This is good fun and useful (and quite addictive :) ). There are two trainers - one for intervals and one for chords. You can set it at different levels ie beginner, intermediate, advanced, professional. The difference between the levels is the variety of different intervals or chords you have to identify. So for example at beginner level you have the intervals unison, major second, perfect fourth, perfect fifth and octave; at professional level you have all the intervals within the octave plus over the octave up to thirteenths. Similarly, with the chords you have at intermediate level - major, minor, augmented, diminished, suspended; at advanced level the 7th chords are added, and so on. You can set the intervals to play low to high or vice versa, random, simultaneous. You can alter the instrument they are played on, the tempo, the root note. The sound quality isn't brilliant but perfectly good enough for purpose. The programme plays you the interval or chord then you identify it from a list of possibles. It's very easy to use. If the sound was a bit nicer I'd have given it 5 stars. Very helpful if you are practicing for aural/musicianship exams.