Last Night's Viewing: Symphony, BBC4; Top Boy, Channel 4

It'll come to all of us in time. To ourselves, we're individuals, sharply particular and idiosyncratic. But to someone a few centuries down the line, we're just another social grouping and our collective tastes fair game for broad-brush generalisation.

Like this, for instance, which cropped up early in Symphony, a four-part series presented by Simon Russell Beale. In 18th-century London, he told us, Haydn's experiments with the form found a receptive audience in "the new middle class, who felt that they'd earned their wealth rather than inherited it, [and] were keen for something new that would reflect their sense of themselves as discerning and cultured".

How exactly would that work, I found myself wondering. Would Mrs Burney turn to Mr Burney and ask "Would you care for the opera tonight, my dear?" And would he then reply, "No, madame, I hanker after modish novelty. Let us take in a musical performance more evocative of our recently acquired status and sensibility"? Or had Russell Beale's sentence packed the complexities of commercial and aesthetic evolution just a little too tightly?

It wasn't his fault. Programmes like this would be impossible without historical précis, even though the result can sometimes sound a little glib. And we probably shouldn't hold it against him either that he was sent out into a choppy stretch of the English Channel on a yacht to tell us about Haydn's arrival in Britain.

Directors absolutely love sticking their presenters in an unexpected pulpit, which was why this study of musical development also saw Russell Beale in a high-vis jacket on a building site, gliding down the Seine on the deck of a bateau-mouche and tucking into braised rabbit with dumplings and cherries after a visit to Haydn's herb garden. This latter section also included an extended symphonic metaphor, with the soup standing in for the opening movement and the main course making a gently braised point about the reconciliation of themes in the final section.

Russell Beale is a class act, though, even if you can never be entirely sure where the acting stops and his own thoughts begin. He did describe Haydn at one point as taking "a musical idea on a journey", which made the composer sound as if he'd just got his own series on BBC4, but mostly, the script was literate and instructive and studded with dry little touches of wit: "As the Sun newspaper of 1794 put it," Russell Beale said, "'his music is exquisite, rich, fanciful, bold and impressive'."

There was the faintest pause between source and quote, just long enough to coax you into thinking about how the Sun newspaper of 2011 might cover the same event. "It was the Hun wot won it", perhaps? Or "Austrian baton-meister gives our boys a Haydn". I'm not in a position to say what you would make of the programme if you already knew a lot about music, but if you don't it offered a pretty enjoyable introduction to the subject.

Top Boy, which started well on Monday night, got better and better as it went on, concluding last night with an episode so tense that there were times when it was hard to watch. Ronan Bennett's script, which declined to demonise anyone (except, possibly, a couple of very nasty white gangsters), finally got you to a point where you were desperate for a drug deal to go smoothly. It put you in a place, in other words, where the choices weren't between good and bad anymore but between bad and much, much worse. And then, having spared us the very worst we feared, it showed you how the cycle would start all over again.

The drama involved virtually no preaching at all, but a sense of morality was everywhere, as bad conscience flickered in the face of the toughest characters and grief hit the culpable and the blameless alike. Best of all, it always found a little time for something other than plot, whether it was banter on stairwells or the melancholy beauty of the city at night. Seriously good television.