Are you searching to get a new a set of cordless speakers for your home? You might be dazzled by the amount of options you have. In order to make an informed choice, it is best to familiarize yourself with frequent specs. One of these terms is called "signal-to-noise ratio" and is not frequently understood. I will help explain the meaning of this expression.
As soon as you have narrowed down your search by glancing at a few fundamental criteria, such as the amount of output power, the dimensions of the speakers in addition to the price, you are going to still have quite a few products to choose from. Now it is time to take a look at a couple of the technical specifications in more detail. One important parameter of wireless speakers is the signal-to-noise ratio. To put it simply, the signal-to-noise ratio describes how much hum or hiss the loudspeakers are going to add to the music signal. This ratio is typically shown in decibel or "db" for short.
Evaluating the noise level of different sets of cordless loudspeakers may be accomplished rather easily. Simply gather several versions that you wish to compare and short circuit the transmitter audio inputs. Afterward set the cordless speaker volume to maximum and check the amount of static by listening to the speaker. By and large you are going to hear 2 components. The first is hissing. In addition, you are going to frequently hear a hum at 50 or 60 Hz. Both of these are components which are created by the cordless speaker itself. After that compare different sets of cordless speakers according to the next rule: the lower the level of noise, the higher the noise performance of the wireless speaker. However, bear in mind that you must put all sets of wireless loudspeakers to amplify by the same level to evaluate different models.
If you prefer a couple of cordless loudspeakers with a small amount of hissing, you may look at the signal-to-noise ratio number of the data sheet. Many producers are going to publish this figure. wireless speakers with a large signal-to-noise ratio will output a small amount of noise. There are a number of reasons why cordless loudspeakers are going to add some form of noise or other unwanted signal. Transistors and resistors which are part of each modern cordless speaker by nature produce noise. Typically the components that are located at the input stage of the built-in power amplifier are going to contribute most to the overall noise. Thus manufacturers generally are going to pick low-noise components while developing the cordless loudspeaker amplifier input stage.
A further cause of hiss is the wireless audio broadcast itself. Normally products which employ FM type transmission at 900 MHz will have a fairly high amount of hiss. Other cordless transmitters will interfer with FM type transmitters and create further static. Thus the signal-to-noise ratio of FM style wireless loudspeakers changes depending on the distance of the speakers from the transmitter in addition to the amount of interference. To avoid these problems, newer transmitters use digital audio transmission and typically broadcast at 2.4 GHz or 5.8 GHz. The signal-to-noise ratio of digital transmitters is independent from the distance of the wireless loudspeakers. It is determined by how the audio signal is sampled. Also, the quality of components inside the transmitter are going to affect the signal-to-noise ratio.
Most today's wireless speakers have built-in power amplifiers that include a wattage switching stage that switches at a frequency around 500 kHz. As a result, the output signal of wireless loudspeaker switching amplifiers have a moderately large amount of switching noise. This noise component, however, is typically impossible to hear since it is well above 20 kHz. Yet, it can still contribute to speaker distortion. Signal-to-noise ratio is normally only shown within the range of 20 Hz to 20 kHz. Consequently, a lowpass filter is used when measuring wireless speaker amplifiers to remove the switching noise.
Producers measure the signal-to-noise ratio by setting the built-in amp such that the full output swing may be realized and by feeding a test signal to the transmitter which is generally 60 dB underneath the full scale of the loudspeaker amp. Then the noise-floor energy is measured in the frequency range between 20 Hz and 20 kHz and compared with the full scale signal energy.
Frequently you will find the term "dBA" or "a-weighted" in your wireless loudspeaker parameter sheet. A weighting is a technique of expressing the noise floor in a more subjective way. In other words, this method attempts to state how the noise is perceived by a human being. Human hearing is most sensitive to signals around 1 kHz whereas signals below 50 Hz and higher than 14 kHz are barely noticed. The A-weighted signal-to-noise ratio is generally higher than the unweighted ratio and is shown in the majority of wireless loudspeaker specification sheets.
As soon as you have narrowed down your search by glancing at a few fundamental criteria, such as the amount of output power, the dimensions of the speakers in addition to the price, you are going to still have quite a few products to choose from. Now it is time to take a look at a couple of the technical specifications in more detail. One important parameter of wireless speakers is the signal-to-noise ratio. To put it simply, the signal-to-noise ratio describes how much hum or hiss the loudspeakers are going to add to the music signal. This ratio is typically shown in decibel or "db" for short.
Evaluating the noise level of different sets of cordless loudspeakers may be accomplished rather easily. Simply gather several versions that you wish to compare and short circuit the transmitter audio inputs. Afterward set the cordless speaker volume to maximum and check the amount of static by listening to the speaker. By and large you are going to hear 2 components. The first is hissing. In addition, you are going to frequently hear a hum at 50 or 60 Hz. Both of these are components which are created by the cordless speaker itself. After that compare different sets of cordless speakers according to the next rule: the lower the level of noise, the higher the noise performance of the wireless speaker. However, bear in mind that you must put all sets of wireless loudspeakers to amplify by the same level to evaluate different models.
If you prefer a couple of cordless loudspeakers with a small amount of hissing, you may look at the signal-to-noise ratio number of the data sheet. Many producers are going to publish this figure. wireless speakers with a large signal-to-noise ratio will output a small amount of noise. There are a number of reasons why cordless loudspeakers are going to add some form of noise or other unwanted signal. Transistors and resistors which are part of each modern cordless speaker by nature produce noise. Typically the components that are located at the input stage of the built-in power amplifier are going to contribute most to the overall noise. Thus manufacturers generally are going to pick low-noise components while developing the cordless loudspeaker amplifier input stage.
A further cause of hiss is the wireless audio broadcast itself. Normally products which employ FM type transmission at 900 MHz will have a fairly high amount of hiss. Other cordless transmitters will interfer with FM type transmitters and create further static. Thus the signal-to-noise ratio of FM style wireless loudspeakers changes depending on the distance of the speakers from the transmitter in addition to the amount of interference. To avoid these problems, newer transmitters use digital audio transmission and typically broadcast at 2.4 GHz or 5.8 GHz. The signal-to-noise ratio of digital transmitters is independent from the distance of the wireless loudspeakers. It is determined by how the audio signal is sampled. Also, the quality of components inside the transmitter are going to affect the signal-to-noise ratio.
Most today's wireless speakers have built-in power amplifiers that include a wattage switching stage that switches at a frequency around 500 kHz. As a result, the output signal of wireless loudspeaker switching amplifiers have a moderately large amount of switching noise. This noise component, however, is typically impossible to hear since it is well above 20 kHz. Yet, it can still contribute to speaker distortion. Signal-to-noise ratio is normally only shown within the range of 20 Hz to 20 kHz. Consequently, a lowpass filter is used when measuring wireless speaker amplifiers to remove the switching noise.
Producers measure the signal-to-noise ratio by setting the built-in amp such that the full output swing may be realized and by feeding a test signal to the transmitter which is generally 60 dB underneath the full scale of the loudspeaker amp. Then the noise-floor energy is measured in the frequency range between 20 Hz and 20 kHz and compared with the full scale signal energy.
Frequently you will find the term "dBA" or "a-weighted" in your wireless loudspeaker parameter sheet. A weighting is a technique of expressing the noise floor in a more subjective way. In other words, this method attempts to state how the noise is perceived by a human being. Human hearing is most sensitive to signals around 1 kHz whereas signals below 50 Hz and higher than 14 kHz are barely noticed. The A-weighted signal-to-noise ratio is generally higher than the unweighted ratio and is shown in the majority of wireless loudspeaker specification sheets.
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