To help you select a set of wireless loudspeakers, I am going to clarify the expression "signal-to-noise ratio" that is regularly used to depict the performance of wireless loudspeakers.
Whilst searching for a set of cordless speakers, you first are going to check the cost, power amongst other fundamental criteria. Nonetheless, after this initial selection, you will still have quite a few models to choose from. Now you are going to concentrate more on some of the technical specifications, including signal-to-noise ratio in addition to harmonic distortion. Each wireless loudspeaker will create a certain level of hiss and hum. The signal-to-noise ratio will help quantify the amount of noise created by the loudspeaker.
One method in order to do a simple check of the noise performance of a set of cordless loudspeakers is to short circuit the transmitter audio input and then to crank up the wireless loudspeaker to its maximum. Subsequently listen to the loudspeaker. The noise that you hear is produced by the wireless loudspeaker itself. Make certain that the gain of each set of cordless loudspeakers is set to the same amount. Otherwise you will not be able to objectively compare the amount of hiss between different models. The general rule is: the smaller the amount of hiss which you hear the higher the noise performance.
In order to help you compare the noise performance, cordless speaker manufacturers publish the signal-to-noise ratio in their cordless speaker spec sheets. Simply put, the higher the signal-to-noise ratio, the smaller the level of noise the cordless loudspeaker produces. One of the reasons why cordless speakers generate noise is the fact that they use components including transistors and resistors that by nature create noise. As the built-in power amplifier overall noise performance is mostly determined by the performance of components situated at the amp input, producers are going to try to choose low-noise elements while developing the amplifier input stage of their wireless speakers.
Noise is also caused by the cordless transmission. Different kinds of transmitters are available which work at different frequencies. The most inexpensive type of transmitters makes use of FM transmission and typically broadcasts at 900 MHz. FM transmitters are quite prone to wireless interference which is why newer models commonly employ digital music broadcast. The signal-to-noise ratio of digital transmitters depends mostly on the kind of analog-to-digital converters and other components which are utilized and also the resolution of the cordless protocol.
Most of modern wireless loudspeaker use amplifiers which are based on a digital switching architecture. These amplifiers are referred to as "class-D" or "class-T" amplifiers. Switching amps include a power stage that is always switched at a frequency of approximately 400 kHz. This switching noise can result in a certain amount of speaker distortion yet is typically not included in the signal-to-noise ratio which merely considers noise between 20 Hz and 20 kHz.
The most widespread method for measuring the signal-to-noise ratio is to pair the wireless speaker to a gain which allows the maximum output swing. Then a test signal is input into the transmitter. The frequency of this signal is typically 1 kHz. The amplitude of this signal is 60 dB below the full scale signal. Subsequently, only the noise in the range of 20 Hz and 20 kHz is considered. The noise at different frequencies is eliminated through a filter. After that the amount of the noise energy in relation to the full-scale output wattage is calculated and shown in decibel.
Often you are going to discover the expression "dBA" or "a-weighted" in your cordless speaker parameter sheet. A weighting is a method of expressing 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 under 50 Hz and above 13 kHz are barely noticed. Thus an A-weighting filter is going to magnify the noise floor for frequencies which are easily heard and suppress the noise floor at frequencies which are hardly perceived. Most wireless speaker will show a larger A-weighted signal-to-noise ratio than the un-weighted ratio.
Whilst searching for a set of cordless speakers, you first are going to check the cost, power amongst other fundamental criteria. Nonetheless, after this initial selection, you will still have quite a few models to choose from. Now you are going to concentrate more on some of the technical specifications, including signal-to-noise ratio in addition to harmonic distortion. Each wireless loudspeaker will create a certain level of hiss and hum. The signal-to-noise ratio will help quantify the amount of noise created by the loudspeaker.
One method in order to do a simple check of the noise performance of a set of cordless loudspeakers is to short circuit the transmitter audio input and then to crank up the wireless loudspeaker to its maximum. Subsequently listen to the loudspeaker. The noise that you hear is produced by the wireless loudspeaker itself. Make certain that the gain of each set of cordless loudspeakers is set to the same amount. Otherwise you will not be able to objectively compare the amount of hiss between different models. The general rule is: the smaller the amount of hiss which you hear the higher the noise performance.
In order to help you compare the noise performance, cordless speaker manufacturers publish the signal-to-noise ratio in their cordless speaker spec sheets. Simply put, the higher the signal-to-noise ratio, the smaller the level of noise the cordless loudspeaker produces. One of the reasons why cordless speakers generate noise is the fact that they use components including transistors and resistors that by nature create noise. As the built-in power amplifier overall noise performance is mostly determined by the performance of components situated at the amp input, producers are going to try to choose low-noise elements while developing the amplifier input stage of their wireless speakers.
Noise is also caused by the cordless transmission. Different kinds of transmitters are available which work at different frequencies. The most inexpensive type of transmitters makes use of FM transmission and typically broadcasts at 900 MHz. FM transmitters are quite prone to wireless interference which is why newer models commonly employ digital music broadcast. The signal-to-noise ratio of digital transmitters depends mostly on the kind of analog-to-digital converters and other components which are utilized and also the resolution of the cordless protocol.
Most of modern wireless loudspeaker use amplifiers which are based on a digital switching architecture. These amplifiers are referred to as "class-D" or "class-T" amplifiers. Switching amps include a power stage that is always switched at a frequency of approximately 400 kHz. This switching noise can result in a certain amount of speaker distortion yet is typically not included in the signal-to-noise ratio which merely considers noise between 20 Hz and 20 kHz.
The most widespread method for measuring the signal-to-noise ratio is to pair the wireless speaker to a gain which allows the maximum output swing. Then a test signal is input into the transmitter. The frequency of this signal is typically 1 kHz. The amplitude of this signal is 60 dB below the full scale signal. Subsequently, only the noise in the range of 20 Hz and 20 kHz is considered. The noise at different frequencies is eliminated through a filter. After that the amount of the noise energy in relation to the full-scale output wattage is calculated and shown in decibel.
Often you are going to discover the expression "dBA" or "a-weighted" in your cordless speaker parameter sheet. A weighting is a method of expressing 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 under 50 Hz and above 13 kHz are barely noticed. Thus an A-weighting filter is going to magnify the noise floor for frequencies which are easily heard and suppress the noise floor at frequencies which are hardly perceived. Most wireless speaker will show a larger A-weighted signal-to-noise ratio than the un-weighted ratio.
No comments:
Post a Comment