To help you choose a couple of cordless speakers, I will explain the expression "signal-to-noise ratio" which is frequently used to describe the performance of cordless speakers.
Once you have selected a number of wireless speakers, it's time to investigate a few of the specs in more detail to help you narrow down your search to one product. Each cordless speaker is going to generate a certain level of hiss and hum. The signal-to-noise ratio will help compute the level of static created by the loudspeaker.
You can perform a straightforward comparison of the cordless speaker hiss by short circuiting the transmitter input, setting the loudspeaker gain to maximum and listening to the speaker. The noise that you hear is produced by the wireless speaker itself. After that compare several sets of cordless loudspeakers according to the next rule: the lower the amount of static, the higher the noise performance of the wireless loudspeaker. Yet, keep in mind that you must put all sets of wireless speakers to amplify by the same level to evaluate different models.
If you favor a couple of wireless loudspeakers with a small amount of hissing, you can look at the signal-to-noise ratio number of the specification sheet. Many manufacturers will display this number. cordless loudspeakers with a large signal-to-noise ratio will output a low level of static. Noise is created due to a number of factors. One factor is that modern cordless loudspeakers all use components such as transistors along with resistors. These elements are going to make some amount of noise. Given that the built-in power amplifier overall noise performance is mostly determined by the performance of components situated at the amplifier input, manufacturers will try to select low-noise elements when designing the amp input stage of their cordless loudspeakers.
A further cause of noise is the wireless music transmission itself. Usually products which make use of FM style transmission at 900 MHz will have a comparatively large level of static. Other wireless transmitters will interfer with FM type transmitters and cause additional hiss. Therefore the signal-to-noise ratio of FM type wireless speakers changes depending on the distance of the loudspeakers from the transmitter in addition to the level of interference. To avoid these problems, modern transmitters employ digital music broadcast and typically transmit at 2.4 GHz or 5.8 GHz. This type of music transmission offers higher signal-to-noise ratio than analog type transmitters. The level of static depends on the resolution of the analog-to-digital converters as well as the quality of other components.
Most of latest cordless loudspeaker use amps which are based on a digital switching architecture. These amplifiers are called "class-D" or "class-T" amplifiers. Switching amps incorporate a power stage which is continuously switched at a frequency of around 400 kHz. This switching frequency is also noise that is part of the amplified signal. On the other hand, today's cordless loudspeakerspecs typically only consider the hiss between 20 Hz and 20 kHz.
The most widespread technique for measuring the signal-to-noise ratio is to pair the cordless speaker to a gain which allows the maximum output swing. After that a test tone is fed into the transmitter. The frequency of this signal 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 calculated and the ratio to the full-scale signal calculated. The noise signal at other frequencies is eliminated by a bandpass filter throughout this measurement.
Another convention in order to express the signal-to-noise ratio makes use of more subjective terms. These terms are "dBA" or "A weighted". You will spot these terms in the majority of wireless loudspeaker spec sheets. In other words, this method attempts to express how the noise is perceived by a human being. Human hearing is most perceptive to signals around 1 kHz whereas signals under 50 Hz and above 14 kHz are hardly noticed. The A-weighted signal-to-noise ratio is frequently larger than the unweighted ratio and is shown in the majority of wireless loudspeaker specification sheets.
Once you have selected a number of wireless speakers, it's time to investigate a few of the specs in more detail to help you narrow down your search to one product. Each cordless speaker is going to generate a certain level of hiss and hum. The signal-to-noise ratio will help compute the level of static created by the loudspeaker.
You can perform a straightforward comparison of the cordless speaker hiss by short circuiting the transmitter input, setting the loudspeaker gain to maximum and listening to the speaker. The noise that you hear is produced by the wireless speaker itself. After that compare several sets of cordless loudspeakers according to the next rule: the lower the amount of static, the higher the noise performance of the wireless loudspeaker. Yet, keep in mind that you must put all sets of wireless speakers to amplify by the same level to evaluate different models.
If you favor a couple of wireless loudspeakers with a small amount of hissing, you can look at the signal-to-noise ratio number of the specification sheet. Many manufacturers will display this number. cordless loudspeakers with a large signal-to-noise ratio will output a low level of static. Noise is created due to a number of factors. One factor is that modern cordless loudspeakers all use components such as transistors along with resistors. These elements are going to make some amount of noise. Given that the built-in power amplifier overall noise performance is mostly determined by the performance of components situated at the amplifier input, manufacturers will try to select low-noise elements when designing the amp input stage of their cordless loudspeakers.
A further cause of noise is the wireless music transmission itself. Usually products which make use of FM style transmission at 900 MHz will have a comparatively large level of static. Other wireless transmitters will interfer with FM type transmitters and cause additional hiss. Therefore the signal-to-noise ratio of FM type wireless speakers changes depending on the distance of the loudspeakers from the transmitter in addition to the level of interference. To avoid these problems, modern transmitters employ digital music broadcast and typically transmit at 2.4 GHz or 5.8 GHz. This type of music transmission offers higher signal-to-noise ratio than analog type transmitters. The level of static depends on the resolution of the analog-to-digital converters as well as the quality of other components.
Most of latest cordless loudspeaker use amps which are based on a digital switching architecture. These amplifiers are called "class-D" or "class-T" amplifiers. Switching amps incorporate a power stage which is continuously switched at a frequency of around 400 kHz. This switching frequency is also noise that is part of the amplified signal. On the other hand, today's cordless loudspeakerspecs typically only consider the hiss between 20 Hz and 20 kHz.
The most widespread technique for measuring the signal-to-noise ratio is to pair the cordless speaker to a gain which allows the maximum output swing. After that a test tone is fed into the transmitter. The frequency of this signal 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 calculated and the ratio to the full-scale signal calculated. The noise signal at other frequencies is eliminated by a bandpass filter throughout this measurement.
Another convention in order to express the signal-to-noise ratio makes use of more subjective terms. These terms are "dBA" or "A weighted". You will spot these terms in the majority of wireless loudspeaker spec sheets. In other words, this method attempts to express how the noise is perceived by a human being. Human hearing is most perceptive to signals around 1 kHz whereas signals under 50 Hz and above 14 kHz are hardly noticed. The A-weighted signal-to-noise ratio is frequently larger than the unweighted ratio and is shown in the majority of wireless loudspeaker specification sheets.
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