The most important criterion when buying a Bluetooth adapter is of course that it can be connected to the desired device. For this, it needs the correct interface. But also other factors such as the Bluetooth version, the range, and the transmission speed of data play an important role.
Interface: USB, jack, or HDMI
The interface of the Bluetooth adapter decides on which device and how you can use it. The most common are models with a USB interface. They are particularly suitable for use with a PC. Pay attention to whether it is a USB 2.0 or USB 3.0 connection. This has a significant impact on performance.
If your desktop PC does not have USB 3.0, a cheaper adapter with the older standard is of course sufficient. While various types of data can be transferred and processed via USB, other interfaces are more limited. RCA and jack are used exclusively for the transmission of audio signals.
The Bluetooth audio adapters are particularly suitable for connecting wireless headphones, as required for the Nintendo Switch, or sending data to the car radio or stereo system. Adapters with an HDMI or other picture interface are suitable for wireless use of monitors and televisions.
Bluetooth version: Decisive for the data transfer rate
The Bluetooth standard exists since 1999 and has been constantly developed and improved during this time. The individual versions can be distinguished by the attached version number. Today you can only find devices with Bluetooth version 4.0 or higher. There are significant differences:
Bluetooth 4.0 was introduced in October 2010 and brought a reduction of the energy consumption in the low energy mode of the devices. Since Bluetooth 4.1 a simultaneous connection to many devices is possible
Bluetooth 4.2 brought in December 2014 a higher transmission rate in low energy mode and better encryption. The latest version 5.0 has an improved range and speed with lower power consumption
Range: The different Bluetooth classes
For better classification of the different ranges, Bluetooth adapters are divided into 3 classes:
Class 1: Transmission power of 100 milliwatts and up to 100 m range
Class 2: transmission power of 50 milliwatts and up to 50 m range
Class 3: transmission power of 1 milliwatt and up to 10 m range
The higher the transmission power, the higher the power consumption of the devices. This is especially important if it concerns Bluetooth adapters that cannot cover their power consumption via their interface.
They need then an extra power supply via cable or battery. Also, note that the range refers to the conditions outside. In interiors with many walls, it can be quite lower.
These differences with Bluetooth adapters are
The biggest differentiating factor of Bluetooth adapters is what kind of data they can transfer. Information about this is provided by the so-called Bluetooth profiles that a device has. You can find this information in the technical data. But the interface also tells you a lot about the type of data transfer the Bluetooth adapter is intended for.
Bluetooth adapter for transmitting audio signals
Bluetooth Aux adapters with jack, RCA, or USB are perfect for transmitting audio signals in stereo quality. But often the devices do not only transmit audio signals.
They also control important parameters and settings for volume or commands such as play and pause in the background. This makes this type of Bluetooth adapter not only suitable for headphones or stereo systems, but also for hands-free car kits.