Picking a good stereo amplifier for your speakers is not a trivial task. You want to ensure that your amp matches your speakers. I will explain some basic amplifier terms and give some pointers to help you pick the best amplifier.
It is difficult to choose the best audio amplifier due to the large number of models. All of these models have different specs. They are based on different technologies and come in all kinds of shapes and sizes. However, you don't need to be an expert to pick the best model. By following some basic rules you won't regret your buying decision.
The most apparent parameter is the size of the amplifier. There are models that are as big as half your living room while some of the newest mini amplifier models are as small as a bar of soap. A large number of amps are the size of a standard rack. This allows your amp to be stacked on top of your other audio devices.
There are some core amplifier technologies available. One technology is called "solid-state". Solid-state amps now account for the majority of audio amplifiers. In the past, tube amplifiers have been popular. Even today tube amplifiers are still available. Unfortunately, tube amplifiers have fairly high audio distortion which describes how much the audio signal is degraded by the amplifier.
Tube amps will have audio distortion of up to 10%. Solid state amplifiers will have lower audio distortion depending on the amplifier technology that is used. The most traditional amps use a "Class-A" and "Class-AB" technology. These amplifiers are also called "analog amplifiers". While amplifiers using these technologies typically have low audio distortion, power efficiency is only 10% to 30%. Power efficiency describes how much of the electrical power is used to amplify the audio as opposed to being wasted as heat. Amplifiers with low power efficiency will require fairly large heat sinks because most of the power is radiated.
"Class-D" amplifiers, however, which are also called "digital amplifiers" have a power efficiency of at least 80% and are smaller and have a smaller power supply than comparable analog amplifiers. The downside is that many digital amplifiers have higher audio distortion than analog amplifiers although some of the latest models employ a feedback mechanism to reduce distortion to levels of 0.05% and below.
When selecting an amplifier, ensure that the output power is sufficient to drive your speakers. The required power will be determined by how much power your speakers can handle as well as the size of your room where you will be listening. There are two values for speaker power handling: peak and average power handling. The peak value shows how much power the speaker can handle for short periods of time. The average value on the other hand describes how much power the speaker can tolerate continuously without damage.
If you have a fairly small listening environment then 20 to 50 Watts of power should be plenty even though your speaker may be rated for 100 Watts or more. Note though that speakers differ in their sensitivity. Typically a low-impedance speaker will be easier to drive to high volume than a high-impedance speaker. Check your amplifier manual to ensure that your amp can drive your speaker impedance.
Lastly, make sure that your amplifier introduces little noise and has a broad enough frequency response. High-quality amplifiers will have a signal-to-noise ratio of at least 100 dB and a frequency response of at least 20 Hz to 20 kHz.
It is difficult to choose the best audio amplifier due to the large number of models. All of these models have different specs. They are based on different technologies and come in all kinds of shapes and sizes. However, you don't need to be an expert to pick the best model. By following some basic rules you won't regret your buying decision.
The most apparent parameter is the size of the amplifier. There are models that are as big as half your living room while some of the newest mini amplifier models are as small as a bar of soap. A large number of amps are the size of a standard rack. This allows your amp to be stacked on top of your other audio devices.
There are some core amplifier technologies available. One technology is called "solid-state". Solid-state amps now account for the majority of audio amplifiers. In the past, tube amplifiers have been popular. Even today tube amplifiers are still available. Unfortunately, tube amplifiers have fairly high audio distortion which describes how much the audio signal is degraded by the amplifier.
Tube amps will have audio distortion of up to 10%. Solid state amplifiers will have lower audio distortion depending on the amplifier technology that is used. The most traditional amps use a "Class-A" and "Class-AB" technology. These amplifiers are also called "analog amplifiers". While amplifiers using these technologies typically have low audio distortion, power efficiency is only 10% to 30%. Power efficiency describes how much of the electrical power is used to amplify the audio as opposed to being wasted as heat. Amplifiers with low power efficiency will require fairly large heat sinks because most of the power is radiated.
"Class-D" amplifiers, however, which are also called "digital amplifiers" have a power efficiency of at least 80% and are smaller and have a smaller power supply than comparable analog amplifiers. The downside is that many digital amplifiers have higher audio distortion than analog amplifiers although some of the latest models employ a feedback mechanism to reduce distortion to levels of 0.05% and below.
When selecting an amplifier, ensure that the output power is sufficient to drive your speakers. The required power will be determined by how much power your speakers can handle as well as the size of your room where you will be listening. There are two values for speaker power handling: peak and average power handling. The peak value shows how much power the speaker can handle for short periods of time. The average value on the other hand describes how much power the speaker can tolerate continuously without damage.
If you have a fairly small listening environment then 20 to 50 Watts of power should be plenty even though your speaker may be rated for 100 Watts or more. Note though that speakers differ in their sensitivity. Typically a low-impedance speaker will be easier to drive to high volume than a high-impedance speaker. Check your amplifier manual to ensure that your amp can drive your speaker impedance.
Lastly, make sure that your amplifier introduces little noise and has a broad enough frequency response. High-quality amplifiers will have a signal-to-noise ratio of at least 100 dB and a frequency response of at least 20 Hz to 20 kHz.
About the Author:
Gunter Fellbaum has been developing audio and electronic products for over a decade. You can find additional information about t-amp models and stereo amplifier from Amphony's website.
