I wouldn't worry about that. Although it may seem counter intuititive, you are more likely to damage a speaker by using an underpowered amplifier than an over powered one. This is because an underpowered amp might be driven into clipping. When this happens, the resulting waveforms are extremely rich in high frequency harmonics which can damage the tweeters in your speakers. As long as you keep the volume within less than ear bleeding levels, you probably are quite safe using your speaker combination.

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The Soundhound Theater