Hi folks,
After further investigation:
SST SQ versions of the (4B has 1 fuse) the (7B's have NO fuses), (14B - 1 fuse), (28B's NO fuses), (3B - 1 fuse), (2B LP - 2 fuses), (2B SST - 1 fuse), (9B - 2 fuses per channel), (6B - 2 fuses per channel).
All fuses are on the AC power side only and are NOT in series with the audio circuit path.
James