Selecting Home Audio Power Amplifiers
Quality sound is very important in a home entertainment system. Whether you want your home to sound like you're at a concert or in a movie theatre, you will need to find the right equipment. A hi-fi system brings you closer to this reality, while an amplifier can help you to get the most out of the system.
What is an amplifier?
Amplifiers are to electrical signals what magnifying glasses are to microscopes. Stereo amplifiers (amps) pick up electrical signals from audio devices and increase their power so that they can play on loudspeaker systems.
What specifications should I look for in an amplifier?
- Connections - Pick a receiver with a couple of HDMI inputs. HDMI allows one cable to carry audio and video signals. Aside from the HDMI, you should have RCA connectors for CD players and others devices that do not use HDMI. An HDMI connection that offers 4K resolution is highly desirable.
- Channels are the number of speakers that can connect to the power amplifier. To get quality surround stereo sounds, you might need at least a 5-, 8-, or 7-channel amplifier. A 16-channel system means that it can handle up to 16 different signal connections.
- Power output - The amp receiver has different power outputs and choosing the right one will depend on your speakers and the budget. It becomes slightly confusing to follow technical terms such as kHz and watt RMS. The two terms represent the frequency response and continuous power rating. The RMS rating can give you a better view of the true power of the amplifier. Speakers that have low sensitivity (measured in decibels, dB), will need more power from an amplifier.
- Impedance - Speakers have a built-in resistance against the electrical power coming from the amplifier. Sound devices measure the resistance in ohms. When the resistance is high, the amplifier responds by cutting back the power that it sends. When there is little resistance, the amp keeps pumping out power. A power amplifier that doesn’t have a lot of power will burn out when you use it on a speaker that has a high resistance.
- Sound formats - Look for the surround experience before considering other formulations. At the basic level, the receivers offer Dolby Digital surround format. There are more advanced formats such as Dolby Atmos, DTS-HD Master Audio, and Auro 3D Audio.
- Space - Find out where you are going to place the amplifier inside your home. Other factors that will affect the amp placement include your speaker arrangement and whether the amplifier will blend in with the rest of your décor. You might need to add a dedicated hi-fi stand in your budget.
- Other features - Some receivers can allow you to stream audio files and video from the internet using a Wi-Fi connection or an ethernet cable. Others let you connect to your phone or other Bluetooth-enabled devices.