LovieZ0623999
Eltévedtél !!! Ez magyar szótár, nem levelező oldal:--karesznincs vita 2016. október 18., 14:20 (CEST)
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Thank you! --EGalvez (WMF) (talk) 2017. január 13., 23:26 (CET)
If you have spent a good deal of money on a pair of good-quality speakers, you wish to be confident that you get an audio amplifier that will provide outstanding audio quality while meeting your budget. I will present several tips about audio amplifier products to help you make the right purchasing decision.
It is difficult to select the best audio amp because of the large quantity of models. All of these types have different specs. They are built on different technologies and are available in all kinds of shapes and sizes. This makes it tricky to decide which type to select. You don’t have to be an expert. Just follow some plain rules and you should be satisfied with your amplifier.
The most evident parameter is the size of the amplifier. There are types that are as big as half your living room whilst several of the latest mini amplifier (related website) models are as tiny as a bar of soap. A large number of amplifiers are the size of a regular rack. This allows your amp to be stacked on top of your other audio equipment. The huge majority of modern audio amps are solid state amplifiers vs more conventional tube amps. Tube amplifiers have been prevalent a decade or so ago. Unfortunately, tube amplifiers have relatively high audio distortion which describes how much the audio signal is degraded by the amplifier.
An audio distortion of up to 10% is characteristic for tube amps while solid-state amps have less audio distortion depending on the specific technology. Several of the most popular technologies in the past have been "Class-A" and "Class-AB" technologies. These technologies use different arrangements to amplify the sound. Amplifiers based on any of these technologies are also known as "analog amplifiers". While amplifiers employing these technologies normally have low audio distortion, power efficiency is merely 10% to 30%. Power efficiency describes how much of the electrical power is used to amplify the audio versus being wasted as heat. Amplifiers with low power efficiency will require fairly large heat sinks since most of the power is radiated. Another technology is named "Class-D". This technology offers much greater power efficiency than analog amplifiers, generally around 80 to 90%. "Class-D" amps are also named "digital amplifiers". Due to the switching output stage, digital amplifiers generally have larger harmonic distortion than analog amplifiers. On the other hand, a few of the newest models are able to lower distortion to 0.05% and less by employing a feedback mechanism. The amp should be able to offer enough output power to sufficiently drive your speakers which will depend not only on how much power your loudspeakers can handle but also on the size of your listening environment. There are two values for speaker power handling: peak and average power handling. The peak value indicates how much power the speaker can tolerate for short periods of time. The average value on the other hand denotes how much power the speaker can tolerate constantly without damage.
In a small listening area, you might not require to drive your loudspeakers to their rated value. 20 to 40 Watts of power will most likely be enough. Speakers however differ in their impedance and sensitivity. As a rule of thumb speakers with low impedance offer higher sensitivity. High-sensitivity speakers are simpler to drive to high volume than low-sensitivity loudspeakers. Check your amplifier manual to ensure that your amp can drive your speaker impedance.
Lastly, be certain that your amp introduces little noise and has a broad enough frequency response. High-quality amps will have a signal-to-noise ratio of no less than 100 dB and a frequency response of no less than 20 Hz to 20 kHz.karesznincs vita 2017. február 28., 16:27 (CET)
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