DIY Tetahedral (wireless) corner-speaker system

Hello, I've always wanted to integrate an audio system into a room in a discrete way, utilizing ceiling space. This is my first audio project and I would like some help fleshing out the design. I want to keep this project as DIY as possible so I'm trying my best to avoid having to buy sub-systems unless it compromises quality, volume, or power consumption.

High-level Objectives For this Device: Service 1. Wireless streaming of audio from either computer, laptop or smart phone; the speakers would receive the signals and play audio, nothing more. 2. System must be able to support at least 6 speakers, streaming in-sync. Audio Quality Not 3. Good quality audio output 4. Reliable signal 5. Volume control/EQ maybe? Form Factor 6. Portable/Interchangeable between corners Power 7. Long-life Rechargeable batteries with support for outlet power

With these project reqs. in mind, how do I get started designing the audio circuit? Here is what I have in mind so far:

  1. Bluetooth connectivity, or buying a microcontroller with RF support and streaming music across XBees, or wifi (somehow??)
  2. Build each speaker as a stand-alone receiver with 1. This makes each speaker versatile and hackable/modifiable.

3-5. Not sure what determines these characteristics or enable these features. 6. Tetahedral enclosure design, either made from wood or will be printed. 7. Rechargeable battery pack.