Paul Walker -- Emergency Dispatch Recording ... 'Dead on Arrival'

First responders to the Paul Walker crash declared the actor dead almost immediately after arriving on the scene ... and TMZ has obtained audio of the call to dispatch.

According to the recording ... the first firefighters arrived less than 3 minutes after a 911 call alerted them to the crash -- and one of their first communications from the scene is "two fatalities" ... and "DOA."

The man on-scene also informs dispatch it's a "Code N" incident ... which means it's a newsworthy event that should be handled with care.

As we previously reported ... several of Paul's friends were on-scene and most likely told firefighters the actor was in the vehicle.

Listen to the audio ... it's clear firefighters had no doubt Paul and Roger Rodas died instantly.