I have a 1976 Sunn Concert bass amp. Running it into two 8ohm cabs... 4x10 and a 1x18. Yesterday was the first time I've played it at full volume (6) for any extended period. At 6, I can just barely hear clipping, after 6 the volume doesn't even increase, it just clips more, so 6 is my max. I noticed that the transistors towards the outputs were very hot. Not so hot that they can't be touched but close. There will also be a slight "burning" smell. No smoke whatsoever though. I also noticed that the speaker cables were a bit warm at the back of the amp. I'm using 16 gauge speaker cable. I put a fan facing the heatsink and transistors of the amp and it brought the temp down to about what it would normally be with the volume at two. What I'm wondering is if this is something I should be really concerned about or if having a fan blowing on the amp will be enough to avoid any damage. Also, should I maybe try thicker speaker cable?