Loadboxes

A loadbox is an IR loader that is meant to be plugged at the power output of a Tube amplifier head. It usually includes an inductive load to simulate the presence of a loudspeaker.

Therefore the input impedance is usually 4 ohms / 8ohms / 16 ohms as would be an electric guitar cabinet.

It is also heavier built as it must be able to dissipate 100W or more into heat.

This is not appropriate for acoustic guitars!!