Do I need to leave blank rack spaces above/below my gear?

Dangerous gear does not get extremely hot. However, we always recommend leaving blank spaces anyway. More ventilation always equals longer gear life, no matter how hot or cool your gear runs. Do not rack your Dangerous gear next to very hot gear such as power amps, interfaces, tube gear, etc. If you don’t have a choice, then putting it underneath the hot gear is preferable to on top of it.