The only time you want to use an amplifier is if you have an extremely long cable run and your experiencing signal loss over it. Another situation might be where you use splitters to feed the same singal to many receievers. Other than those situations you should probably stay away from amplifiers as they themselves will add some noise to the signal. So, if you don't need an amplifier and you still use one anyway, your just going to make your signal quality worse instead of better by adding more noise.