Selecting the perfect audio amplifier can be daunting given the huge number of diverse models and technologies. I will aid you understand some of the essential amplifier jargon vocabulary. This information will help you choose the perfect amplifier.
Audio amplifiers are the crucial link between your source such as a DVD or Blu-Ray player and your speakers. An amplifier will convert the relatively weak source audio into a signal powerful enough to drive your speakers.
Depending on your application, you may want to go with a source that already has a built-in amplifier. However, utilizing a separate amplifier will give you more versatility in selecting the type that best complements your speakers. Some of today’s mini amplifier models are small enough to conceal them almost everywhere.
Output wattage is one of the factors that many people will consider first when selecting an amplifier because driving low-sensitivity speakers or driving speakers in large rooms or outdoors requires relatively high wattage. You shouldn't employ an amplifier with significantly higher output power than your speakers can manage. Overdriving your speakers can do irreparable harm to your speakers.
However, amplifier wattage is not everything. Good sound quality is possibly more critical than rare power. A 20 to 50 Watt amp ought to be sufficient for most real-world applications.
There are two conventions for specifying amplifier wattage. The first one specifies how much power the amplifier is capable to supply continuously. That figure is often labeled rms or continuous power. The second number is called peak or maximum power and tells how much the amp can deliver for small bursts. Many people will take a look at the rms power value when choosing an amplifier. On the other hand, music signals are anything but continuous. Consequently choosing an amp that has sufficient peak power handling is just as significant.
There are additional parameters that are more essential than wattage when picking an amplifier. One significant parameter is called total harmonic distortion or THD in short. No amplifier is perfect. There will be some level of signal distortion which is brought about by the amplifier. The amount of distortion is expressed in percent or dB. A smaller distortion number means a lower distortion of the audio signal by the amplifier. The level of distortion will be less than 0.05% for a high-quality amplifier. Consumer type amplifiers have higher distortion figures. Typical figures are up to 10% depending on the output power.
Another figure related to audio quality is known as signal-to-noise ratio and describes the amount of unwanted noise the amplifier will add to the signal. Audiophile-grade amps will have an SNR of 100 dB or higher. Consumer-grade amps will have at least 80 dB signal-to-noise ratio.
There are a number of amplifier technologies available. Modern amplifiers are mostly Class-D amplifiers. Class-D amplifiers have a high power efficiency and waste little energy as heat. Some of today’s mini amplifiers are no larger than a deck of cards. Though, when choosing a Class-D (digital) amplifier, be sure that the amplifier has little distortion and a high signal-to-noise ratio.