Bluetooth 4.0 and compatability to previous versions

[Noodles141]

I have been doing a little bit of reading and haven't been able to find the specific answers I want about the newest version of Bluetooth. What i know is that it goes under the name of low energy but isn't necessarily low energy as it has 3 states, the low energy state, normal state and then a high state for faster data transfer speed which makes me think the LE state is a low data transfer speed. I also know that it is backwards compatible so it is able to connect to older version of Bluetooth. What I'm wanting to know specifically is what draw backs are there to connecting a Bluetooth LE device like a phone to a device that works on an older version on Bluetooth, ie battery consumption for said phone, possible older versions of Bluetooth that might not work, anything else that might be of concern. To narrow this down even more i could also ask a question about audio transfer rate as I am looking to invest in a pair of Bluetooth headsets, I'm not looking for any recommendations but would like to know if i should wait till i can find a good Bluetooth 4.0 headset or just go for a headset working on an older version of Bluetooth?

 

[unclejed613]

bluetooth 4.0 will likely be different because it has an advanced feature set. these new features will not be shared by older devices, but the bluetooth 4.0 device will be able to handle all of the features of the older devices.

the LE data rate being slower is because it sends data at the same bitrate, but in short bursts, which reduces the duty cycle of the transmitter without sacrificing signal strength.

 

[RCinFLA]

There are incompatible 4.0 only chips (usually used when device is very power conscience, running off coin cell battery), and dual mode backwards compatible chips.

Apple 4S/5S and Samsung G3/G4 use dual mode.

 

[hunstoer]

most device just didn't catch the pace the new version bluetooth