Raedwulf - thanks for your post. It is interesting that for the harp the same terminus technicus is used as with the lute and organ. A further lecture of my dictionary - this time from the English side - shows that to strike a tone is use for further kinds of instruments. It is the same as in German, where it is anschlagen = to strike with a presyllable.
In the Digitrad I only found only two references for striking a harp: DaveO's and in the Model Church, but 12 for playing the harp.
In the King James Version (Blayney ed.) there is only one playing of the harp mentioned (David before Saul), but no striking.
So I see that I should stay with the English lutenist and harpist; a verbal translation of Lauten-/Harfenschläger as -beaters or -strikers would sound a little bit awkward.
DaveO - now I finally know the lyrics of a Yuletide song I've heard so often in films of the season. Thanks.

And thanks to you all, and a happy new year
Wilfried