May Wireless House Speakers Provide High-Fidelity Music?

Have you ever wondered what some of the technical language means that vendors take in order to show the performance of wireless outdoor speakers shown at In this article, I am going to clarify a commonly used specification: THD or “total harmonic distortion”. It is often hard to pick a suitable pair of wireless speakers given the huge amount of products. Aside from looks, you will often be confronted with having to examine a few of the technical specifications. THD is usually not as easily understood as some other frequently utilized terms such as “signal-to-noise ratio” or “frequency response”. THD is expressed either in percent or in decibel and shows how much the signal that the speaker outputs differs from the audio signal that is input into the speaker. The percentage given as THD describes which amount of energy which is radiated by the speaker are higher harmonics versus the original audio. 10% would mean that one 10th is distortion. 1% would mean one hundredth et cetera. 10% is equal to -20 dB whilst 1% equals -40 dB.

wireless speakers

Harmonic distortion in a wireless loudspeaker is really the consequence of a few components, such as the power amplifier which is built into the speaker in order to drive the loudspeaker element. The audio amplifier itself is going to have a specific level of distortion. Normally the distortion of the amplifier will be higher the more output power it supplies to the speaker. Generally producers will show amp distortion based on a specific amount of output power, by and large a lot less than the rated highest amplifier output power. Distortion ratings for various output power levels are usually provided for a few output power levels or as a diagram listing distortion versus output power. Both of these methods allow to better evaluate the quality of the amplifier.Furthermore, please note that distortion typically is measured for a specific test tone frequency. Commonly a 1 kHz sine wave tone is used during the measurement. This allows evaluating equipment from different vendors. Though, distortion normally varies with different frequencies. Many digital amps will show growing distortion amid higher frequency which cannot easily be discovered by glancing at the spec sheet. The next contributing factor is the loudspeaker element itself. The majority of loudspeakers use a diaphragm type driver that is driven by a coil that is suspended in a magnetic field. The magnetic field is excited by the music signal. The change in magnetic flux, however, is not entirely in sync with the music signal due to core losses and other factors. In addition, the type of suspension of the diaphragm will create nonlinear motion. As such the result is distortion brought about by the speaker element. Most suppliers are going to publish harmonic distortion based on the power level as normally the higher the speaker is driven the higher the level of distortion. The overall distortion of the speaker thus is the total of the amplifier distortion in addition to the speaker element distortion. On top of that, there are different contributing factors. The loudspeaker enclose is going to shake to some extent and thus add to the distortion.

wireless speakers

In order to find out the total distortion of a speaker, a signal generator is used that provides an ultra-linear signal to the loudspeaker and also a measurement microphone which is connected to an audio analyzer to determine the amount of harmonics emitted by the speaker. On the other hand, pure sine signals hardly give an accurate indication of the distortion of the cordless speaker with real-world signals. A better distortion analysis is the so-called intermodulation distortion analysis where a test tone which consists of a number of sine waves is used. Then the level of harmonics at other frequencies is calculated.

wireless speakers

In addition, please note that many wireless speakers are going to experience signal distortion during the audio transmission itself. This is mostly the case for transmitters that use analog or FM type transmission. Digital audio transmission on the other hand has the smallest amount of signal distortion. The music is digitized within the transmitter and not affected during the transmission itself. Digital wireless audio transmitters are available at 2.4 GHz and 5.8 GHz.


A Few Recommendations For Choosing Wireless Loudspeakers

Let me have a look at the word “power efficiency” that lets you know how much wireless loudspeakers squander to aid you to select a pair of cordless loudspeakers.

Several issues are the result of cordless speakers that have low power efficiency: Low-efficiency wireless loudspeakers will squander a certain amount of energy as heat and so are more expensive to operate when compared with high-efficiency models due to their greater energy consumption. Heat will not dissipate well through tiny surfaces. Consequently low-efficiency wireless speakers must use heat sinks. Heat sinks as well as fans are heavy, consume room and also produce noise. Cordless loudspeakers with low efficiency can not be put into tight spaces or inside sealed enclosures as they need a good amount of circulation. Wireless speakers with small efficiency need a bigger power supply to output the identical amount of music power as high-efficiency types. An increased level of heat causes further stress on elements. The life expectancy of the cordless loudspeakers could be lowered and reliability could be compromised. High-efficiency cordless loudspeakers in contrast don’t suffer from these issues and can be built very small.

The power efficiency is displayed as a percentage in the wireless speakers data sheet. Various amp topologies deliver different power efficiencies. Class-A amplifiers are usually the least efficient and Class-D the most efficient. Normal power efficiencies range between 25% to 98%. The higher the efficiency figure, the less the amount of power squandered as heat. A 100-Watt amp which has a 50% efficiency would have a power consumption of 200 W. What is less known about efficiency is the fact that this figure isn’t fixed. Actually it differs depending on how much energy the amp offers. For that reason in some cases you will discover efficiency figures for several energy levels in the data sheet. Every music amp will consume a specific amount of energy regardless of whether or not it supplies any kind of power to the loudspeaker. Because of this the smaller the power the amplifier delivers, the lower the power efficiency. For this reason audio producers normally specify the efficiency for the highest audio power that the amplifier can deliver. In order 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 energy the amplifier utilizes whilst being fed a constant sine wave tone. Ordinarily a full power report is plotted to display the dependency of the efficiency on the output power. For this reason the output power is swept through several values. The efficiency at each value is tested plus a power efficiency graph generated.

Wireless speakers that employ switching-mode amplifiers have a switching stage that causes some amount of non-linear behavior. Therefore bluetooth outdoor loudspeakers that use Class-D amps usually offer smaller audio fidelity than types utilizing analog Class-A amplifiers. Subsequently you will need to base your decision on whether you need small dimensions and low energy consumption or maximum music fidelity. Then again, digital amps have come a long way and are providing improved audio fidelity than in the past. Wireless speakers that use Class-T amps come close to the audio fidelity of products that contain analog amplifiers. Therefore selecting a set of cordless speakers which utilize switching amp with good music fidelity is now feasible.