The M80's are the most sensitive, but theyre half the ohms of the other speakers, so while they might go louder on the same amount of power they will need a better amp to handle the 4 ohm load. Most recievers now days wont handle a 4 ohm load such as the M80's. especially when you want to get it crankin. however id say the majority of the more expensive ones will handle it, but i doubt they will do the M80's justice.

Just my thoughts.

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