Why do you need an amplifier?
A power amplifier is needed to increase the voltage, current, or power of a signal. You need an amplifier when your source maximum output as laptop, smartphone or others do not reach the required level. Measured in watts, poweramp contributes power to the signal. The speaker used this power so it has specific resistance that is measured in ohms and rating in wattage.
Classification of power amplifiers
1. Audio-power amplifiers are also called the small signal power amplifiers. They increased the signal’s power levels that have range in audio-frequency.
2. Radio-power amplifiers are also considered power amplifiers with large signals. It is because they raised the signal’s power to higher levels that are ranged in radio frequency. They raised all other specific frequency and narrow band of frequencies but excluding the rest of the frequencies.
Public address systems always use an audio amplifier as well as other reinforcement systems for concert and theatrical sounds. This includes all others like those used in home-theater and stereo systems. Instrument amplifiers include the following: electric keyboard amplifier, guitar amplifier, music amplifier and stereo amplifier.
In some cases, the amplifier of the instruments is integrated into one amplifier “head” that contains an electronic effects, preamplifier and tone controls. Musicians are able to create unique performance using music amplifier. Power amplifier in a stereo amplifier has left and right speakers and a single “monoblock” channel power amplifier to drive a great sound.
What amplifier to buy?
Before you purchase an amplifier, consider for these specifications:
Power output means how loud is the music coming from the amplifier. The larger the room, generally you want more power. However, you do not need as much power as you want. Sensitivity of the speaker has a big influential effect.
Total Harmonic Distortion + Noise (THD + N) measures how much is the effect of the amplifier on the output of sound output. The lower numbers are better as they are the closer to the sound of the original recording. Signal to Noise Ratio (SNR) The goal is to make this background noise imperceptible. You want to hear more music and less noise. The bigger numbers are better!
Crosstalk determines how much of the left’s undesirable signal is mixed with right output. More crosstalk makes it more difficult to determine the effect of placement of instruments like stereo separation. Larger numbers following the minus sign is bad for it means that the stereo separation is greater. Inputs/Connections all have advantages and when there are a few options to choose from an audio amplifier that provides the best sound quality.
Before buying, aside from looking for the above features, consider and compare prices online. This is the ultimate option to get the best deal.