These settings specify the device (amp) that’s connected to the OUTPUT jacks.

Value Explanation
LINE/PHONES (RECORDING)

Choose this setting if you’re using headphones, or if the 
GX-100 is connected to a keyboard amp, mixer, or digital recorder.

JC-120 RETURN

Choose this setting if the GX-100 is connected to the RETURN jack of the Roland JC-120 guitar amp.

JC-120 INPUT

Choose this setting if the GX-100 is connected to the guitar input of a JC-120 guitar amp.

KATANA-100/212 RETURN

Choose this setting if the GX-100 is connected to the RETURN jack of the KATANA-100/212 guitar amp.

KATANA-100/212 INPUT

Choose this setting if the GX-100 is connected to the guitar input of a KATANA-100/212 guitar amp.

KATANA-100 RETURN

Choose this setting if the GX-100 is connected to the RETURN jack of the KATANA-100 guitar amp.

KATANA-100 INPUT

Choose this setting if the GX-100 is connected to the guitar input of a KATANA-100 guitar amp.

TUBE COMBO 212 RETURN This setting is for cases other than the above when connecting to the RETURN of a vacuum tube combo amp (in which the amp and speakers are in a single unit) equipped with two 12” speakers.
TUBE COMBO 212 INPUT This setting is for cases other than the above when connecting to the INPUT of a vacuum tube combo amp (in which the amp and speakers are in a single unit) equipped with two 12” speakers.
TUBE COMBO 112 RETURN This setting is for cases other than the above when connecting to the RETURN of a vacuum tube combo amp (in which the amp and speakers are in a single unit) equipped with one 12” speaker.
TUBE COMBO 112 INPUT This setting is for cases other than the above when connecting to the INPUT of a vacuum tube combo amp (in which the amp and speakers are in a single unit) equipped with one 12” speaker.
TUBE STACK 412 RETURN

This setting is for cases other than the above when connecting to the RETURN of a vacuum tube stack guitar amp (in which the amp and speakers are separate units).

This assumes that the connected speaker cabinet is equipped with four 12” speakers.

TUBE STACK 412 INPUT

This setting is for cases other than the above when connecting to the INPUT of a vacuum tube stack guitar amp (in which the amp and speaker are separate units).

This assumes that the connected speaker cabinet is equipped with four 12” speakers.

BASS AMP WITH TWEETER Use this setting when connecting to a tweeter-equipped bass amp.
BASS AMP NO TWEETER Use this setting when connecting to a bass amp that has no tweeter.