Just to be clear Bob. I am only advocating 2x speaker rating over nominal amp power for guitar speakers and then really only for VALVE op stages of 50W or more. The "classic" AC30 EL84 stage will never deliver more than about 40W no matter what you do (but, N.B. the very early AC30s used Goodmans 15W 12s and they DID burn out. )
The guitar amplifier WILL be overdriven and valves tend to "beat" thermal compression that would otherwise protect VCs driven from transistors.
Many, many years ago we had a pair of KEF Chorals and the tweeters would pop if the tape was dropped early onto the heads in fast wind mode (Quad 303 drive IIRC) a couple of fuses save that situation. That is a case of perfectly match speaker power and PA but a non-standard signal that you would never encounter in a domestic setup.
In an ideal world, speakers are selected to produce a wanted SPL at X mtrs with some headroom determined by the clients pocket! It then becomes a simple matter to decide upon suitable amplifier power. But of course! With itinerate musos "ideal" never happens.
Dave.
The guitar amplifier WILL be overdriven and valves tend to "beat" thermal compression that would otherwise protect VCs driven from transistors.
Many, many years ago we had a pair of KEF Chorals and the tweeters would pop if the tape was dropped early onto the heads in fast wind mode (Quad 303 drive IIRC) a couple of fuses save that situation. That is a case of perfectly match speaker power and PA but a non-standard signal that you would never encounter in a domestic setup.
In an ideal world, speakers are selected to produce a wanted SPL at X mtrs with some headroom determined by the clients pocket! It then becomes a simple matter to decide upon suitable amplifier power. But of course! With itinerate musos "ideal" never happens.
Dave.