It can be useful if you can find free IR's (there are tons available on the web) that you like and want to learn to mix your own. So you don't have to buy anything to use cab lab. You want 48k wav files to use in the Fractal units. York Audio is my favorite IR vendor, and I have quite a few of his packs.
My advice is to experiment with mixing your own blends on the FM3 in the cab block using the thousands of legacy IR's or the Dynacabs.
It is very common to mix a dynamic mic (for bite) with a condenser or ribbon mic (for thickness).
The legacy IR's are named to make this easy.
Examples of dynamic mics are: 57, 421, SM7, 906.
Examples of ribbon mics are: 121, 160 and 313.
Examples of condenser mics are: 4047, 414
Here is a quick example. You can use the mute to hear the individual mics. Use the level controls to make the blend ratio between the two IR's. High and low cuts can help dial it in further.
I
MPORTANT: The level controls DO NOT work like a volume control. The volume remains constant, only the blend ratio changes.
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