Is it possible to use external 48v phantom power with a Telefunken V676 , I have a pair of V676 thats not racked. I have external power supply / xlr in out. But im missing 48v phantom power. Ive got a Behringer ps400 external phantom power box. I´ve heard that this can damage the preamps? Looking for help, anybody? Is it safe to do ? Any other suggestions if this doesnt work?