Thanks Silver Blues,
To my noob point of view, i was thinking "it's maybe wiring like this to prevent interference between they" but, i haven't the electronic learning about this level of technology...
i will trying the two solution and see what happen
1/ the twos chips to ground
2/ the second to +9v just to see if i'm able to hearing difference
RIP Lemmy
courage to the bandmate,son and friends
Life's a bitch