«  Beware guitars with effects ... »

I will not repeat here what is said elsewhere, Zam Power actually works fine on my guitar Seagull S6 ... But not with my Ibanez Montage. And this is to warn the owners of this type of guitar I just do this post. The assembly is equipped with effects (chorus, reverb, distortion) that require probably a power (not just a matter of voltage, so) that is not issued by the Zam Power.
So: Very good for guitars with (pre) classical amplification (a real solution!), But not for others ...