What is IR on a speaker?
An impulse response (or IR) is a sonic measurement of the sound of a speaker, room or microphone in relation to a sound source. In guitar terms, this is usually your amp.
What is an IR for Daw?
An Impulse Response file is basically an audio file in wav format. If you try to play the file through an audio player, the audio is so short that you won't hear anything. But when you load it in an IR loader, you end up with an impressive recreation of the guitar amp speaker and equipment used.