IR noob question

[fracturematt]

Hello. I just downloaded a pack of IRs from Guitarhack's thread (sorry I can't post the link I'm too new here)

This is my first time using IRs. How do I know if I need a mic with them? Alot of presets just have the mic dropdown blank. What would you suggest?

Thank you.

 

[AlGrenadine]

"Use your ears".
Sometimes, even if the IR was shot with a non-flat mic, adding a mic in the Cab block can be better...

 

[hwplainview]

Using an IR without a mic is probably a more accurate representation of the cab but, as has already been suggested, use your ears.

As a very general rule of thumb, the SM57, R121, and the U87 mics are probably the most common mics that are used in studios in the rock/pop genres. Each has their own tonal characteristic and doesn't always improve the sound but it really depends on what you're going for.

I find it's useful to add a mic if I'm trying to get close to a specific song/album tone - if you read up on the recording process you might get some insight into the gear used. So for example, if your research suggests an engineer used a SM57/421 combination (very common amongst metal bands for example) on a Marshall cab with V30s then obviously matching that set-up in the Cab block will help you get closer to the album tone.