Monday, 7 March 2016

I want some bluetooth headphones.

I want some Bluetooth headphones

  • A2DP - audio
  • AVRCP  - remote control
  • HSP, HFP - telephony
  • CTP - cordless telephony (why not?)

That's the easy bit.
  • Built in mic
  • and voice-dialler.
  • and noise-cancelling mics AND playback
  • and volume-boost for quiet sources (I'm looking at you, DVD player)
  • and AVC/compressor for classical music on noisy trains, planes and auto-mobiles.

That's easy too.

Other inputs:
  • I want it to take a micro-SD card for a built-in mp3 player
  • And even have built-in storage, MTP or FAT32 block device.
  • And have a built-in FM/DAB+ radio.
  • It must charge from micro-USB, and be a USB audio-interface when plugged via USB.
  • I also want a 3.5mm stereo line-in socket so I can use them as normal headphones. But I want it to take a 4-connector 3.5mm jack so that it can function as headphones with mic.
  • It should detect when a 3-connector 3.5mm jack is inserted, and offer a 3.5mm microphone out socket.
  • I also want a 3.5mm line-out that feeds whatever audio source is selected, so that I can feed into an amplifier or to a friend who has the same headphones (so line-out should not necessarily cut off the built-in speakers).

Did I miss anything?
  • It should be able to record to micro-sd or built-in storage. In stereo. From the stereo noise-cancelling microphones any of the other audio sources, including USB, and the phone.
  • I should be able to play from any source to the phone. While recording the phone conversation.
  • And waterproof for jogging in the rain. (Not for me, for joggers).
But not Chrome-cast or Mira-cast. That requires WLAN, and that would be a step too far.

For well less than £100.

On a stick. From standard parts.

BT interface. USB interface. Cross-bar audio mixer. SD interface. GPIO controlled radios.