I know what your thinking and yes, I know that I can't run my Stiletto without a cab hooked up. My question though is this: turned on my head and was getting my guitar plugged in, when I realized that the head was not connected to the cab. So, my head was on (in standby most of the time) for 3 to 4 minutes without a cab attached. How long does it actually take for damage to occur? My amp seems to be fine so I figure it is. I'm just curious. Also, what is being damaged by not having a load attached?