We’ve gone into how to use impulse responses in your mixes before, but we haven’t done a deep dive into what makes a good impulse response (and why it matters so much).
I’d feel like I’d be doing a disservice to everyone if I didn’t go into detail about what I look for in an IR – and not just the ones that JST puts out.
Here are the top things I look for in every impulse response that touches even a portion of my mixes:
I think quality control can have a huge influence over the quality of an impulse response.
Has the gear used to capture the IR been well maintained? What’s the reputation of the engineer that worked on the IR? What kind of detail have they put into their file naming convention?
You aren’t always going to have access to all of this detail, but if you do, it can be a lifesaver when scrolling through IR libraries. If the gear used to capture an IR isn’t up to snuff, no amount of labeling is going to matter. A knock-off SM57 is not an SM57. A tube preamp with a blown tube is not going to sound the same as one with a brand new tube.
Taking this a step further, an engineer that knows what they’re doing when recording should also have some pretty good standards when naming their files as well.
There’s nothing more frustrating than opening a new set of impulse responses for the first time to find that the engineer has gone and named them all IR_1.wav, IR_2.wav, and so on…
Look for the packs that have the naming convention down to amp, preamp, mic & mic placement (example: 6505_API_SM57_OnAxis.wav) and you’re off to the races when it comes to finding EXACTLY what you need when you’re in a rush later on.
Unless you’re looking for some Eastern European, one-of-a-kind, handmade guitar cabinet from the 1940’s that has only been captured in IR format once before it perished in a fire – you get to be picky and look for variety in your impulse responses.
IRs are super easy to capture today, and anyone selling them that’s worth their salt will do what they can to capture every desirable variation you could need from them.
Combine that accessibility to more mics & more speakers, and it’s becoming increasingly easy to find large IR packs with hundreds of options for under $100.
Ask For Feedback
The audio community is constantly growing, and along with that is more accessibility to honest, experienced feedback.
Ask your fellow engineers and guitarists what they think of some of your work with IRs and more often than not, you’re going to get honest feedback about them.
When building the Conquer All series, we reached out to dozens of guys for feedback, and in turn they shared in helping us narrow down the best of the best:
Drewsif Stalin preferred having something mix-ready that could sit well the instant it was added to a guitar track.
Ryan “Fluff” Bruce praises the flexibility of having raw and processed IRs.
Ola Englund preferred the IRs that had been post-processed already, because it got him to the sound he was after quicker than the raw IRs would have.
Start Recording Your Own
By experimenting with recording your own IRs (or even just live-tracking guitars), you’ll be able to visualize your ideal IR tones much faster when shopping around.
Not everyone’s got access to thousands of dollars in amps, mics & preamps, and I get that. But even someone recording a basic guitar amp with a beginner’s setup will quickly see how mic placement and speaker types affect sound.