Are you considering to pick a couple of wireless speakers available from Amphony Incorporated? You might be confused by all of the technical jargon utilized by producers to show the quality of their models. I will highlight a commonly used term which, though, ist often misunderstood: “total harmonic distortion” or “THD”.
Wireless speakers are available in all different shapes and sizes. Choosing the right type can frequently be difficult . I am going to shed some light on a frequently utilized term which is used to describe the technical quality of the speaker: “total harmonic distortion” or “THD”. Total harmonic distortion is generally not that well understood. Nevertheless, this term is nonetheless essential by way of determining the quality of a particular type. Other terms, for instance “output power” or “frequency response” are generally easier understood.
In brief, THD shows the difference between the sound which is produced by the speaker versus the audio signal with which the speaker is driven. The most common methods to state distortion are percent in addition to decibel. These two conventions can be converted into one another. A -20 dB or 10% distortion means that one tenth of the radiated audio is a consequence of distortion while -40 dB or 1% would mean that one percent of the energy are harmonic products of the original signal.
Harmonic distortion in a cordless speaker is in fact the result of a number of components, including the power amplifier that is built into the loudspeaker to drive the loudspeaker element. Customarily the bigger the amp is driven the larger the level of amp distortion. For this reason, a number of vendors will show amp distortion based on amplifier output power.
Having amplifier distortion specifications for several output power levels offers a better picture of the amp distortion performance.Typically distortion is measured with a 1 kHz test tone. Distortion, though, is normally dependent on the signal frequency. Most amps will have rising distortion with increasing frequency. Specifically digital class-D amps will show rather large distortion at frequencies above 5 kHz.
Distortion is additionally created by the speaker driver itself. The majority of loudspeakers make use of a driver that carries a voicecoil. This voicecoil is located in a magnetic field. The coil will track the magnetic field which is controlled by the music signal to move the diaphragm. Nonetheless, this movement is not completely linear. As such there is going to be speaker element distortion which also is dependent on the amount of power with which the speaker is driven.
As such both the amplifier and also the speaker element itself add to distortion. Furthermore, there are other factors that also contribute to distortion. The whole level of distortion is the total of all of these factors. Depending on the material used to construct the loudspeaker enclosure, there are going to be vibrations or box resonances. Those typically depend on the sound pressure level, the enclosure shape, the housing material in addition to audio frequency. For that reason extra sound distortion is going to be brought on by the box itself.
In order to figure out the overall distortion of a loudspeaker, a signal generator is utilized which provides an ultra-linear signal to the speaker along with a measurement microphone that is attached to an audio analyzer in order to determine the amount of harmonics radiated by the speaker. However, pure sine signals barely give an accurate indication of the distortion of the cordless loudspeaker with real-world signals. A better distortion analysis is the so-called intermodulation distortion analysis in which a test tone that consists of a number of sine waves is used. Then the number of harmonics at other frequencies is calculated. Cordless speakers are going to also have some amount of distortion during the audio transmission. The amount of distortion is going to depend on the kind of wireless transmission method in addition to the quality of components. Usually 900 MHz FM transmitters have among the highest level of distortion. More sophisticated types utilize digital audio transmission. Normally these transmitters work at 2.4 GHz or 5.8 GHz.