I recently acquired an Ampeg V4. I am new to all tube amps, but I know that the Ampeg book says they were closer to 120w as opposed to the advertised 100w rating. I'd like to avoid the tube watts vs ss watts arguement...So how many watts should my speaker cab be able to handle to not blow? Perhaps if someone knows the max sound pressure levels of a v4 that would help me pick a speaker?