phantom power

thomasw88

quick question around phantom powered mics

singer just bought a sennheiser e865 mic which requires phantom power.   my desk  a yamaha mg166cx  does have it  but its not channel assignable.   all the other mics are not phantomed..  From memory this should be ok  but is there not a specific way of turning the phantom power on/off.  I seem to remember that all the mics should be plugged in before turning on phantom power? Is that right??

ESBlonde

Dynamic mics can take phantom power no problem, as can passive DI boxes.

A balanced line mic cable has two signal cores and a screen, the differential amp in the mixer checks the difference between the two signal cores and eliminates anything not in both giving a nice clear strong signal. The signal cores have phantom power applied (it returns in the screen) so does not interfer with the signal or proper grounding/screening.

Whenever using global phantom power it is advisable to connect all the inputs before switching it on. Sequence for switch on starts at the mic/input device and runs through the signal chain to mixer/inserts/graphic Eq/crossover and finally amps. that way there are no expensive thumps in the speakers. Shutdown is the reverse so start at the amps and power down (wait for the capacitor discharge) and then back up the signal chain.

thomasw88

ESBlonde said:

Dynamic mics can take phantom power no problem, as can passive DI boxes.

A balanced line mic cable has two signal cores and a screen, the differential amp in the mixer checks the difference between the two signal cores and eliminates anything not in both giving a nice clear strong signal. The signal cores have phantom power applied (it returns in the screen) so does not interfer with the signal or proper grounding/screening.

Whenever using global phantom power it is advisable to connect all the inputs before switching it on. Sequence for switch on starts at the mic/input device and runs through the signal chain to mixer/inserts/graphic Eq/crossover and finally amps. that way there are no expensive thumps in the speakers. Shutdown is the reverse so start at the amps and power down (wait for the capacitor discharge) and then back up the signal chain.

so in simplese.

before gig

1. switch on mixing desk
2.connect all mics to mixing desk.
3.switch on phantom power on desk

after gig

1.switch off phantom power
2.remove mics from mixing desk
3.switch off desk


is that correct?

ESBlonde

thomasw88 said:

ESBlonde said:

Dynamic mics can take phantom power no problem, as can passive DI boxes.

A balanced line mic cable has two signal cores and a screen, the differential amp in the mixer checks the difference between the two signal cores and eliminates anything not in both giving a nice clear strong signal. The signal cores have phantom power applied (it returns in the screen) so does not interfer with the signal or proper grounding/screening.

Whenever using global phantom power it is advisable to connect all the inputs before switching it on. Sequence for switch on starts at the mic/input device and runs through the signal chain to mixer/inserts/graphic Eq/crossover and finally amps. that way there are no expensive thumps in the speakers. Shutdown is the reverse so start at the amps and power down (wait for the capacitor discharge) and then back up the signal chain.

so in simplese.

before gig

1. switch on mixing desk
2.connect all mics to mixing desk.
3.switch on phantom power on desk

after gig

1.switch off phantom power
2.remove mics from mixing desk
3.switch off desk


is that correct?

Yes and no. Plug everything in. If the mic has a switch do that first. then the desk then phantom then the power amps or whatever is after the desk. working from input device to speaker. Switch off is the reverse sequence.