As you might expect, a power amplifier increases the power of a signal so that it can drive a loudspeaker, doing the heavy lifting in any situation where amplified music or audio transmission happens. When you are building an amplification system, you’ll primarily be concerned with four main components: your source, such as a microphone, an electric guitar or other instrument, or a radio receiver or other audio equipment; the preamp, which receives the signal from the source and amplifies it sufficiently to be accepted by the power amp while also allowing manipulation (adding “color” or processing effects); the power amplifier, which takes the signal from the preamp and adds enough juice to drive the speaker configuration you’ve chosen; and your speakers to provide optimal sound.
How to Pick the Best Power Amp for You
When you’re browsing the selection and specs to find the best power amplifier for you, you’ll want to pay attention to the power level, in watts. The power level should generally be equal to twice the continuous power rating of the speakers you’ll be using. You’ll also want to determine how many channels you’ll need based on how many speakers you’ll be powering, one to four, or more. And you’ll need to decide which audio mode best suits you: stereo (two sources, each using a channel), parallel (one source, used by all channels) or bridge (two channels bridged together to deliver more power), or all three. Additionally, it’s important to identify which input and output connections you’ll need. After all, even the perfectly selected amplifier won’t do you any good if it won’t facilitate the speaker cables you’re using, or the source cabling you’ll need. Further, when it comes to power level, another consideration is selecting an amp with extra headroom, which is the difference between the normal operating power level and the maximum level your power amp can handle without clipping and distortion. Getting more headroom than is generally required lets you handle audio signal peaks without blowing out your speakers, while consistently providing loud, clean, undistorted audio. Finally, you may want to think about adding a surge protector to keep your power amp safe from unexpected power surges and lightning strikes, and to protect it from damage caused by smaller electrical surges that can happen over time.