Whether for critical listening or even for confidence monitoring, driving loudspeakers into distortion is not good for the devices or the ears.
Sending a clipped (distorted) audio signal into a loudspeaker only serves to rapidly add more heat to its voice coil, hastening its demise. Clipping can come from overdriving any part of the audio chain, from the power amplifier on down to the mixing console or external mic pre-amps.
Too often high distortion is equated with high sound pressure levels, but it shouldn't be that way. Along with all the other criteria for selecting a loudspeaker, if you need higher levels, choose a loudspeaker with a high broadband sensitivity rating and high power handling, and then an appropriately rated power amplifier, if the loudspeaker isn't already "self-powered," meaning that the loudspeaker system incorporates an integrated power amplifier.
Sensitivity is a measurement of on-axis sound pressure level (SPL) with a specified input power to the loudspeaker and at a specified distance from the loudspeaker. An example of such a spec for one particular higher output monitor loudspeaker is 101 dB-SPL, 1 watt, 1 meter, with a power handling of 200 watts with continuous sine wave and 800 watts instantaneous peak.
