Category Archives: Headphone

Myth of USB

USB personally do not like it much, especially since I’m in  one subject at CTU try to implement a USB interface chip processor. Yet it is one of the most popular computer interface now so we can only watch as progressively pushed out version 2.0 and version 3.0 FireWire themotorcyclers displaces. One of the advantages of USB, which apparently caused its massive expansion, the supply voltage of 5 V. associated with it a lot of myths, half-truths and misconceptions. Unfortunately, some behave accordingly, and although they do not jeopardize our and their safety, but then needlessly surprised that something does not work. Two such complementarily associated myths I would like to refute.

Myth One: The USB port can offer you the 500 mA

Untruth. The value of 500 mA is a maximum load current of one USB 2.0 port. The third version of the maximum increase at 900 mA. However, the device can not just start taking the maximum current value. Just after connection, before the enumeration will be allowed to draw a maximum of 100 mA (for USB 3.0 is 150 mA). Only when the computer reads descriptors from the device requires more current and will meet the requirement, the equipment has permitted to remove the maximum current value.

As stated, for example, Wikipedia, current consumption of the device is expressed in one to five units, each unit represents a 100 mA USB 2.0, 150 mA USB 3.0. If you connect to a computer’s USB hub without external power supply (bus powered), a computer orders from all five current units, but also connected device already offers a maximum of one current unit. That is why a lot of USB devices requires the involvement of directly into the computer, or externally powered hub (self-powered).

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Over-ear Earphones

We have decided to finally make a comparison with the best over-ear earphones, i.e. the helmets that cover the ears completely. If you do not know the types of headphones that are you look at our main page or in this guide we explain it more detail. But to summarize say that the over-ear cover the ears completely making that you submerge completely with what you hear.

As we have always done in headphones-Bluetooth we have taken the bestselling over-ear headphones and we have valued them for ending a classification with the best two that we consider to have the best quality at the price you pay for them.

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