To help you select an audio amp, I will describe the expression "signal-to-noise ratio" which is commonly utilized in order to depict the performance of audio amps. Whilst trying to find an amplifier, you firstly are going to check the price, wattage among other fundamental criteria. However, after this initial choice, you are going to still have quite a few products to choose from. Now you will concentrate more on a few of the technical specs, such as signal-to-noise ratio and harmonic distortion. The signal-to-noise ratio is a rather key specification and shows how much noise or hiss the amplifier makes.
Comparing the noise level of different amplifiers may be done fairly simply. Simply gather a few products which you want to compare and short circuit the inputs. Next put the amp volume to maximum and verify the amount of hiss by listening to the loudspeaker. The noise that you hear is generated by the amp itself. Next compare different amplifiers according to the following rule: the lower the level of noise, the higher the noise performance of the amplifier. Yet, keep in mind that you must set all amps to amplify by the same level to evaluate several amps.
Evaluating the noise level of several amps may be accomplished quite easily. Just get together a few versions that you want to evaluate and short circuit the inputs. Then set the amplifier gain to maximum and check the level of static by listening to the loudspeaker. The noise which you hear is produced by the amplifier itself. Make certain that the gain of the amplifiers is set to the same level. Otherwise you will not be able to objectively evaluate the amount of static between several amps. The general rule is: the lower the level of hiss that you hear the higher the noise performance. Whilst glancing at the amplifier spec sheet, you want to look for an amplifier with a large signal-to-noise ratio figure which suggests that the amp outputs a low level of noise. Noise is produced due to a number of factors. One factor is that modern amps all employ elements including transistors as well as resistors. Those components will generate some amount of noise. Generally the components that are situated at the input stage of an amp will contribute most to the overall hiss. Thus makers typically will pick low-noise components while developing the amplifier input stage.
Many of recent amplifiers are based on a digital switching architecture. They are named "class-D" or "class-T" amplifiers. Switching amps include a power stage that is constantly switched at a frequency of around 400 kHz. This switching frequency is also hiss that is part of the amplified signal. Nonetheless, latest amplifier specs generally only consider the hiss between 20 Hz and 20 kHz.
The majority of modern power amps are digital amplifiers, also referred to as "class-d amplifiers". Class-D amps make use of a switching stage that oscillates at a frequency in the range of 300 kHz to 1 MHz. As a result, the output signal of switching amps contain a rather large amount of switching noise. This noise component, though, is typically impossible to hear given that it is well above 20 kHz. Though, it can still contribute to loudspeaker distortion. Signal-to-noise ratio is typically only shown within the range of 20 Hz to 20 kHz. Consequently, a lowpass filter is used when measuring switching amplifiers to remove the switching noise. The most common technique for measuring the signal-to-noise ratio is to set the amplifier to a gain that enables the maximum output swing. Next a test signal is fed to the amp. The frequency of this tone is usually 1 kHz. The amplitude of this tone is 60 dB underneath the full scale signal. After that, only the noise between 20 Hz and 20 kHz is considered. The noise at other frequencies is removed by a filter. After that the level of the noise energy in relation to the full-scale output power is calculated and expressed in db.
Time and again you are going to find the expression "dBA" or "a-weighted" in your amp parameter sheet. A weighting is a method of showing the noise floor in a more subjective manner. This technique tries to evaluate in how far the amp noise is perceived by human hearing which is most sensitive to signals at frequencies at 1 kHz. As a result an A-weighting filter is going to magnify the noise floor for frequencies that are easily perceived and suppress the noise floor at frequencies which are hardly heard. The majority of amplifiers are going to have a larger A-weighted signal-to-noise ratio than the un-weighted ratio.
Comparing the noise level of different amplifiers may be done fairly simply. Simply gather a few products which you want to compare and short circuit the inputs. Next put the amp volume to maximum and verify the amount of hiss by listening to the loudspeaker. The noise that you hear is generated by the amp itself. Next compare different amplifiers according to the following rule: the lower the level of noise, the higher the noise performance of the amplifier. Yet, keep in mind that you must set all amps to amplify by the same level to evaluate several amps.
Evaluating the noise level of several amps may be accomplished quite easily. Just get together a few versions that you want to evaluate and short circuit the inputs. Then set the amplifier gain to maximum and check the level of static by listening to the loudspeaker. The noise which you hear is produced by the amplifier itself. Make certain that the gain of the amplifiers is set to the same level. Otherwise you will not be able to objectively evaluate the amount of static between several amps. The general rule is: the lower the level of hiss that you hear the higher the noise performance. Whilst glancing at the amplifier spec sheet, you want to look for an amplifier with a large signal-to-noise ratio figure which suggests that the amp outputs a low level of noise. Noise is produced due to a number of factors. One factor is that modern amps all employ elements including transistors as well as resistors. Those components will generate some amount of noise. Generally the components that are situated at the input stage of an amp will contribute most to the overall hiss. Thus makers typically will pick low-noise components while developing the amplifier input stage.
Many of recent amplifiers are based on a digital switching architecture. They are named "class-D" or "class-T" amplifiers. Switching amps include a power stage that is constantly switched at a frequency of around 400 kHz. This switching frequency is also hiss that is part of the amplified signal. Nonetheless, latest amplifier specs generally only consider the hiss between 20 Hz and 20 kHz.
The majority of modern power amps are digital amplifiers, also referred to as "class-d amplifiers". Class-D amps make use of a switching stage that oscillates at a frequency in the range of 300 kHz to 1 MHz. As a result, the output signal of switching amps contain a rather large amount of switching noise. This noise component, though, is typically impossible to hear given that it is well above 20 kHz. Though, it can still contribute to loudspeaker distortion. Signal-to-noise ratio is typically only shown within the range of 20 Hz to 20 kHz. Consequently, a lowpass filter is used when measuring switching amplifiers to remove the switching noise. The most common technique for measuring the signal-to-noise ratio is to set the amplifier to a gain that enables the maximum output swing. Next a test signal is fed to the amp. The frequency of this tone is usually 1 kHz. The amplitude of this tone is 60 dB underneath the full scale signal. After that, only the noise between 20 Hz and 20 kHz is considered. The noise at other frequencies is removed by a filter. After that the level of the noise energy in relation to the full-scale output power is calculated and expressed in db.
Time and again you are going to find the expression "dBA" or "a-weighted" in your amp parameter sheet. A weighting is a method of showing the noise floor in a more subjective manner. This technique tries to evaluate in how far the amp noise is perceived by human hearing which is most sensitive to signals at frequencies at 1 kHz. As a result an A-weighting filter is going to magnify the noise floor for frequencies that are easily perceived and suppress the noise floor at frequencies which are hardly heard. The majority of amplifiers are going to have a larger A-weighted signal-to-noise ratio than the un-weighted ratio.
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