Comparisons of text hotline volume and efficiency are hard to come by.

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This is meant to improve sound quality and maximum volume, while optimising power efficiency and protecting the driver.

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The speakers are equipped with onboard DSP, for maintaining accuracy and efficiency at all volume levels, and high-quality, custom-designed neodymium loudspeakers. iLoud is equipped with a bi-amped 4-driver array, and iLoud MINI with a pair of full-range speakers.

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In the National Health Service, the government has resisted the Old Labour approach of caring only about the volume of spending rather than its efficiency.

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Aid volume, however, is rarely matched by efficiency.

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Efficiency is sometimes the most important metric and increases when volume goes up and costs go down.

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