It is easy to be puzzled by the language which cordless loudspeaker suppliers utilize in order to express the performance of their products. I am going to clarify the meaning of one regularly used specification: "signal-to-noise ratio" to help you make an informed choice whilst purchasing a new a couple of cordless loudspeakers.
As soon as you have narrowed down your search by taking a look at several fundamental criteria, such as the amount of output wattage, the size of the speakers plus the cost, you will still have quite a few models to choose from. Now it is time to look at a few of the technical specs in more detail. The signal-to-noise ratio is a fairly vital spec and explains how much noise or hiss the wireless speaker produces.
Evaluating the noise level of different sets of wireless speakers can be accomplished quite easily. Just collect a couple of types which you wish to compare and short circuit the transmitter audio inputs. Afterward set the cordless loudspeaker volume to maximum and verify the amount of hiss by listening to the loudspeaker. The noise which you hear is created by the wireless loudspeaker itself. Make sure that the volume of each couple of wireless loudspeakers is pair to the same level. Otherwise you will not be able to objectively evaluate the amount of noise between several models. The general rule is: the lower the amount of noise that you hear the better the noise performance.
While glancing at the cordless loudspeaker spec sheet, you want to look for a set of cordless loudspeaker with a high signal-to-noise ratio figure which indicates that the cordless loudspeakers output a low amount of static. Noise is produced due to a number of reasons. One reason is that modern wireless speakers all employ elements like transistors and resistors. These elements are going to make some amount of noise. The overall noise is dependent on how much noise each component creates. However, the position of these components is also essential. Components that are part of the loudspeaker built-in amp input stage will in general contribute the majority of the noise.
One more cause of hiss is the wireless audio broadcast itself. Normally models which employ FM style broadcast at 900 MHz will have a rather large amount of hiss. The amount of hiss is also dependent upon the amount of wireless interference from other transmitters. Modern models are going to generally utilize digital music broadcast at 2.4 GHz or 5.8 GHz. The signal-to-noise ratio of digital transmitters depends by and large on the kind of analog-to-digital converters and other components which are utilized along with the resolution of the wireless protocol.
Many of latest cordless speaker use amplifiers which are based on a digital switching topology. These amplifiers are named "class-D" or "class-T" amplifiers. Switching amps incorporate a power stage which is continuously switched at a frequency of around 400 kHz. As a result, the output signal of cordless speaker switching amplifiers contain a moderately large amount of switching noise. This noise component, however, is typically impossible to hear as it is well above 20 kHz. Yet, it may still contribute to speaker distortion. Signal-to-noise ratio is generally only shown within the range of 20 Hz to 20 kHz. Consequently, a lowpass filter is used while measuring wireless loudspeaker amps in order to eliminate the switching noise.
The most popular technique for measuring the signal-to-noise ratio is to set the wireless loudspeaker to a gain which allows the maximum output swing. After that a test signal is input into the transmitter. The frequency of this tone is generally 1 kHz. The amplitude of this tone is 60 dB underneath the full scale signal. Next, the noise floor between 20 Hz and 20 kHz is measured and the ratio to the full-scale signal calculated. The noise signal at different frequencies is eliminated by a bandpass filter throughout this measurement.
A different convention to express the signal-to-noise ratio utilizes more subjective terms. These terms are "dBA" or "A weighted". You are going to discover these terms in many cordless loudspeaker parameter sheets. This method tries to examine in how far the wireless speaker noise is perceived by human hearing which is most sensitive 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 generally higher than the unweighted signal-to-noise ratio.
As soon as you have narrowed down your search by taking a look at several fundamental criteria, such as the amount of output wattage, the size of the speakers plus the cost, you will still have quite a few models to choose from. Now it is time to look at a few of the technical specs in more detail. The signal-to-noise ratio is a fairly vital spec and explains how much noise or hiss the wireless speaker produces.
Evaluating the noise level of different sets of wireless speakers can be accomplished quite easily. Just collect a couple of types which you wish to compare and short circuit the transmitter audio inputs. Afterward set the cordless loudspeaker volume to maximum and verify the amount of hiss by listening to the loudspeaker. The noise which you hear is created by the wireless loudspeaker itself. Make sure that the volume of each couple of wireless loudspeakers is pair to the same level. Otherwise you will not be able to objectively evaluate the amount of noise between several models. The general rule is: the lower the amount of noise that you hear the better the noise performance.
While glancing at the cordless loudspeaker spec sheet, you want to look for a set of cordless loudspeaker with a high signal-to-noise ratio figure which indicates that the cordless loudspeakers output a low amount of static. Noise is produced due to a number of reasons. One reason is that modern wireless speakers all employ elements like transistors and resistors. These elements are going to make some amount of noise. The overall noise is dependent on how much noise each component creates. However, the position of these components is also essential. Components that are part of the loudspeaker built-in amp input stage will in general contribute the majority of the noise.
One more cause of hiss is the wireless audio broadcast itself. Normally models which employ FM style broadcast at 900 MHz will have a rather large amount of hiss. The amount of hiss is also dependent upon the amount of wireless interference from other transmitters. Modern models are going to generally utilize digital music broadcast at 2.4 GHz or 5.8 GHz. The signal-to-noise ratio of digital transmitters depends by and large on the kind of analog-to-digital converters and other components which are utilized along with the resolution of the wireless protocol.
Many of latest cordless speaker use amplifiers which are based on a digital switching topology. These amplifiers are named "class-D" or "class-T" amplifiers. Switching amps incorporate a power stage which is continuously switched at a frequency of around 400 kHz. As a result, the output signal of cordless speaker switching amplifiers contain a moderately large amount of switching noise. This noise component, however, is typically impossible to hear as it is well above 20 kHz. Yet, it may still contribute to speaker distortion. Signal-to-noise ratio is generally only shown within the range of 20 Hz to 20 kHz. Consequently, a lowpass filter is used while measuring wireless loudspeaker amps in order to eliminate the switching noise.
The most popular technique for measuring the signal-to-noise ratio is to set the wireless loudspeaker to a gain which allows the maximum output swing. After that a test signal is input into the transmitter. The frequency of this tone is generally 1 kHz. The amplitude of this tone is 60 dB underneath the full scale signal. Next, the noise floor between 20 Hz and 20 kHz is measured and the ratio to the full-scale signal calculated. The noise signal at different frequencies is eliminated by a bandpass filter throughout this measurement.
A different convention to express the signal-to-noise ratio utilizes more subjective terms. These terms are "dBA" or "A weighted". You are going to discover these terms in many cordless loudspeaker parameter sheets. This method tries to examine in how far the wireless speaker noise is perceived by human hearing which is most sensitive 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 generally higher than the unweighted signal-to-noise ratio.
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