Total system power
Encyclopedia
Total system power is a term often used in audio electronics
to rate the power of an audio system. Total system power refers to the total power consumption
of the unit, rather than the power handling of the speakers
or the power output of the amplifier
. This can be viewed as a somewhat deceptive marketing
ploy, as the total power consumption of the unit will of course be greater than any of its other power ratings, except for, perhaps, the peak power of the amplifier, which is essentially an exaggerated value anyway. Shelf stereo
s and surround sound
receivers are often rated using total system power.
One way to use total system power to get a more accurate estimate of power is to consider the amplifier class which would give an educated guess of the power output by considering the efficiency of the class. For example, class AB amplifiers are around 25 or 50% efficiency while Class D amps are much higher; around 80% or more efficiency. A very exceptional efficiency for a specific Class D amp, the ROHM
BD5421efs, operates at 90% efficiency.
In some cases, an audio device may be measured by the total system power of all its loudspeakers by adding all their peak power ratings. Many home theater in a box
systems are rated this way. Often low-end home theater systems' power ratings are taken at a high level of harmonic distortion as well; as high as 10%, which would be painfully noticeable.
Audio engineering
An audio engineer, also called audio technician, audio technologist or sound technician, is a specialist in a skilled trade that deals with the use of machinery and equipment for the recording, mixing and reproduction of sounds. The field draws on many artistic and vocational areas, including...
to rate the power of an audio system. Total system power refers to the total power consumption
Energy consumption
Energy consumption is the consumption of energy or power. It is covered in the following articles and categories:* World energy consumption* Domestic energy consumption* Fuel efficiency in transportation* Electric energy consumption* Electricity generation...
of the unit, rather than the power handling of the speakers
Loudspeaker
A loudspeaker is an electroacoustic transducer that produces sound in response to an electrical audio signal input. Non-electrical loudspeakers were developed as accessories to telephone systems, but electronic amplification by vacuum tube made loudspeakers more generally useful...
or the power output of the amplifier
Amplifier
Generally, an amplifier or simply amp, is a device for increasing the power of a signal.In popular use, the term usually describes an electronic amplifier, in which the input "signal" is usually a voltage or a current. In audio applications, amplifiers drive the loudspeakers used in PA systems to...
. This can be viewed as a somewhat deceptive marketing
Marketing
Marketing is the process used to determine what products or services may be of interest to customers, and the strategy to use in sales, communications and business development. It generates the strategy that underlies sales techniques, business communication, and business developments...
ploy, as the total power consumption of the unit will of course be greater than any of its other power ratings, except for, perhaps, the peak power of the amplifier, which is essentially an exaggerated value anyway. Shelf stereo
Shelf stereo
thumb|right|200px|A Magnavox 2.0 shelf stereoThe term shelf stereo refers to any home stereo system that is physically suitable for placement on a shelf or other similar location. Shelf stereo systems are becoming more popular as their capabilities increase while size decreases. The price of shelf...
s and surround sound
Surround sound
Surround sound encompasses a range of techniques such as for enriching the sound reproduction quality of an audio source with audio channels reproduced via additional, discrete speakers. Surround sound is characterized by a listener location or sweet spot where the audio effects work best, and...
receivers are often rated using total system power.
One way to use total system power to get a more accurate estimate of power is to consider the amplifier class which would give an educated guess of the power output by considering the efficiency of the class. For example, class AB amplifiers are around 25 or 50% efficiency while Class D amps are much higher; around 80% or more efficiency. A very exceptional efficiency for a specific Class D amp, the ROHM
Rohm
ROHM Semiconductor is a Japanese electronic parts supplier based in Kyoto, Japan. ROHM was incorporated as Toyo Electronics Industry Corporation by Kenichiro Sato on September 17, 1958. The name was officially changed to Rohm in 1981 and then changed again to "ROHM Semiconductor" in January of...
BD5421efs, operates at 90% efficiency.
In some cases, an audio device may be measured by the total system power of all its loudspeakers by adding all their peak power ratings. Many home theater in a box
Home theater in a box
A "home theater in a box" is an integrated home theater package which "bundles" together a combination DVD player/ multi-channel amplifier , speaker wires, connection cables, a remote control, a set of five or more surround sound speakers and a low-frequency...
systems are rated this way. Often low-end home theater systems' power ratings are taken at a high level of harmonic distortion as well; as high as 10%, which would be painfully noticeable.