[...] the whole exhibition is a pretence, even a cheat, and certainly a snare, for it is essentially about the representation of music in 17th-century Holland rather than about Vermeer, whose contribution is only one sixth of the paintings, and of the other 20, 19 are from the gallery’s permanent collection. For the 10 weeks of the exhibition’s duration the visitor must pay £7 for admission to 21 paintings that before and after it he could see for nothing. These few are supported by three borrowed pictures that could have reached Trafalgar Square by bus, the irksome little dud from New York, only seven instruments and a handful of song books.

This is an exhibition that has had far weightier publicity than it can stand, seducing the innocent and gullible, and those who come hot foot in expectation of a Vermeer show will be crushingly disappointed — it must, indeed, be more rewarding for the historian of keyboard and stringed instruments, and perhaps for the historian of costume. Only by chance does it raise a point of Vermeer scholarship: according to the inventory of Vermeer’s household possessions made, room by room, 10 weeks after his death, he owned not one single musical instrument of any kind; in whose lofty rooms, then, were the expensive virginals on which his egg-faced women played with their pig’s trotter hands (those of the standing player I saw repainted by Helmuth Ruhemann, the gallery’s conservator, 60 years ago)? Is it possible that these rooms are invented? Alternatively, is it possible that they are more or less real and that these excessively plain women are portraits of the wives or daughters of the house? Were such instruments ever in Vermeer’s possession? Had he sold them to pay the butcher’s bill? Was he so passionate an amateur musician that, deprived of them, he fell into the mortal frenzy of his wife’s account?

The National Gallery has, as it were, done nothing but rearrange its deckchairs so that we can see the band. Two Caravaggiesque paintings by Ter Brugghen set the scene before Vermeer’s birth — raw-faced Dutchmen in the togs of the Italian bravo. From the warped View of Delft by Carel Fabritius (proposed by some to have been Vermeer’s instructor) we may conclude that instruments were, like fish and vegetables, sold from stalls in the street. A handful of Vermeerish subjects by his contemporaries Dou, De Hooch, Metsu and Jan Steen (whose Music Makers on a Terrace — possibly based on a performance by travelling players — seems in its sweet melancholy to anticipate Watteau’s Fêtes Galantes), and another handful of musical merrymakers in paintings so trifling that they should be banished to the basement, make up the number.

Brian Sewell points out there were not many Vermeers on view  in the 'Vermeer in Music' exhibition, but this did make me look at those few in more detail than usual.

I was fascinated to notice for the first time that the strings of the guitar under the player's right hand  in 'The Guitar Player' 1670-72 (The Iveagh Bequest, Kenwood) which you illustrate, are shown in motion- actually blurred. Whereas the further up on the neck, they are clearly defined as lines. Of course Velasquez had already done something similar with the blurred wheel in 'The spinners' 1644-48 (Prado). 

Part of the 'timeless' feel of the best Vermeers must come from his habit  of depicting  actions taking place over time; the playing of musical instruments, the stream of milk that pours for ever without the bowl overflowing,  in 'The milkmaid' (Rijksmuseum), the painter with his model.

A close study of  'The guitar player' also reveals the extreme economy of Vermeer's technique of representing light falling on a variety of surfaces, leaving the spectator unconsciously to supply the missing details. For example, the string pegs on the guitar are shown just as two rows of black and white dots, and the pearl necklace is painted as pale circular tube with highlights at intervals. All the details of the hands, face and cloth are shown as flat areas of colour, blending into adjacent planes, creating an illusion of reality and microsopic detail which isn't actually there; all held together by superb drawing and a flawless composition.

One can argue that this all comes from observing the scene depicted  via the use of a lens, a prism or a camera obscura, but that is to miss the point. Vermeer used whatever means were necessary to seduce us into his quiet, contemplative world, and he succeeds every time.