A Couple of Guidelines In Order To Help Understand The Signal-To-Noise Ratio Of Modern Stereo AmpsAre you looking to buy a new amplifier for your home speakers? You may be dazzled by the amount of alternatives you have. In order to make an informed choice, it is best to familiarize yourself with popular specs. One of these specifications is named "signal-to-noise ratio" and is not frequently understood. I will help explain the meaning of this expression.
When you have narrowed down your search by taking a look at several basic criteria, including the level of output wattage, the size of the amp in addition to the price, you will still have quite a few products to choose from. Now it is time to take a look at a few of the technical specifications in more detail. The signal-to-noise ratio is a fairly key specification and shows how much noise or hiss the amplifier creates.
Evaluating the noise level of different amplifiers can be done rather simply. Just collect a couple of types which you want to compare and short circuit the inputs. Next set the amp gain to maximum and verify the amount of static by listening to the loudspeaker. Usually you are going to hear two components. The first is hissing. In addition, you are going to often hear a hum at 50 or 60 Hz. Both of these are components which are generated by the amplifier itself. Make certain that the gain of the amplifiers is set to the same level. Otherwise you will not be able to objectively evaluate the amount of noise between several amps. The general rule is: the smaller the amount of hiss which you hear the better the noise performance.
If you prefer an amplifier with a small amount of hissing, you may look at the signal-to-noise ratio figure of the spec sheet. Most producers will display this figure. Amplifiers with a large signal-to-noise ratio will output a small amount of noise. One of the reasons why amps generate noise is the fact that they utilize components like transistors as well as resistors which by nature create noise. The overall noise is dependent on how much noise each element creates. Nonetheless, the location of these elements is also vital. Elements that are part of the amp input stage are going to in general contribute the majority of the get more info noise.
Many of recent amplifiers are based on a digital switching topology. They are known as "class-D" or "class-T" amplifiers. Switching amplifiers incorporate a power stage that is continuously switched at a frequency of approximately 400 kHz. This switching noise may cause some amount of speaker distortion yet is frequently not included in the the signal-to-noise ratio which merely considers noise between 20 Hz and 20 kHz.
Producers measure the signal-to-noise ratio by means of setting the amp such that the full output swing can be realized and by inputting a test signal to the amplifier that is normally 60 dB underneath the full scale of the amplifier. Next the noise-floor energy is calculated in the frequency range between 20 Hz and 20 kHz and compared with the full scale signal energy.
Often you will find the term "dBA" or "a-weighted" in your amplifier spec sheet. A weighting is a technique of showing the noise floor in a more subjective fashion. This method was designed with the knowledge that human hearing perceives noise at different frequencies differently. Human hearing is most sensitive to signals around 1 kHz. However, signals below 50 Hz and higher than 13 kHz are hardly noticed. An A-weighted signal-to-noise ratio weighs the noise floor according to the human hearing and is typically larger than the unweighted signal-to-noise ratio.