Who needs this when the classics are already bursting with sex?

Forget naked flesh and heart-throb tenors, says Ivan Hewett - the real eroticism is in the music

In all the earnest debate about how to "sex up" classical music, one thing is never mentioned - sex itself. And yet what more potent force could there be for getting new people into classical concert halls?

The market, not sharing the squeamishness of the debaters, has seized on this obvious fact with relish. Suddenly, we're surrounded by glamorous young violinists, cellists, singers and - believe it or not - bassoonists.

If you don't believe it, look at www.beautyinmusic.com, where you'll find pictured a generous acreage of musically-gifted pulchritude, listed by instrument. Among the violinists there's Linda Brava, rather better known for her centrefold appearance in Playboy than for playing in the orchestra of the National Opera of Finland.

The site lists only women, but in the musical world the men are getting the same treatment. Twenty years ago, virtuoso violinist Joshua Bell led the way when he was pictured on the cover of his first CD in eye-wateringly tight jeans, leaning over a motorbike.

More recently, there's been a whole procession of heart-throb tenors. Two in particular have stood out: the Maltese Joseph Calleja, much praised in this paper for his effortless impersonation of the philandering Duke in Verdi's Rigoletto. And there's the Mexican Juan Diego Flórez, who recently released a much-praised album of virtuoso Rossini arias. What they have in common is that mix of dark, soulful looks and stubble that indicates "smouldering".

About time, some will say, depressed at the sight of so much resolute unsexiness in classical music. Just think of those orchestral musicians, perspiring in their tight funereal black.

Think of the grimly serious maestri, some of whom, like the veteran "early music" conductor Nikolaus Harnoncourt, have never been seen to smile. It's an image that reinforces a widely held view of the music itself.

As feminist musicologists keep reminding us, classical music since the 19th century has been configured by male "maestri", male critics, male performers, who've propagated a very male view of the art - severe, formal, intricate, with "feminine" things such as chromatic harmony and dance rhythms kept within decent bounds.

Those things are there, to be sure, but they're always "mastered" by the strict form they're embedded in. In short, classical music appeals to the brain; whereas pop appeals to the solar plexus, or somewhere even lower than that.

You can see the contrast at its most blatant in the 1950s. That was when a group of young avant-gardistes emerged who wanted to systematise classical music, so that it would be as tough-minded as the sciences.

People such as Pierre Boulez and Henri Pousseur liked to be photographed next to blackboards covered in graphs and number charts, and the splintered rhythms of their music seem deliberately designed to banish any trace of the body. Meanwhile, in pop music, the body and sex moved centre-stage, as the decorous sound of the crooners was shoved aside by rock and roll.

So, one way or another, the idea has taken root that classical music in itself is completely sexless, and needs an urgent transfusion of this life-giving elixir from the marketing department.

Which is really a travesty of the truth, because classical music is mostly full of sex, or to put it better, eroticism - it's just that it's hidden, buried in music's grammar.

Every time you hear a dissonance (a tense-sounding interval or chord) melt into a consonant one, you're hearing the basic erotic pattern of arousal and relief. That's true even in the chaste polyphony of Renaissance church music (which is why some of it doesn't sound half as chaste as it ought to).

But where that pattern is spiced up with really grinding dissonances, or where it's repeated in ascending sequences, each repetition more intense that the last, then the sexual connotation becomes blindingly clear.

Italian madrigals of the early 17th century are full of these sequences, often leading to a particularly scrunchy dissonance at the phrase "I die upon your breast" - a favourite euphemism for orgasm.

In the 19th century, as the theme of "unrequited" love took hold, this process naturally took on a frustrated quality. In Schumann and Brahms, sex is transmuted into sentiment; in Wagner, it thrusts itself forward more insistently than ever.

There are moments in Wagner's Tristan and Isolde where it seems as if all the eroticism of humanity has been poured into one super-charged phrase. The tension, the agonised delay, purges the erotic quality of any sense of the body.

You could say that classical music has sex on the brain, which, as D H Lawrence said, is a very bad place to have it. Bad or not, it makes for something jarringly out of tune with current notions of sexiness.

How on earth can you combine the sublimated, secret yearnings of Brahms's chamber music with the up-front sexiness of, say, Bond? The short answer is, you can't. They belong to different worlds. It would be like adding lip gloss to the Mona Lisa.

In any case, is the alleged unsexiness of classical music performers such an open-and-shut case? Many of them are just plain dull, to be sure, but isn't the appeal of conductor Lorin Maazel basically erotic, with its mix of refined pleasure and power? Or take someone such as the young Martha Argerich, with that flaming, unruly hair and that mesmerising power.

You might say classical performers are rarely good-looking, but since when has that been a bar to genuine sex appeal?

The example of the greatest sex symbol classical music has ever produced - Franz Liszt - shows that looks are hardly the most important thing. True, Liszt was mesmerisingly good-looking when young, and when he strode on to the stage, his sword of Saint Stephen clanking at his side, and slowly peeled off his gloves, the ladies swooned.

But, 30 years later, Liszt had a facial wart to rival Oliver Cromwell's, and was routinely dressed in an abbé's vestments. Yet he still fascinated women (and not elderly ones either). One of his admirers disguised herself as a man to pursue him across Europe.

Compared with these giant personalities, the sexiness of Bond or Vanessa-Mae seems manufactured. Only a culture that could routinely use the word "sexy" in antiseptic contexts (a "sexy" company logo, for example), could possibly find these vapid creatures alluring.

And I suspect the audiences are with me. Who gets more scented billets-doux, I wonder: the glossy girls of Bond, or craggy old Alfred Brendel, who has more than a suggestion of a twinkle under that furrowed brow? I wouldn't like to bet on it.