I've been looking into bluetooth audio and it seems APT-X is the best codec around for sound quality.

There's a few headphones/speakers from creative and sennheiser out now that can receive APT-X. Does anyone know if it's possible to transmit it from a N900?

Thanks

provided the bluetooth driver allows the CPU to set up any kind of data channel, and IF you could get the codec for linux, then possibly yes.

the a2dp solution on the n800 was purely software until lardman came up with a dsp implementation

the apt-x stuff, at least when I played with it a long time ago, is heavily protected IPR

If Nokia license the apt-X audio codec for use in source devices then yes, the N900 would be compatible with the apt-X enabled Creative speakers and Sennheiser headphones, to enable 'wired' quality over a Bluetooth link.

I'm not sure if bluez currently accepts sending anything other than SBC over the a2dp link. E.g. when I was working on the DSP encoder it wasn't afair possible to even send MP3 (which some headsets can decode directly).

Things may well have changed now though, so we should probably look at the upstream Bluez project to see what's possible.

Out of interest which headphones are these? Mine only decode SBC, so not much motivation to look at anything else.

Cheers guys I will keep an eye on this
Standard bluetooth audio is...not that impressive really

Quite true. I think the best bet is probably to get some headphones that will decode mp3 directly and then patch bluez to allow this.

APT-X looks to be proprietary, and also doesn't seem to have been adopted by many manufacturers.

apt-X has been adopted by a number of Consumer Electronics manufacturers for high quality audio over Bluetooth - Sennheiser, Creative Labs, Motorola, Chord are some recent licensees of the technology. The company is also working with a number of cell phone manufacturers to integrate the tecnology into source devices.

that's quite interesting.

OT: I find it amusing that bluetooth was never really intended for the high data rates required for high quality audio and has been enhanced with ever higher rates and new profiles to support high quality audio, don't know whythey didn't simply design some low-power wifi-enabled headphones!
... and meanwhile wifi has been adapted for short range with very low power to replace bluetooth.

The question is really whether the protocol spec is open or not. If not it's not realistically going to happen unless you fancy reverse engineering it.

OTOH, if it does sound really good, and eventually every pair of headphones supports it, then I guess someone will do just that, but it may well take some time.

i realise this is an excpetionally old topic however I thought it be pointless making a new one based on the same topic. I am looking at getting this to work in the n900 however I guess I would need to ask apt-x themselves to develop as this is not an open source codec.However according to this page it appears that the processor on the n900 is just not supported.

http://www.aptx.com/Technology-Portf...Bluetooth.aspx