Thank you Leo!
Is it ok to turn the amp on and out of standby without a cab? Just don't unplug and plug in a speaker cab while on? Sorry for so many questions. I'm going to try and run it through my P.A setup and want to be safe.
Yes it's correct, however it's not recommended to hot plug and cabinet connect/disconnect shall be done during poweroff or standby.
The amp can be run without any cabinet connected (make sure no cable is connected on the back).
For extra safety you can put the global master volume also to zero.