Choosing the best sound system amplifier may seem like a daunting task. After all, there are a wide variety of components available in a wide range of prices. Thanks to modern digital technology, just about any sound system amplifier made by a reputable company provides better than adequate sound quality at relatively high volume. All that you need to do is to decide what type of sound system amplifier you want, what features it needs to have, how much you want to spend, and how it sounds.
A sound system amplifier can come in one of four forms — a power amplifier, a pre-amplifier or processor, an integrated amplifier, or a receiver. Power amplifiers take the output from a pre-amplifier and increase its power level so that it can drive speakers. Pre-amplifiers, also known as processors or pre/pros in surround sound systems, provide a connection point for all of your components and process the sound for output to the power amplifier. Integrated amplifiers, whose popularity began to fade with the onset of the 21st century, and receivers contain both a pre-amplifier and a power amplifier in one box, with receivers having an AM/FM tuner. While using a separate pre/pro and power amplifier can offer the best sound quality, it is also the bulkiest and most costly set-up, and, because of this, most home audio systems use a receiver.
Consider how many components you need to connect to your sound system amplifier. For many users, the number of both audio and video inputs and the presence or absence an iPod® connector-based device, dictates which amplifier to buy. Ask yourself if you need advanced features like room equalization, THX compatibility, or support for more than 5.1 channels of surround sound. If you are buying a receiver, one very helpful feature to look for is the presence of "preamp-out" connectors that let you use the receiver as a pre/pro should you choose to buy a power amplifier in the future.
Set a reasonable budget. Although prices vary, better than adequate receivers usually cost between $200 and $500 in 2011, while purchasing a separate pre-amplifier and power amplifier realistically starts at above $1,000. For a home theater system, you should expect to buy an amplifier that costs more than your Blu-ray®, and less than your speakers. Bear in mind that lower cost receivers will cut some corners that will be most evident when attempting to play them at very high volumes and when using them with the highest quality signals.
Once you have determined the models that seem to be appropriate for you, audition them. If possible, listen to different models connected to the same speakers in the same room. This lets you hear differences in the sound system amplifier, as opposed to differences in the speakers and in the rooms, both of which usually have a much larger influence on final sound quality. The best option is to work with a retailer who will let you take the amplifier or receiver with you and audition it in your home with your speakers. That audition is what will ultimately help you determine which amplifier to purchase.