It is easy to be puzzled by the terminology that cordless speaker suppliers use to depict the performance of their models. I am going to explain the meaning of a usually used parameter: "signal-to-noise ratio" in order to help you make an informed choice when purchasing a brand new a couple of cordless loudspeakers.
As soon as you have selected a range of wireless loudspeakers, it is time to explore a few of the specifications in more detail to help you narrow down your search to one model. The signal-to-noise ratio is a rather vital spec and describes how much noise or hiss the cordless loudspeaker produces.
A method to accomplish a straightforward test of the noise performance of a pair of wireless speakers is to short circuit the transmitter audio input and then to crank up the cordless loudspeaker to its maximum. Then listen to the speaker. You will hear some amount of hissing and/or hum coming from the loudspeaker. This noise is created by the wireless speaker itself. Next compare several sets of wireless speakers according to the following rule: the smaller the amount of noise, the better the noise performance of the cordless loudspeaker. However, bear in mind that you have to set all sets of cordless loudspeakers to amplify by the same level in order to compare different models.
If you favor a couple of cordless loudspeakers with a small amount of hissing, you can look at the signal-to-noise ratio number of the spec sheet. Most producers will publish this figure. cordless loudspeakers with a high signal-to-noise ratio are going to output a low level of noise. There are numerous reasons why wireless speakers will add some form of noise or other unwanted signal. Transistors and resistors which are part of each modern wireless speaker by nature make noise. As the built-in power amp overall noise performance is mostly determined by the performance of elements situated at the amp input, suppliers will attempt to pick low-noise parts when developing the amplifier input stage of their wireless loudspeakers.
Noise is also caused by the wireless broadcast. Different styles of transmitters are available which operate at different frequencies. The cheapest kind of transmitters employs FM transmission and generally broadcasts at 900 MHz. Other wireless transmitters are going to interfer with FM type transmitters and cause additional noise. Therefore the signal-to-noise ratio of FM style wireless speakers changes depending on the distance of the speakers from the transmitter in addition to the level of interference. To avoid these problems, modern transmitters employ digital audio broadcast and generally transmit at 2.4 GHz or 5.8 GHz. This kind of audio transmission provides larger signal-to-noise ratio than analog type transmitters. The amount of hiss is dependent on the resolution of the analog-to-digital converters and also the quality of other components.
The majority of today's cordless loudspeakers use power amplifiers which are digital, also called "class-d amps". Class-D amps make use of a switching stage which oscillates at a frequency in the range of 300 kHz to 1 MHz. This switching noise can cause a certain amount of speaker distortion yet is usually not included in the signal-to-noise ratio which merely considers noise between 20 Hz and 20 kHz.
Producers measure the signal-to-noise ratio by setting the built-in amp such that the full output swing can be achieved and by inputting a test signal to the transmitter which is typically 60 dB underneath the full scale of the speaker amplifier. Then, the noise floor between 20 Hz and 20 kHz is calculated and the ratio to the full-scale signal computed. The noise signal at different frequencies is removed through a bandpass filter throughout this measurement.
Time and again you will find the term "dBA" or "a-weighted" in your wireless loudspeaker specification sheet. A weighting is a technique of showing the noise floor in a more subjective fashion. This method tries to examine in how far the cordless speaker noise is perceived by human hearing which is most perceptive to signals at frequencies at 1 kHz. An A-weighted signal-to-noise ratio weighs the noise floor according to the human hearing and is typically larger than the unweighted signal-to-noise ratio.
As soon as you have selected a range of wireless loudspeakers, it is time to explore a few of the specifications in more detail to help you narrow down your search to one model. The signal-to-noise ratio is a rather vital spec and describes how much noise or hiss the cordless loudspeaker produces.
A method to accomplish a straightforward test of the noise performance of a pair of wireless speakers is to short circuit the transmitter audio input and then to crank up the cordless loudspeaker to its maximum. Then listen to the speaker. You will hear some amount of hissing and/or hum coming from the loudspeaker. This noise is created by the wireless speaker itself. Next compare several sets of wireless speakers according to the following rule: the smaller the amount of noise, the better the noise performance of the cordless loudspeaker. However, bear in mind that you have to set all sets of cordless loudspeakers to amplify by the same level in order to compare different models.
If you favor a couple of cordless loudspeakers with a small amount of hissing, you can look at the signal-to-noise ratio number of the spec sheet. Most producers will publish this figure. cordless loudspeakers with a high signal-to-noise ratio are going to output a low level of noise. There are numerous reasons why wireless speakers will add some form of noise or other unwanted signal. Transistors and resistors which are part of each modern wireless speaker by nature make noise. As the built-in power amp overall noise performance is mostly determined by the performance of elements situated at the amp input, suppliers will attempt to pick low-noise parts when developing the amplifier input stage of their wireless loudspeakers.
Noise is also caused by the wireless broadcast. Different styles of transmitters are available which operate at different frequencies. The cheapest kind of transmitters employs FM transmission and generally broadcasts at 900 MHz. Other wireless transmitters are going to interfer with FM type transmitters and cause additional noise. Therefore the signal-to-noise ratio of FM style wireless speakers changes depending on the distance of the speakers from the transmitter in addition to the level of interference. To avoid these problems, modern transmitters employ digital audio broadcast and generally transmit at 2.4 GHz or 5.8 GHz. This kind of audio transmission provides larger signal-to-noise ratio than analog type transmitters. The amount of hiss is dependent on the resolution of the analog-to-digital converters and also the quality of other components.
The majority of today's cordless loudspeakers use power amplifiers which are digital, also called "class-d amps". Class-D amps make use of a switching stage which oscillates at a frequency in the range of 300 kHz to 1 MHz. This switching noise can cause a certain amount of speaker distortion yet is usually not included in the signal-to-noise ratio which merely considers noise between 20 Hz and 20 kHz.
Producers measure the signal-to-noise ratio by setting the built-in amp such that the full output swing can be achieved and by inputting a test signal to the transmitter which is typically 60 dB underneath the full scale of the speaker amplifier. Then, the noise floor between 20 Hz and 20 kHz is calculated and the ratio to the full-scale signal computed. The noise signal at different frequencies is removed through a bandpass filter throughout this measurement.
Time and again you will find the term "dBA" or "a-weighted" in your wireless loudspeaker specification sheet. A weighting is a technique of showing the noise floor in a more subjective fashion. This method tries to examine in how far the cordless speaker noise is perceived by human hearing which is most perceptive to signals at frequencies at 1 kHz. An A-weighted signal-to-noise ratio weighs the noise floor according to the human hearing and is typically larger than the unweighted signal-to-noise ratio.
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