USB

The Axe-Fx II connects to a computer via USB. Pages 22-24 of the manual describe requirements, installation and capabilities.

USB support is Audio Class 2.0 compliant. There's support for:

• Editing and remote control via Axe-Edit (no MIDI interface required).
• Audio communication (no audio interface required, except when using analog audio).
• Use as an exclusive USB-to-MIDI interface for other products (in I/O > MIDI set USB ADAPTER MODE to ON).

Editing and recording can be done simultaneously.

Drivers for Mac and PC which add USB support are available for download here. Note: ignore the options in the driver's control panel. Source

Notes on USB communication:

• When monitoring audio using the Axe-Fx II itself there's no latency. When monitoring the audio signal from the computer, latency is determined by the host computer capabilities. Source
• High-pitched noise when using an USB connection may be caused by a ground loop. Cliff: "The USB spec calls for grounding the cable at both ends (mistake). This can create a ground loop. Make sure everything is plugged into the same outlet strip." Source
• If you're recording with an application which uses the system selected input (all 4 channels), you will end up with a recording that contains the dry tracks also. The Axe-Fx II currently doesn't let you mute the dry tracks. Source
• The Axe-Fx II cannot connect to a USB stick. Source

In a DAW the Axe-Fx II appears as a 4-In, 2-Out device.