I'm trying to do the four cable method using a GT-100, a Peavey Classic 30, and of course my guitar. I've hooked it up according to some diagrams I've found online, but I'm not getting the results I expected: firstly, the volume knobs on the amp aren't doing anything - I'll move them, but no change in volume - only when I move the GT-100's output level, does the volume change. Secondly, changing channels on the amp does nothing. I didn't expect this, and am guessing this isn't what's supposed to happen (does it have anything to do with amp sims on the GT-100, maybe?)

Another thing I'm not so sure about is the point of this exercise: is the whole idea to use the Classic 30's pre-amp to do some pre-processing on the signal it receives, which hasn't as yet been affected by the GT-100? Once the pre-amp does some EQ stuff to the tone, it sends it to the GT-100, which adds its effects, sends to the power amp which boosts the signal which is finally sent to the speaker which vibrates causing the air particles to undulate, eventually reaching your ear drum, which in turn vibrates and sends signals to your brain which is all like: "Hey, that sounds pretty cool, have some endorphins."

I got a bit carried away at the end there.

Kindest and Warmest Regards,
Some dude.
I'm not familiar with the GT-100, but it sounds like you have something hooked up wrong.
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Last edited by Robbgnarly at Oct 6, 2013,
You have it hooked up properly cable wise. For more help in setting it up regarding setting the levels & stuff, go through this> Click here
If your amp's master volume is disabled & the gt100's output level knob is controlling the peavey's volume then your master volume is located before the FX loop of the amp. Be careful when turning the S/R loop 'on' in the gt100. Turn the output level all the way down & then activate the loop & slowly start turning up the output level knob. Another thing is that you may need to change the main output level setting in the system menu to +4dB, the factory default is -10dB probably. Again make sure the output knob or volume pedal in a 'initialized patch' is at its heel position, otherwise you risk going deaf lol

The amp control on the gt100 is a simple relay. you need to go into the master menu & turn the amp control 'on' for it do something. Check it if you haven't before.

The idea of 4CM is to split the effects up in front & after the preamp of the peavey C30. You can even disable the C30 preamp & use the internal preamps of the gt100. Make sure the output select mode is set to stack or combo return. I normally prefer Line/Phones & manually disable the cab sims in the gt10, but you might like the factory default stuff. Turn the preamps in the gt100 off as well when you don't want to use them. The link i gave above covers most stuff, but anyways it will take sometime to get used to it or set it up right. Also you may need to grab some low capacitance cables like these and use them for the amp's fx loop. It helps clear the mud that arises when using so many low quality or high capacitance cables.
Last edited by steven_ferns84 at Oct 6, 2013,