#1
I have a Fender G-Dec amp, would getting this pedal be a waste of time. Does this pedal have effects and sounds that the my amp cant get?
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#2
the pedal has a mixture of effects and a few distortions i think, look it up
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#3
I tried it a few times and it was just interesting, a couple of cool effects like the clean to distorted one modelled after the intro of Voices but the distortions kind of sucked. The only cool thing is that it can go straight to a mixing board and it might give better sounds than your amp, at least from what I suppose you might like (if you are interested in this pedal probably you like Donegan's tone and fender amps usually don't really deliver that kind of sound). I suggest you to check out the Scott Ian signature pedal though, it's more about distortion too but the sounds are better and more varried than the ones on The Weapon.
Guitars:

Ibanez SZ320
Ibanez RG450
Ibanez SC620
Bc Rich Warlock 7 String
ESP LTD SC-607

FX:

Digitech Whammy 4
Line 6 PodXT Live

Amp:

Line 6 Flextone 2