Some Bluetooth devices can still connect over long distances while others can't. What's the difference?

[Min George]

I have seen some Bluetooth devices that can connect over long distances as much as three meters. There are some that connection would fail even in 50CM distances.

What makes the difference between the two kinds of Bluetooth devices?

 

[eLdavis]

I think it most cases, it also has to do with the Bluetooth version. Most versions can cover a larger range.

 

[kit_hung]

I think antenna power and technology version make the big difference. The capable devices use Class One while the weaker ones are only Class Three.