Although setting up OX with a separate amplifier head and speaker cabinet is relatively straight forward, making the required connections with an all-in-one combo amp can be a little more confusing at first. This guide will help you through the steps required to set up OX with a combo amp.
Locating the Speaker Output
The first step is locating the combo amp's internal connection between its speaker output and actual speaker. The specific location and style of this connection will vary from amp to amp, but in general it will be found on either the back or bottom panel.
If the connection is found on the back panel (as it is, for example, on a Fender '65 Princeton Reverb), it will be visible by looking at the rear of the combo amp without having to remove anything:
The Fender '65 Princeton Reverb back panel connections with main speaker output highlighted.
However, if you don't see a main speaker output on the exposed back panel, you will need to remove the back panel cover to access it. One common example of a combo amp that needs to have its back panel cover removed is the Fender Hot Rod Deluxe. Once the panel is removed, you will see the speaker output on the bottom panel:
The Fender Hot Rod Deluxe bottom panel connections with main speaker output (C) highlighted.
Note that some combo amps have a hard-wired speaker connection and do not have a speaker output jack at all (for example, a vintage 1972 Fender Vibro Champ). For an amp of this type, you would need to have custom wiring work done by a qualified technician.
Additionally, be sure not to use any Preamp output or Send / Return jacks for speaker connections.
Connecting to OX
Once you have located the speaker output on your combo amp, the next step is to remove the speaker cable that is plugged into it (highlighted in both of the above images). Using a separate speaker cable, connect from the speaker output on the combo amp to the "FROM AMPLIFIER" jack on OX.
Connecting to Speaker
The final step is to connect the combo amp's speaker to the "TO SPEAKER" jack on OX. Since the cable connected to the combo amp's speaker is typically very short, you will likely need a speaker extension cable to reach OX's "TO SPEAKER" jack. Here is one example of the type of extension cable you could use.
Connect this speaker extension cable to the "TO SPEAKER" jack on OX's back panel, set OX's impedance selector to the appropriate value, then power up your amp and OX and start playing!