If you want to use tubes, generally speaking, higher efficiency and higher impedance are desirable.
dB effeciency vs speaker configuration
I want to know the different caracteristics of speaker. Which one of the following technical data would give better musique, less difficulties to the power amp ? Which would give a better match and sound with stereo tube power amp, and, second with a solid state power amp ? Speaker with air vent, or sealed speaker? Speaker with 4 ohm or 8 ohm ? Speaker with 87 dB or 95 dB effeciency ?