To help you select a couple of cordless loudspeakers, I am going to explain the expression "signal-to-noise ratio" which is usually used in order to describe the performance of cordless speakers.
Once you have selected a range of cordless speakers, it's time to investigate some of the specifications in more detail to help you narrow down your search to one product. One important parameter of cordless loudspeakers is the signal-to-noise ratio. To put it simply, the signal-to-noise ratio describes how much hum or hiss the speakers are going to add to the music signal. This ratio is generally shown in decibel or "db" for short.
One way in order to perform a straightforward assessment of the noise performance of a pair 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 speaker. The noise which you hear is produced by the wireless loudspeaker itself. Make sure that the volume of each pair of cordless speakers is couple to the same amount. Otherwise you will not be able to objectively evaluate the level of noise between different models. The general rule is: the smaller the level of hiss that you hear the higher the noise performance.
If you favor a set of wireless speakers with a small amount of hissing, you may look at the signal-to-noise ratio number of the data sheet. The majority of manufacturers will display this number. wireless speakers with a high signal-to-noise ratio will output a small level of noise. Noise is produced due to several reasons. One factor is that today's cordless speakers all utilize components including transistors as well as resistors. Those elements will make some amount of noise. Because the built-in power amplifier overall noise performance is mostly determined by the performance of components located at the amplifier input, producers are going to try to pick low-noise components when developing the amp input stage of their wireless loudspeakers.
The cordless transmission itself also will cause static that is most noticable with models which utilize FM transmission at 900 MHz. The amount of hiss is also dependent upon the level of cordless interference from other transmitters. Modern types will generally use digital music transmission at 2.4 GHz or 5.8 GHz. The signal-to-noise ratio of digital transmitters depends by and large on the type of analog-to-digital converters and other parts which are utilized and also the resolution of the wireless protocol.
Many of modern cordless speaker use amps which are based on a digital switching topology. These amplifiers are called "class-D" or "class-T" amplifiers. Switching amplifiers include a power stage that is constantly switched at a frequency of approximately 400 kHz. This switching frequency is also hiss that is part of the amplified signal. On the other hand, latest cordless loudspeakerspecs usually only consider the hiss between 20 Hz and 20 kHz.
The signal-to-noise ratio is measured by feeding a 1 kHz test tone 60 dB underneath the full scale and measuring the noise floor of the signal generated by the built-in amplifier. The volume of the wireless speaker is pair such that the full output power of the built-in amp can be achieved. Subsequently the noise-floor energy is measured in the frequency range between 20 Hz and 20 kHz and compared with the full scale signal energy.
Often the signal-to-noise ratio is shown in a more subjective manner as "dbA" or "A weighted". This method attempts to examine in how far the wireless speaker noise is perceived by human hearing which is most perceptive to signals at frequencies at 1 kHz. For that reason an A-weighting filter will magnify the noise floor for frequencies that are easily perceived and suppress the noise floor at frequencies that are hardly heard. Most cordless loudspeaker will have a larger A-weighted signal-to-noise ratio than the un-weighted ratio.
Once you have selected a range of cordless speakers, it's time to investigate some of the specifications in more detail to help you narrow down your search to one product. One important parameter of cordless loudspeakers is the signal-to-noise ratio. To put it simply, the signal-to-noise ratio describes how much hum or hiss the speakers are going to add to the music signal. This ratio is generally shown in decibel or "db" for short.
One way in order to perform a straightforward assessment of the noise performance of a pair 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 speaker. The noise which you hear is produced by the wireless loudspeaker itself. Make sure that the volume of each pair of cordless speakers is couple to the same amount. Otherwise you will not be able to objectively evaluate the level of noise between different models. The general rule is: the smaller the level of hiss that you hear the higher the noise performance.
If you favor a set of wireless speakers with a small amount of hissing, you may look at the signal-to-noise ratio number of the data sheet. The majority of manufacturers will display this number. wireless speakers with a high signal-to-noise ratio will output a small level of noise. Noise is produced due to several reasons. One factor is that today's cordless speakers all utilize components including transistors as well as resistors. Those elements will make some amount of noise. Because the built-in power amplifier overall noise performance is mostly determined by the performance of components located at the amplifier input, producers are going to try to pick low-noise components when developing the amp input stage of their wireless loudspeakers.
The cordless transmission itself also will cause static that is most noticable with models which utilize FM transmission at 900 MHz. The amount of hiss is also dependent upon the level of cordless interference from other transmitters. Modern types will generally use digital music transmission at 2.4 GHz or 5.8 GHz. The signal-to-noise ratio of digital transmitters depends by and large on the type of analog-to-digital converters and other parts which are utilized and also the resolution of the wireless protocol.
Many of modern cordless speaker use amps which are based on a digital switching topology. These amplifiers are called "class-D" or "class-T" amplifiers. Switching amplifiers include a power stage that is constantly switched at a frequency of approximately 400 kHz. This switching frequency is also hiss that is part of the amplified signal. On the other hand, latest cordless loudspeakerspecs usually only consider the hiss between 20 Hz and 20 kHz.
The signal-to-noise ratio is measured by feeding a 1 kHz test tone 60 dB underneath the full scale and measuring the noise floor of the signal generated by the built-in amplifier. The volume of the wireless speaker is pair such that the full output power of the built-in amp can be achieved. Subsequently the noise-floor energy is measured in the frequency range between 20 Hz and 20 kHz and compared with the full scale signal energy.
Often the signal-to-noise ratio is shown in a more subjective manner as "dbA" or "A weighted". This method attempts to examine in how far the wireless speaker noise is perceived by human hearing which is most perceptive to signals at frequencies at 1 kHz. For that reason an A-weighting filter will magnify the noise floor for frequencies that are easily perceived and suppress the noise floor at frequencies that are hardly heard. Most cordless loudspeaker will have a larger A-weighted signal-to-noise ratio than the un-weighted ratio.
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