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simply how much distortion do
Have you ever wondered what some of the technical language means that suppliers use in order
to spell out the performance of wireless loudspeakers? In this article, I am going to highlight one
frequently used specification: THD or "total harmonic distortion".
Looking for the perfect model from the vast amount of products, you may have a hard time
comprehending some of the technical jargon and terms that you will find in the specifications of
modern cordless speakers. THD is frequently not as easily understood as a few other frequently
utilized specs like "signal-to-noise ratio" or "frequency response". Briefly, "harmonic distortion"
shows how much the music signal is being deteriorated because of the speaker or in other words
how much the signal deviates from the original signal. There are 2 widespread methods to
articulate harmonic distortion, either in percent (%) or in decibel (dB). If a speaker states a
distortion of 10% as an example then one tenth of the energy radiated by the loudspeaker is
distortion. A distortion of 10% can also be shown as -20 dB. 1% distortion equals -40dB. A
wireless speaker actually has numerous components that contribute to harmonic distortion. One
of those is the built-in power amplifier. This power amplifier is driving the speaker element.
Amplifier distortion normally depends on the amp output power and is from time to time shown for
a few output power levels.
Having amp distortion specs for a few output power levels provides a better picture of the amp
distortion performance.Also, please note that distortion generally is measured for a certain test
tone frequency. Generally a 1 kHz sine wave tone is used during the measurement. However,
amplifier distortion is going to generally increase with rising frequency, in particular in digital classD models.
Distortion is additionally created by the speaker driver itself. Most speakers make use of a driver
that carries a coil. This voicecoil is positioned in a magnetic field. The voicecoil will track the
magnetic field that is controlled by the music signal to move the diaphragm. However, this
movement is not entirely linear. This results in the audio being distorted by the speaker element
itself. Also, the larger to power level with which the wireless outdoor speaker is driven, the larger
the distortion. Often speaker suppliers are going to display distortion for small to moderate power
As such both the amp and the loudspeaker element itself contribute to distortion. Furthermore,
there are different factors that also contribute to distortion. The whole level of distortion is the sum
of all of these factors. Depending on the material used to construct the speaker enclosure, there
will be vibrations or box resonances. Those regularly depend on the sound pressure level, the box
shape, the housing material and audio frequency. Consequently extra sound distortion will be
brought about by the box itself. Overall distortion is best determined through measurement. A
signal generator is used which supplies a highly linear sine tone to the loudspeaker. The sound is
received by a measurement microphone. The microphone signal is subsequently analyzed by an
audio analyzer. The audio analyzer will compute the amount of higher harmonics or distortion.
Intermodulation distortion analysis is a further technique that gives a better picture of the
loudspeaker distortion performance with real-world signals by using a test signal with 2 harmonics
and measuring how many harmonics at different frequencies are produced by the speaker.
Furthermore, please note that many wireless speakers will experience signal distortion during the
audio transmission itself. This is mostly the case for transmitters which employ analog or FM type
transmission. Superior types are going to employ digital transmission and transmit at 2.4 GHz or
5.8 GHz to reduce signal distortion.