[RuiCanela]

I read that Banzai V2 cmoy kit can be dangerous to your phones, I read it here http://www.diyaudio.com/forums/chip-amps/161250-cmoy-shootout-2.html Can someone explain why ?

 

[nikongod]

Post #17 explains why the user thinks there is a problem, but I think the post is inaccurate. The post confuses virtual ground and real ground. The center of the 2 batteries is ground. period. Nothing fake about it. Op Amps in general dont care if they have +&- rails at exactly the same potential from ground. They may not work at their absolute peak potential, but Id bet against catastrophic failure of anything as a result of this. 
 
Anyways, the technique there  has been in use forever in the Grado RA-1 and its predecessor the Grado HPA-1. 
 
You could test it yourself with just a volt-meter and 2 fresh and 1 "nearly dead" battery. Put the fresh batteries in the amp, see what you got for voltage offset. Put the 1 tired battery in see what you got. switch the tired and fresh battery IN the amp (which wires the hook up to) and see what you got.