JAN AKKERMAN, lead guitarist of Focus, represents the new breed of European guitarists so long invisible under the veil of the English players. Where the islander tends to base his playing more on the American blues scene and his own contemporaries (legends such as Jeff Beck, Eric Clapton, and Jimmy Page), the continental devotee has influences as far afield as J. S. Bach and Django Reinhardt. Because the European musician tends to be a bit more eclectic in his approach to the instrument, it has taken this country longer to accept him within the ranks of the straight Brit-ish and American rock guitarists. Jan Akkerman’s technique and tone quality combine the subtlety and demand of the classical guitar (on which he is highly accomplished) with the roar and tenacity of the electric instrument (he places well each year in English instrumental polls and was fourth in GP’s 1974 poll). Born 27 years ago in the Netherlands, he is devoted constantly to the guitar, and even as this interlude took place Jan cradled a newly-purchased Martin acoustic.