper.