I got a line 6 spider 3 hd150 amp head and cab, When i hook up my guitar processor to the amp with my headphones theres this cool effect where when i hold a note, The sound switches to the left then the right speaker channel or whatever. But when i don't use the headphones the effect only works on 1 of the speakers. So my question is are cabs in stereo or mono?
Mono. If you wanted to get a stereo effect you would need two different amps.