Impulse Response and It’s Importance to Sound Engineers

The term impulse response has long been considered a mystery to everyone except experienced music producers and acoustic engineering graduates. But lately this term is increasingly familiar to guitarists. Then, what is impulse response and how far can a guitarist take advantage of it? ? Let’s find out!!!

Impulse Response (IR) is a sonic measurement of the sound of a speaker, room or microphone in relation to the sound source. In guitar terms, these are usually amps. Once a guitar is connected to an amp there is much more that can affect the character of the sound. Speaker type, room, microphone, preamp or microphone position and the list goes on. The principle of Impulse Response is to capture all the information at once in order to remember all the settings made. This means that no matter where you are, the sound or character of the voice will remain the same as it was previously set down to the details of your microphone placement and the sound of your favorite room.

Impulse Response is usually saved as a generic .wav file. Many companies, producers, and artists release personal Impulse Responses to accurately replicate their voices and sell them freely. Using IR is quite easy, after getting the selected IR file, you can enter it into compatible hardware or software to produce the desired sound. And that’s because lately Impulse Response has become more and more commonly used, many manufacturers offer an easy way to use it.

Impluse Response for Sound Engineer

Impulse Response is often a tool that causes misunderstandings by engineers and producers when it comes to recording guitars. Much like the process of routing a signal to your computer for the first time, getting started with Impulse Response becomes a habit very quickly, and can give you some of the best sound in the digital world.

Another question that often comes up is can I use Impulse Response with amp modeling? If you look closely Amp modeling is a perfect example of a common IR application. Most popular modeling amp types have a built-in way to load your own Impulse Response file, be it your own or purchased.

Here are some examples of IR-compatible modeling amps:

  • Line 6 Helix – using the free Line 6 software, simply connect the Helix to your computer and import your IR files into the ‘Impulse’ tab.
  • Kemper Profiler – use Kemper’s Cab Maker software to convert your IR .wav files into compatible .kipr files. Put the .kipr file then on a USB stick or similar device, then connect it to your Kemper, then can import using the ‘external storage’ feature.
  • Ax-FX – with Ax-FX III, you can simply drag and drop the IR .wav file into the Ax Edit software. To make your files compatible with the Cab Manage feature, you will also need to download the free Cab-Lab software from Fractal to convert the files.

You can also use impulse response in a DAW at home. Like the hardware described above, many DAWs have built-in IR solutions. While some plugins specifically allow you to use impulse response (Amplitube, Positive Grid BIAS).

Along the way Impulse Response quickly became the gold standard for quality and accuracy. The amp simulators and emulators do a great job of emulating as closely as possible, but not to 100%. For beginners, this can be said to be good because you have access to a signal chain that is used by professionals and can be entered directly on the track that is being used instantly. With this, the work is more practical and faster than miking an amp that actually delivers. For those who have been using Impulse Response a little longer, they will certainly have the opportunity to maintain sound consistency in all conditions. Just imagine how easy it would be to overdub & redo different parts!

Ready to try it yourself? Using Impulse Response can be broken down into these easy step:

  1. Open your project session in a DAW containing DI guitars (can also use guitars tracked through your amp headless using a load box)
  2. Run the guitar through the pre-cabinet signal chain you want to use in your amp simulator (stomp-box, amp, etc.)
  3. Make sure the cabinet settings are turned off in the amp simulator
  4. Load Wall of Sound III (or other IR Loader) to channel after amp simulator & before other effects/plugins
  5. Access all your IRs stored in that folder on the left side of the plugin under the “Users” tab
  6. Test! You’ve loaded your Impulse Responses, and as long as you keep the folders where they’re stored, the list will keep updating as your collection grows.
  7. Before you go, don’t miss 5 Ways Impulse Response Will Improve Your Workflow.

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If you’re ready to take your guitar recordings to the next level, grab an evaluation copy of our new Torpedo Wall of Sound III & Impulse Response pack now available at Joey Sturgis Tones. If you have any questions to get started, you can always contact us for help.