So you are into the music: you can recognise a few ragas, a few performers, a few instruments, and are ready to persist with it. You need to keep listening: over the years (!), it will gradually become more clear and less mystifying.
If you are beyond the stage of trying to locate ragas in film songs, you will probably be able to take longer performances of raga music for its own sake. But I suspect that one cannot really do much of that type of listening without bringing in the left brain at some point. I feel this is because all raga music will end up sounding the same unless one makes the effort to understand the framework within which the performer is doing his thing. The left brain analyses: raga, tala (rhythm or beat) are the two basics. The right brain experiences the whole, but one’s enjoyment is doubled when it is informed. If one only uses the right brain, then probably one will be satisfied with semi-classical genres; buy some of the recent issues of music for relaxation or meditation; listen to them till they wear out, buy a couple more. If one develops curiosity about the music, however, then one can go on to building up a collection of recorded music on a sustained basis: and they never wear out!
A Hindustani performance starts in a grandly dignified, very edifying manner. The raga maybe be presented briefly in a few phrases, without percussion (drum) accompaniment, and then the compositions started in slow tempo (vilambit laya), followed by another composition in a faster tempo (drut laya). In full-blown performances, however, it is normal for the initial unfolding of the raga (without rhythm accompaniment) to be a protracted affair: the alap. My Karnatik friends would like to call this a vilap (lamentation), since it is often quite sombre. Many minutes may be spent on just a couple of notes around the base sa, caressing the note and establishing its divine presence. Then a second note is added with reluctance, almost, and further phrases developed within these 3-4 notes. After this, the tempo may pick up, with the audience letting out a collective sigh of voluptious indulgence, and the scale is extended above and below in sequence, and the full range of the raga in 2 or more octaves is expounded, in faster and yet faster tempos, culminating in a brilliant flurry of fast sargam or solfege passages. In the course of this exposition, different tempos and rhythmic themes are explored, although the percussion accompaniment has not yet been added (the table player may, however, add a few rhythmic taps on the edge of his instrument when the jiving just gets too jolly!) . These faster and more rhythmic stages are called the jod (different groupings into phrases with the main notes), and the jhala (groups of main note followed by rapidly repeated drone notes), mainly in reference to instrumental music, however.
After this initial exposition the cycle starts again, with the accompaniment (usually tabla, a twin kettle drum, or the more deep-voiced side drum pakhawaj used in dhrupad to emphasise the solemnity of the style). The listener now has a second performer to appreciate, and the tabla often is given time to show off a little in the beginning itself. There is a parallelism between the unaccompanied alap development and the accompanied bandish (in the case of instrumental music, gat) development. The more proficient the performer, the more variations he can expound.
All these are part of what is known as khayal singing (khayal gayaki), reflecting the prominence given to improvisation and development of the theme by the performer (the Persian or Hindustani word khayal signifies “thought”, “imagination”). The older, traditional Hindu genres were in general more “fixed” in terms of composition, iterations, and variations, characters that are found to this day in the dhrupad genre (or dhruvapada, literally fixed metre or verse). The less constrained khayal style developed in the courts of the Mughal emperors and their tributaries during the 16th century. Some scholars have, however, held that the innovations were already present in the Hindu music, and need not be ascribed to influences from outside the tradition, although the whole cause of classical music (including dhrupad) was undoubtedly advanced by court patronage.
Other styles of vocal music, generally less formalised and less heavy, are known as thumri (associated with dancing), ghazal (poetry expounded in singing), and various folk forms. However, one has never heard of a ghazal being sung in a khayal based performance, although a thumri, a hori (song accompanying the revels of Holi, the spring festival)or a dhun (an “air”) may frequently have a place as a filler or a postscript in a classical performance. The serious listener may not like to divert his attention with these “lesser” forms, but to the average listener they may give some relief, being more lively and dealing with better-understandable emotions in comparison with the austere dedication to pure musical sound in the more rigorous classical genre.
Instrumental music may be easier to get pleasure from, perhaps because the distractions of indistinct words in a strange language are absent. The sitar has been the king of instruments in Hindustani music, with the sarod (a fretless instrument, the strings stopped with the tips of the fingers - or the edges of the nails, ouch!) a close second. The traditional veena or been has been displaced in the North and is now a speciality instrument, although the South Indian veena is the reigning instrument in Karnatic music. The bamboo flute (bansuri) and the santoor (a Kashmiri dulcimer) have also become very popular, for the magical and soothing quality of their sound (good for sleeping off to!). The western violin has also been taken up of late in Hindustani (it became a regular instrument in the Karnatik world earlier), perhaps to the detriment of the traditional esraj and sarangi, which have a dirge-like sound exploited to the fullest extent by our government broadcasting media during times of national mourning! The western guitar has also been adapted and developed to our music, giving a vibrant, lively sound like a sitar.
It is often true to say that many of these instruments have become identified with individual performances who have developed distinct styles and even modified and developed the instruments themselves. Once again, we need to recognise this as a living, changing genre, not set in stone by some savant in the hoary past. In fact, as Bhatkande has written, the existing books on music that have come down to us from past centuries are more or less unintelligible to us, because the system has moved so far in practice. For example, although some of the raga names may sound familiar, it is difficult to say what notes they used. Even in the contemporary world, there are many disagreements (and sometimes heated arguments!) on questions of ragas, notes allowed or prohibited, and so on. All this may drive the taxonomist to distraction, but they are the delight of the dilettante and may give opportunities to surprise others by one’s erudition (even if one cannot perform continuously for five minutes!).