To help you pick a couple of wireless loudspeakers, I am going to explain the term "signal-to-noise ratio" that is regularly used in order to express the performance of wireless loudspeakers.
As soon as you have chosen a number of cordless speakers, it is time to explore several of the specifications in more detail in order to help you narrow down your search to one product. The signal-to-noise ratio is a fairly essential specification and shows how much noise or hiss the wireless loudspeaker makes.
Evaluating the noise level of several sets of wireless loudspeakers may be done quite simply. Simply get together a few types that you wish to compare and short circuit the transmitter audio inputs. Afterward set the wireless speaker gain to maximum and verify the amount of static by listening to the loudspeaker. The hiss that you hear is generated by the wireless speaker itself. Be certain that the volume of each pair of wireless speakers is pair to the same level. Otherwise you will not be able to objectively evaluate the level of hiss between different models. The general rule is: the smaller the level of noise which you hear the higher the noise performance.
When looking at the wireless speaker spec sheet, you want to look for a couple of cordless speaker with a large signal-to-noise ratio number which suggests that the wireless loudspeakers output a small level of hiss. Noise is generated due to several factors. One reason is that today's cordless speakers all utilize elements such as transistors along with resistors. These components are going to produce some amount of noise. The overall noise is dependent on how much hiss every element produces. However, the location of these elements is also essential. Elements that are part of the loudspeaker built-in amplifier input stage are going to normally contribute the majority of the noise.
The wireless broadcast itself also creates static which is most noticable with models which make use of FM transmission at 900 MHz. Other cordless transmitters are going to interfer with FM type transmitters and bring about further static. Consequently the signal-to-noise ratio of FM style cordless loudspeakers varies depending on the distance of the speakers from the transmitter plus the amount of interference. To avoid these problems, modern transmitters make use of digital audio broadcast and usually broadcast at 2.4 GHz or 5.8 GHz. This style of audio broadcast provides better signal-to-noise ratio than analog style transmitters. The level of hiss is dependent on the resolution of the analog-to-digital converters along with the quality of other parts.
The majority of today's wireless loudspeakers use power amps which are digital, also known as "class-d amplifiers". Class-D amplifiers make use of a switching stage that oscillates at a frequency in the range of 300 kHz to 1 MHz. Consequently, the output signal of cordless speaker switching amps contain a rather large amount of switching noise. This noise component, though, is usually impossible to hear because it is well above 20 kHz. Though, it may still contribute to loudspeaker distortion. Signal-to-noise ratio is typically only shown within the range of 20 Hz to 20 kHz. Therefore, a lowpass filter is utilized while measuring wireless speaker amplifiers in order to remove the switching noise.
The most widespread method for measuring the signal-to-noise ratio is to pair the cordless loudspeaker to a gain which permits the maximum output swing. Then a test tone is input into the transmitter. The frequency of this tone is usually 1 kHz. The amplitude of this signal is 60 dB below the full scale signal. Next the noise-floor energy is measured in the frequency range between 20 Hz and 20 kHz and compared with the full scale signal energy.
A different convention in order to state the signal-to-noise ratio utilizes more subjective terms. These terms are "dBA" or "A weighted". You are going to discover these terms in most cordless loudspeaker spec sheets. This technique was designed with the knowledge that human hearing perceives noise at different frequencies differently. Human hearing is most responsive to signals around 1 kHz. Though, signals below 50 Hz and higher than 13 kHz are barely heard. The A-weighted signal-to-noise ratio is frequently higher than the unweighted ratio and is shown in most cordless loudspeaker spec sheets.
As soon as you have chosen a number of cordless speakers, it is time to explore several of the specifications in more detail in order to help you narrow down your search to one product. The signal-to-noise ratio is a fairly essential specification and shows how much noise or hiss the wireless loudspeaker makes.
Evaluating the noise level of several sets of wireless loudspeakers may be done quite simply. Simply get together a few types that you wish to compare and short circuit the transmitter audio inputs. Afterward set the wireless speaker gain to maximum and verify the amount of static by listening to the loudspeaker. The hiss that you hear is generated by the wireless speaker itself. Be certain that the volume of each pair of wireless speakers is pair to the same level. Otherwise you will not be able to objectively evaluate the level of hiss between different models. The general rule is: the smaller the level of noise which you hear the higher the noise performance.
When looking at the wireless speaker spec sheet, you want to look for a couple of cordless speaker with a large signal-to-noise ratio number which suggests that the wireless loudspeakers output a small level of hiss. Noise is generated due to several factors. One reason is that today's cordless speakers all utilize elements such as transistors along with resistors. These components are going to produce some amount of noise. The overall noise is dependent on how much hiss every element produces. However, the location of these elements is also essential. Elements that are part of the loudspeaker built-in amplifier input stage are going to normally contribute the majority of the noise.
The wireless broadcast itself also creates static which is most noticable with models which make use of FM transmission at 900 MHz. Other cordless transmitters are going to interfer with FM type transmitters and bring about further static. Consequently the signal-to-noise ratio of FM style cordless loudspeakers varies depending on the distance of the speakers from the transmitter plus the amount of interference. To avoid these problems, modern transmitters make use of digital audio broadcast and usually broadcast at 2.4 GHz or 5.8 GHz. This style of audio broadcast provides better signal-to-noise ratio than analog style transmitters. The level of hiss is dependent on the resolution of the analog-to-digital converters along with the quality of other parts.
The majority of today's wireless loudspeakers use power amps which are digital, also known as "class-d amplifiers". Class-D amplifiers make use of a switching stage that oscillates at a frequency in the range of 300 kHz to 1 MHz. Consequently, the output signal of cordless speaker switching amps contain a rather large amount of switching noise. This noise component, though, is usually impossible to hear because it is well above 20 kHz. Though, it may still contribute to loudspeaker distortion. Signal-to-noise ratio is typically only shown within the range of 20 Hz to 20 kHz. Therefore, a lowpass filter is utilized while measuring wireless speaker amplifiers in order to remove the switching noise.
The most widespread method for measuring the signal-to-noise ratio is to pair the cordless loudspeaker to a gain which permits the maximum output swing. Then a test tone is input into the transmitter. The frequency of this tone is usually 1 kHz. The amplitude of this signal is 60 dB below the full scale signal. Next the noise-floor energy is measured in the frequency range between 20 Hz and 20 kHz and compared with the full scale signal energy.
A different convention in order to state the signal-to-noise ratio utilizes more subjective terms. These terms are "dBA" or "A weighted". You are going to discover these terms in most cordless loudspeaker spec sheets. This technique was designed with the knowledge that human hearing perceives noise at different frequencies differently. Human hearing is most responsive to signals around 1 kHz. Though, signals below 50 Hz and higher than 13 kHz are barely heard. The A-weighted signal-to-noise ratio is frequently higher than the unweighted ratio and is shown in most cordless loudspeaker spec sheets.
No comments:
Post a Comment