RedSGShredder

Impulses are tools you can use to simulate guitar cabinets. There is a lot of math behind how they work, but all you need to know is that they provide an easy and free way to simulate guitar cabinets that sound more realistic.

Background

When you plug your guitar into an amplifier, two things happen. First, the signal is amplified by the amplification unit. Then, that signal is sent to a speaker cabinet.

A combo amplifier.

Some amplifiers are “combo” amplifiers because they contain the amplifier and the speaker in one unit. These are generally cheaper and smaller.

Other amplifiers and speaker cabinets are separate units. This allows for greater flexibility. The amplifier unit can be replaced if it dies, speaker cabinets can be swapped out for different tones, and so on.

A bass amplifier and cabinet.

Most digital guitar modelers simulate the amplification and the cabinet together, but they usually allow you to choose them separately for flexibility. In our example, we’ll use the modeler to simulate your amplification, and then use an impulse to simulate your guitar cabinet.

Set Up

To get started with impulses, you will need a plugin to your DAW. Then, you need to load the impulses you like, which are just wav files.

1. If you use Mac OS X, you can use LAConvolver which is a free AU. If you use Windows, you can try using the free SIR VST.
2. Personally, I like the Catharsis impulses. To find more, just try a regular web search for guitar impulses.

Example

I will use reamping for these examples. Be sure to read that article before continuing on if you haven’t already.

1. Here’s a dry, unprocessed recording:

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2. For this next example, I’m using a Pod X3 Live to simulate a guitar amplifier and cabinet together. I’m using my usual Mesa Boogie tone.

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3. The next step is to disable the guitar cabinet, but retain the amplifier. To do this, I’ve used Pod Farm to select “No Cabinet” from the gear menu.

The resulting sound is very dry and harsh because there is no cabinet simulation. But this is exactly what we want.

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4. Finally, we can use our impulse. To do this, add the effect and select the wav file. In this example, I’m using the Catharsis Stereo High Presence impulse. Here is the finished product.

The final product. The two effects are Pod Farm and LAConvolver.

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Conclusion

Impulses are just another tool you can use to expand the number of sounds available to you. As you can tell, swapping out the Pod X3 cabinet simulation for an impulse changes the tone drastically. In my example, there is still a lot of work to do. As with any tone, this tone can still be improved using the usual tools like equalization.