Marantz MS308 - Manual (Page 9)

By far the most common cause of loudspeaker failure, and
one that is understandably not covered by guarantee, is
damage to the voice coils caused by amplifier overload.
This is generally due to the common belief that if a speaker
is rated at more than the amplifier's output rating, there is
no chance of blowing that speaker.............
This is not the case!
A relatively small amplifier (i.e. 20 watts) can damage
speakers like these by "clipping" the signal, a symptom
identified by lack of detail in music and distortion. If this
occurs TURN IT DOWN! If you don't want to blow up your
speakers but want louder sound, please purchase a more
powerful amplifier.
Taking care of your loudspeakers
Cabinet Care
Cabinets should be dusted and lightly polished as required.
Do not use solvent based cleaners, as they may damage
the cabinet surface. Do not expose the cabinets to strong,
direct sunlight, high temperatures, high humidity or allow
them to become wet.
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