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Reference
Reference

Cabs and user IRs

What an impulse response is, how one gets onto the FM9, and the file extension that looks right and does nothing.

Start here

What a User Cab is

An impulse response is a recording of what a mic'd speaker cabinet does to a sound. Someone plays a frequency sweep through a real cab, records the result, and mathematically removes the sweep — what remains is the cabinet's fingerprint, which can then be applied to anything. Fractal call these User Cabs when they are yours and Factory Cabs when they shipped with the unit. They are the same kind of thing.

How much room you have

2,048 factory cabs — everything from the Axe-Fx III plus the AX8's — and 1,024 memory locations for your own, held in a single bank.

FM9 Owner's Manual
Watch out

Two file extensions, and only one of them loads

An IR you are transmitting to the unit is a MIDI System Exclusive file — .syx. The newer .IR extension is used solely for re-mixing inside Cab-Lab and is not what the hardware takes. Fractal flag this explicitly because a download page will often offer both, they sort next to each other, and the wrong one simply does nothing.

Getting them on there

Loading a User Cab

Two routes, and the editor's is much the better one for more than a single file.

  1. 1

    The editor — Manage Cabs

    Drag and drop user cab files into numbered slots, one at a time or in bulk, and manage what is already on the unit from the same place. This is how you handle a Cab Pack without losing track of what went where.

  2. 2

    Or Fractal-Bot, for one at a time

    Set the Cab block to the slot you want to fill — including deliberately selecting an existing user cab if you mean to overwrite it — then send the .syx.

  3. 3

    Then select it

    Click the Cab block in the editor and pick it from the Picker, or select the slot on the unit.

Worth knowing

Note down the bank and slot as you send

A cab lives at a Bank and a Number — "User 1, #215" — and the Cab block selects it by that address rather than by name. So the number you transmitted to is the number you have to select afterwards, and a preset someone shared expects THEIR slot numbering, not yours. Write it down while you are sending; it is far more annoying to find later.

User cabs back up as their own bank

They are one more file in your backup set, separate from presets and separate from SYSTEM. Skipping it means a restore gives you presets that point at cabs which are no longer there.

Where to get them

Fractal's own shop sells professionally produced Cab Packs, including third-party producers. Axe-Change, their file-sharing site, is a large free library. And the unit has an IR Capture utility if you want to photograph your own cabinet — it needs a mic and a preamp, plus either a flat full-range power amp or a speaker-level DI box.

Cab-Lab is a different tool for a different job

Cab-Lab is an IR mixer — it blends several IRs into one, the way an engineer blends several mics on a real cab. Fractal recommend it for capturing too, because the interface is easier than the on-unit utility. It is not required to load an IR someone else made.

There is a Clear All User Cabs utility

Useful for a genuinely fresh start, and it asks you to confirm. It clears every one of them, so make sure your bank backup exists first.

FM9 Owner's Manual