Are you searching to acquire a brand new a set of cordless speakers for your home? You might be dazzled by the number of choices you have. In order to make an informed selection, it is best to familiarize yourself with frequent specs. One of these specifications is known as "signal-to-noise ratio" and is not frequently understood. I will help explain the meaning of this term.
Once you have narrowed down your search by taking a look at some key criteria, including the amount of output wattage, the dimensions of the speakers plus the price, you are going to still have quite a few products to choose from. Now it is time to look at a couple of the technical specs in more detail. An important parameter of wireless loudspeakers is the signal-to-noise ratio. To put it simply, the signal-to-noise ratio explains how much hum or hiss the loudspeakers are going to add to the music signal. This ratio is usually shown in decibel or "db" for short.
A method in order to perform a simple check of the noise performance of a set of wireless speakers is to short circuit the transmitter audio input and then to crank up the wireless loudspeaker to its utmost. Then listen to the loudspeaker. The static which you hear is produced by the cordless speaker itself. Make sure that the gain of each set of wireless loudspeakers is couple to the same amount. Otherwise you will not be able to objectively compare the level of static between several models. The general rule is: the lower the amount of noise that you hear the better the noise performance.
To help you compare the noise performance, cordless loudspeaker suppliers show the signal-to-noise ratio in their wireless speaker spec sheets. Simply put, the larger the signal-to-noise ratio, the lower the level of noise the cordless loudspeaker generates. Noise is produced due to several factors. One factor is that today's wireless speakers all make use of components such as transistors plus resistors. Those components will produce some amount of noise. Because the built-in power amp overall noise performance is mostly determined by the performance of components situated at the amplifier input, makers are going to try to choose low-noise elements whilst developing the amplifier input stage of their cordless speakers.
The cordless broadcast itself also causes static which is most noticable with products which use FM transmission at 900 MHz. FM transmitters are very prone to cordless interference which is why newer types typically use digital audio broadcast. The signal-to-noise ratio of digital transmitters is dependent mostly on the type of analog-to-digital converters and other parts which are utilized and also the resolution of the cordless protocol.
Many of modern cordless speaker use amps which are based on a digital switching topology. These amplifiers are named "class-D" or "class-T" amps. Switching amps incorporate a power stage which is always switched at a frequency of approximately 400 kHz. This switching frequency is also hiss which is part of the amplified signal. However, modern cordless loudspeakerspecs usually only consider the hiss between 20 Hz and 20 kHz.
Makers measure the signal-to-noise ratio by setting the built-in amplifier such that the full output swing can be realized and by inputting a test tone to the transmitter that is normally 60 dB underneath the full scale of the speaker amplifier. 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.
Another convention to express the signal-to-noise ratio utilizes more subjective terms. These terms are "dBA" or "A weighted". You will spot these terms in a lot of cordless loudspeaker specification sheets. This technique was designed with the knowledge that human hearing perceives noise at different frequencies differently. Human hearing is most responsive to signals around 1 kHz. On the other hand, signals below 50 Hz and above 13 kHz are hardly heard. Consequently an A-weighting filter will amplify the noise floor for frequencies that are easily heard and suppress the noise floor at frequencies that are hardly heard. The majority of wireless speaker are going to have a higher A-weighted signal-to-noise ratio than the un-weighted ratio.
Once you have narrowed down your search by taking a look at some key criteria, including the amount of output wattage, the dimensions of the speakers plus the price, you are going to still have quite a few products to choose from. Now it is time to look at a couple of the technical specs in more detail. An important parameter of wireless loudspeakers is the signal-to-noise ratio. To put it simply, the signal-to-noise ratio explains how much hum or hiss the loudspeakers are going to add to the music signal. This ratio is usually shown in decibel or "db" for short.
A method in order to perform a simple check of the noise performance of a set of wireless speakers is to short circuit the transmitter audio input and then to crank up the wireless loudspeaker to its utmost. Then listen to the loudspeaker. The static which you hear is produced by the cordless speaker itself. Make sure that the gain of each set of wireless loudspeakers is couple to the same amount. Otherwise you will not be able to objectively compare the level of static between several models. The general rule is: the lower the amount of noise that you hear the better the noise performance.
To help you compare the noise performance, cordless loudspeaker suppliers show the signal-to-noise ratio in their wireless speaker spec sheets. Simply put, the larger the signal-to-noise ratio, the lower the level of noise the cordless loudspeaker generates. Noise is produced due to several factors. One factor is that today's wireless speakers all make use of components such as transistors plus resistors. Those components will produce some amount of noise. Because the built-in power amp overall noise performance is mostly determined by the performance of components situated at the amplifier input, makers are going to try to choose low-noise elements whilst developing the amplifier input stage of their cordless speakers.
The cordless broadcast itself also causes static which is most noticable with products which use FM transmission at 900 MHz. FM transmitters are very prone to cordless interference which is why newer types typically use digital audio broadcast. The signal-to-noise ratio of digital transmitters is dependent mostly on the type of analog-to-digital converters and other parts which are utilized and also the resolution of the cordless protocol.
Many of modern cordless speaker use amps which are based on a digital switching topology. These amplifiers are named "class-D" or "class-T" amps. Switching amps incorporate a power stage which is always switched at a frequency of approximately 400 kHz. This switching frequency is also hiss which is part of the amplified signal. However, modern cordless loudspeakerspecs usually only consider the hiss between 20 Hz and 20 kHz.
Makers measure the signal-to-noise ratio by setting the built-in amplifier such that the full output swing can be realized and by inputting a test tone to the transmitter that is normally 60 dB underneath the full scale of the speaker amplifier. 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.
Another convention to express the signal-to-noise ratio utilizes more subjective terms. These terms are "dBA" or "A weighted". You will spot these terms in a lot of cordless loudspeaker specification sheets. This technique was designed with the knowledge that human hearing perceives noise at different frequencies differently. Human hearing is most responsive to signals around 1 kHz. On the other hand, signals below 50 Hz and above 13 kHz are hardly heard. Consequently an A-weighting filter will amplify the noise floor for frequencies that are easily heard and suppress the noise floor at frequencies that are hardly heard. The majority of wireless speaker are going to have a higher A-weighted signal-to-noise ratio than the un-weighted ratio.
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