Videomaker – Learn video production and editing, camera reviews › Forums › Technique › Sound › Mic+recorder on DSLR for surround (post)purpose › What I use is one of these –
What I use is one of these – http://www.ebay.com/itm/8GB-Digital-MP3-Player-Audio-Voice-Recorder-Rechargeable-Dictaphone-Telephone-/222317789532?var=&hash=item33c32c415c:m:mM1Pa8BZrL7W5Kg3ybsPFkA
I can either plug a Mic into it or my 6 channel mixer and it has the plus of being a MP3 player when not using it to record something. If you want true surround sound, You will need an Audio Mixer and several Microphones. Then you will need to sync everything up. Unless your Video Editing Program has the ability to sync up Audio, then then best way is gather all the Microphones, have them within a Loud clap you make in front of the recording Camera. Then without turning off anything, place microphones where needed and start recording the scenes.