Are you looking to acquire a new a set of cordless speakers for your home? You may be dazzled by the amount of choices you have. In order to make an informed selection, it is best to familiarize yourself with frequent terms. One of these specifications is referred to as "signal-to-noise ratio" and is not often understood. I will help explain the meaning of this term.
When you have narrowed down your search by glancing at some basic criteria, including the amount of output power, the dimensions of the speakers as well as the cost, you will still have quite a few models to choose from. Now it is time to take a look at some of the technical specs in more detail. Every cordless loudspeaker is going to create a certain amount of hiss as well as hum. The signal-to-noise ratio will help calculate the amount of hiss generated by the speaker.
You can perform a simple comparison of the wireless speaker noise by short circuiting the transmitter input, setting the speaker volume to maximum and listening to the loudspeaker. Generally you will hear two components. The first is hissing. In addition, you will often hear a hum at 50 or 60 Hz. Both of these are components which are produced by the cordless speaker itself. Make certain that the volume of each set of cordless loudspeakers is pair to the same level. Otherwise you will not be able to objectively compare the amount of static between several models. The general rule is: the smaller the amount of static that you hear the better the noise performance.
To help you evaluate the noise performance, cordless loudspeaker manufacturers publish the signal-to-noise ratio in their cordless speaker specification sheets. Simply put, the larger the signal-to-noise ratio, the lower the amount of noise the wireless loudspeaker produces. One of the reasons why wireless loudspeakers generate noise is the fact that they use components like transistors as well as resistors which by nature create noise. Since the built-in power amplifier overall noise performance is mostly determined by the performance of elements located at the amplifier input, producers are going to attempt to select low-noise elements while designing the amplifier input stage of their wireless loudspeakers.
Static is also created by the cordless transmission. Different types of transmitters are available which operate at different frequencies. The most inexpensive type of transmitters uses FM transmission and commonly broadcasts at 900 MHz. Other cordless transmitters are going to interfer with FM type transmitters and cause additional static. Consequently the signal-to-noise ratio of FM type cordless loudspeakers changes depending on the distance of the loudspeakers from the transmitter plus the amount of interference. To steer clear of these problems, modern transmitters employ digital audio transmission and usually broadcast at 2.4 GHz or 5.8 GHz. This kind of audio transmission offers higher signal-to-noise ratio than analog style transmitters. The level of hiss is dependent on the resolution of the analog-to-digital converters as well as the quality of other components.
A lot of latest wireless speakers have built-in power amplifiers that include a power switching stage which switches at a frequency around 500 kHz. Because of this, the output signal of wireless speaker switching amplifiers exhibit a fairly large level of switching noise. This noise component, though, is generally inaudible as it is well above 20 kHz. On the other hand, it can still contribute to loudspeaker distortion. Signal-to-noise ratio is usually only shown within the range of 20 Hz to 20 kHz. Thus, a lowpass filter is utilized when measuring cordless speaker amps to eliminate the switching noise.
The signal-to-noise ratio is measured by inputting 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 amplification of the wireless speaker is pair such that the full output wattage of the built-in amp can be achieved. After that, the noise floor between 20 Hz and 20 kHz is calculated and the ratio to the full-scale signal calculated. The noise signal at other frequencies is eliminated via a bandpass filter throughout this measurement.
Another convention to state the signal-to-noise ratio uses more subjective terms. These terms are "dBA" or "A weighted". You will discover these terms in the majority of cordless speaker specification sheets. This technique was developed with the knowledge that human hearing perceives noise at different frequencies differently. Human hearing is most responsive to signals around 1 kHz. However, signals below 50 Hz and higher than 13 kHz are barely heard. An A-weighted signal-to-noise ratio weighs the noise floor in accordance to the human hearing and is generally higher than the unweighted signal-to-noise ratio.
When you have narrowed down your search by glancing at some basic criteria, including the amount of output power, the dimensions of the speakers as well as the cost, you will still have quite a few models to choose from. Now it is time to take a look at some of the technical specs in more detail. Every cordless loudspeaker is going to create a certain amount of hiss as well as hum. The signal-to-noise ratio will help calculate the amount of hiss generated by the speaker.
You can perform a simple comparison of the wireless speaker noise by short circuiting the transmitter input, setting the speaker volume to maximum and listening to the loudspeaker. Generally you will hear two components. The first is hissing. In addition, you will often hear a hum at 50 or 60 Hz. Both of these are components which are produced by the cordless speaker itself. Make certain that the volume of each set of cordless loudspeakers is pair to the same level. Otherwise you will not be able to objectively compare the amount of static between several models. The general rule is: the smaller the amount of static that you hear the better the noise performance.
To help you evaluate the noise performance, cordless loudspeaker manufacturers publish the signal-to-noise ratio in their cordless speaker specification sheets. Simply put, the larger the signal-to-noise ratio, the lower the amount of noise the wireless loudspeaker produces. One of the reasons why wireless loudspeakers generate noise is the fact that they use components like transistors as well as resistors which by nature create noise. Since the built-in power amplifier overall noise performance is mostly determined by the performance of elements located at the amplifier input, producers are going to attempt to select low-noise elements while designing the amplifier input stage of their wireless loudspeakers.
Static is also created by the cordless transmission. Different types of transmitters are available which operate at different frequencies. The most inexpensive type of transmitters uses FM transmission and commonly broadcasts at 900 MHz. Other cordless transmitters are going to interfer with FM type transmitters and cause additional static. Consequently the signal-to-noise ratio of FM type cordless loudspeakers changes depending on the distance of the loudspeakers from the transmitter plus the amount of interference. To steer clear of these problems, modern transmitters employ digital audio transmission and usually broadcast at 2.4 GHz or 5.8 GHz. This kind of audio transmission offers higher signal-to-noise ratio than analog style transmitters. The level of hiss is dependent on the resolution of the analog-to-digital converters as well as the quality of other components.
A lot of latest wireless speakers have built-in power amplifiers that include a power switching stage which switches at a frequency around 500 kHz. Because of this, the output signal of wireless speaker switching amplifiers exhibit a fairly large level of switching noise. This noise component, though, is generally inaudible as it is well above 20 kHz. On the other hand, it can still contribute to loudspeaker distortion. Signal-to-noise ratio is usually only shown within the range of 20 Hz to 20 kHz. Thus, a lowpass filter is utilized when measuring cordless speaker amps to eliminate the switching noise.
The signal-to-noise ratio is measured by inputting 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 amplification of the wireless speaker is pair such that the full output wattage of the built-in amp can be achieved. After that, the noise floor between 20 Hz and 20 kHz is calculated and the ratio to the full-scale signal calculated. The noise signal at other frequencies is eliminated via a bandpass filter throughout this measurement.
Another convention to state the signal-to-noise ratio uses more subjective terms. These terms are "dBA" or "A weighted". You will discover these terms in the majority of cordless speaker specification sheets. This technique was developed with the knowledge that human hearing perceives noise at different frequencies differently. Human hearing is most responsive to signals around 1 kHz. However, signals below 50 Hz and higher than 13 kHz are barely heard. An A-weighted signal-to-noise ratio weighs the noise floor in accordance to the human hearing and is generally higher than the unweighted signal-to-noise ratio.
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