USB - Universal Serial Bus

Cables and Connectivity

CIE’s examines the different types of USB and looks at USB version 3.1 in more detail...



Universal Serial Buses are universally recognised; they’re what you use to connect data and power via simple, common connector and cable system. Whether you know your USB as the connection between your PC and accessories like your keyboard and mouse, or it’s what you use to charge up your mobile phone or mp3 player, you can be certain that you will have seen them before.

What Are The Different Types Of USB?

The most common kind of USB is known as a ‘Type A’ connector, and has found use in a huge range of situations, all of which require the transfer of information and power from one device to another.

There have been a range of different USB models in circulation since it was first invented, 18 years ago. The ‘Type B’ is particularly common as well, as are the ‘Mini’ and ‘Micro’ USBs. As devices began to shrink in design, to more easily fit in the hand and aid with their portability, the Mini and Micro models were developed to allow a much smaller and less bulky design.

As devices continue to shrink in size, becoming both smaller and thinner, whilst the demand for a high-speed data and power transfer rate increased, both Micro and Mini USBs are unable to keep up. This is where the latest, and most powerful, version of the USB makes its entrance – the Type C.

What Makes The Type C USB So Special?

As it is brand new to the market, the Type C USB will take some months to appear in the designs of the latest mobile devices. The earliest adopter of the USB Type C was the brand new Apple Macbook. Apple devices are well known for their quality, and the appearance of the Type C in their latest products is a great indicator of the role this new design will play in the future of technology.

Much like the Macro and Mini designs, the Type C is drastically smaller than the more common Type A model. In fact, it is only around a third of the size! Ideal for devices where portability is essential, this cable is much easier to transport than the bulbous designs of previous USBs.

Unlike all previous models, the modern USB can never be plugged in the wrong way. The Type C is completely reversible, making it the first USB to completely bypass the annoying moment when the connector refuses to connect.

Of course, there’s more to the Type C’s release than just the fantastic design. This latest means of connecting two devices together has hit the market at the same time as the brand new USB version 3.1.


What Is USB Version 3.1?

USB Version 3.1 is the new standard for USB specifications, including mechanical and electrical specifications, along with the model’s capabilities. It is worth mentioning that the two releases are available individually, but as it is the new standard, most models of the Type C will feature Version 3.1.

The USB 2.0 specification offered a transfer rate of 480 megabytes per second, so it was a massive upgrade to make the lead to an impressive 5 gigabytes for the 3.0 specification. The 3.1 version promises a theoretical bandwidth of double that – meaning it can have a transfer rate of up to 10GBs.

Version 3.1 also offers incredible improvements to its power transfer rate as well. Whilst the 2.0 USB delivered as much as 2.5 watts of power – which is enough to charge smaller, handheld devices, but is completely unsuitable for larger models – the 3.1 specification can deliver up to an astonishing 100 watts of power. To put that in perspective, the average laptop takes around 60 watts to charge.

As if this wasn’t enough, advances in technology have enabled the 3.1 to offer bi-directional charging capabilities. This means that your device can either receive power, with which it can be charged, or send power to charge accessories from its own battery.

Amazingly, this high wattage can be delivered at the same time as it is transmitting that huge bandwidth of information!


Apple’s Affair With Type C USB Version 3.1

As we mentioned before, the latest Apple Macbook is the earliest adopter of the new and compact USB model. In fact, the model itself was designed with only one other port; a headphone jack.

That means that the new Type C USB version 3.1 port is being relied upon to support power, high-definition video and data transfer. The size of the latest USB design has also been compared to Apple’s Lightning connector, ensuring that it combines high-performance with portable practicality.

What Are The Limits Of USB Specifications?

Despite all the technological innovations which are taking place in the USB world, the one major limitation of modern USBs still has yet to be addressed.

The transmission distance of the USB Version 2.0 specification was limited to an inadequate 5-metre distance. Disappointingly, the transmission distance of both versions 3.0 and 3.1 was lowered to an even more disappointing 4 metres.

This could be a major problem which impedes the efficiency of the connector and cable as a charging accessory, as you would be required to sit very close to the charging source. When you’re looking to extend the practical use of your USB connected devices, you’ll need to consider the options available to increase the limited transmission distance.

How Can I Extend The Reach Of My USB Connections?

One of the most common mistakes that people tend to make, whilst looking for a way to extend the transmission distance of their USBs, is to simply connect two (or more) USB cables together to extend beyond the recommended range. Due to their passive design, this is just not going to work, and can often result in damaged cables.


If you’re looking to extend the range of your USB connections, here are some things you should consider:

  • High-Quality USB Cable - Make certain that you are using high-grade USB cables, as this is going to ensure that you enjoy the greatest possible distance, and performance, from your basic connection.
  • Active USB Repeater Cables - You can purchase ‘active’ USB cables, often referred to as ‘repeater cables’. These accessories will regenerate the USB signal, which allows for a passive and an active USB cable to be connected.

It is important to remember that these active cables are bus-powered, meaning that they drain power from the host device’s USB interface. Therefore, this solution is only really useful for data transmission and not for power transfer.

  • USB Hubs – In a similar way to the active cable extension, a Hub will regenerate the signal at the end of the USB cable, which can then be sent on to another cable. For example, you could connect a 3 metre USB Version 3.1 to the HUB, followed by a 3 metre USB Version 3.1 cable, to give an operating distance of 6 metres.

If you choose to use self-powered Hubs, you could connect multiple models together. No more than 5 hubs in a single chain are recommended, meaning that you can drastically increase the operating range of your USB solution.

Of course, these Hubs will all require their own power sources to operate, so an extremely long system is discouraged.

Whilst these solutions are ideal in certain situations, they are unsuitable for those looking to extend their USB connectivity for any huge distance.

What If I Need To Connect Over A Great Distance?

There are extender kits available which can allow you to send a USB signal to a range of distance, up to an astonishing 100 metres! Typically, extender kits will be composed of a transmitter unit, a receiver unit and an Ethernet cable. The transmitter will be attached to the host device and the receiver unit can, in most cases, be attached to multiple USB devices.

Typically, these components are connected to each other via the Ethernet cable to provide a greatly increased 2-way transmission of USB signals. Fortunately, it won’t be too long before USB 3.1 extenders make an appearance, and transmission distance will no longer an issue!


Got a question for the HowToAV Team?

Thank you for reading our guide on Soundfield voice reinforcement systems. We’ve looked at what Soundfield is and how it can aid children’s learning in the classroom, along with the benefits to the teacher, allowing them to speak to a large number of students at a sound level they are comfortable with. If you have any further questions regarding Soundfield systems then please don’t hesitate to get in touch with our team of AV experts.

Subscribe to our YouTube channel now at for all the latest video casts or send us your questions to

Related Products

back to top
  • UVDB Registered
  • PLASA Member
  • Member of BESA
  • BSI 9001
  • ISCE supporting member