Many of the preamplifiers on the market are designed for use in weak signal areas. They can be overloaded by strong signals. If that happens, signals are mixed together inside the amplifier, producing interfering signals that were not received by the antenna and which can result in less reliable reception. In extreme cases, no reception.
If you have many tuners to connect, or long runs of coax, it's possible you may need to consider a distribution amplifier. Until you establish the need, save your money. Here's a fairly simple test that can help you determine if an amplifier should be considered:
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