subject: Points To Know About Amplifier Power Efficiency [print this page] Let me take a look at the phrase "power efficiency" which tells you just how much music audio amplifiers waste so that you can choose an amp.
The less efficient your amp is, the more power is going to be wasted which results in many issues: Low-efficiency amplifiers are going to squander a certain amount of power as heat and are more costly to use in comparison with high-efficiency models because of the higher power consumption. Amplifiers that have small power efficiency typically have a number of heat sinks to help radiate the squandered power. These heat sinks use up a reasonable amount of space and make the amp bulky and heavy. Additionally, they add to the cost of the amplifier. Amplifiers that have low efficiency cannot be placed in small spaces or inside sealed enclosures since they need a good amount of circulation.
Amplifiers that have low efficiency need a larger power source to create the identical amount of audio power as high-efficiency types. Additionally, due to the large level of heat, there is going to be considerably higher thermal stress on the electric elements as well as interior materials that might result in reliability issues. In comparison, high-efficiency amplifiers can be produced small and lightweight.
While buying an amp, you will find the efficiency in the data sheet. This value is usually listed as a percentage. Class-A amps are among the least efficient and provide a efficiency of approximately 25% only. In comparison, switching amplifiers, also called "Class-D" amplifiers provide efficiencies up to 98%. Having an amp which has an efficiency of 90% for example shows that 10% of the energy that is used is squandered when 90% will be audio power.
What is less well-known about efficiency is the fact that this figure is not fixed. Actually it differs based on how much power the amplifier offers. Thus in some cases you'll find efficiency figures for different energy levels within the data sheet. Because each amplifier is going to require a certain amount of power, regardless of the level of energy the amplifier delivers to the loudspeakers, the amplifier efficiency is larger the more power the amp provides and is typically specified for the greatest power the amplifier can handle.
To figure out the efficiency, the audio energy that is consumed by a power resistor which is attached to the amplifier is divided by the total power the amplifier consumes while being fed a constant sine wave tone. Ordinarily a complete power report is plotted to display the dependence of the efficiency on the output power. This is why the output power is swept through various values. The power efficiency at every value is measured plus a efficiency graph created.
Switching-mode amps use a switching stage that leads to some amount of non-linear behavior. Thus Class-D amps generally have smaller music fidelity than analog Class-A amplifiers. Subsequently you are going to have to base your decision on whether you require small dimensions and minimal energy consumption or greatest audio fidelity. A few newer music amp models, such as Class-T amplifiers, can minimize audio distortion to amounts near to the ones from analog music amps and in addition can accomplish great signal-to-noise ratio. Selecting one of these kinds of amps will offer high power efficiency and at the same time high music fidelity.
