Across:
   6. see 28
   8. He founded Skid Row, Thin Lizzy and the Eagles?! Not that last one! (4 6)
  10. No evil as demented as 'nation' (8)
  11,12. He would captain the West Indies and direct well, while taking overs and getting lots of runs (5 7)
  12. see 11
  13. Key aspect of piano string in tone's production (7)
  15,20dn. Chemist and engineer from vehicle pound, old-school (4 5)
  17,21. American writer of Jaws blamed in mauling (5 7)
  18. Gamble with a not-yet-final version? (4)
  19. Ben has modulated to G#! (7)
  21. see 17 across
  25. Like 'M' or 'N' as a letter, primarily (5)
  26. Mysterious foe to dux bested in cunning (8)
  27. see 3 down
  28,6. He wrote of an Israel heroically founded and run, so lie spread (4 4)
Down:
   1. Brother briefly takes ill in rough sort of pad (6)
   2. Up the back, grasp in algebra limited (6)
   3,27ac. Blues singer had nothing, was in ruins (5 10)
   4. British labour leaders suffer badly as they make hollow threats (8)
   5. Seconds not to be eaten in restaurant in period of observance (8)
   7. Reveals random number (7)
   9. Injured and short of energy, Serena gets close (5)
  14. Pal using Caesar cipher to find Bandit's bike (3)
  16. Greek protected by China then, I anticipate (8)
  17. Harsh jail arrangement contains no good, and comes to no good (8)
  18. Will Lorde brighten up a bit in "Swagman" piece? (7)
  20. see 15 across
  22. Interim work on the boards (6)
  23. One should keep cool in returning faux OBE citations (6)
  24. 275 year old German writer, cut short, goes old-school (5)