BM-800 Circuitry with +48V Phantom Power Supply

Thread Starter

Aleksandr Gonzales

Joined Jan 15, 2016
27
Good day!

I beg everyone's indulgence with my question regarding BM-800 Condenser Microphone pairing with +48V Phantom Power. So this is the circuit board of the condenser microphone. I see other videos that the electret microphone doesn't need phantom power. May I know if this circuit will not be damaged if I pair it up with phantom power.

View attachment BM-8003.jpg
View attachment BM-8002.jpgView attachment BM-800.jpg
 

Yaakov

Joined Jan 27, 2019
3,522
From everything I read if this microphone is phantom powered. Why are you uncertain about it? The only other thing I can find is that there are battery powered versions and you'd know if you had one.
 

Thread Starter

Aleksandr Gonzales

Joined Jan 15, 2016
27
From everything I read if this microphone is phantom powered. Why are you uncertain about it? The only other thing I can find is that there are battery powered versions and you'd know if you had one.
Thank you for the reply sir. My inquiry is that if there will be gain if I use a Phantom Power and not damage the components? Because thats +48V.
 

Ian0

Joined Aug 7, 2020
3,280
If a microphone isn't meant to be phantom powered, then there is no circuit between the microphone element (pins 2 and 3 on the XLR) and pin 1 (ground). So if it is connected to phantom power, both sides of the microphone element get connected to +48V through 6.8k. The 48V cannot get connected across the microphone element, so it cannot get damaged.
 

andrewmm

Joined Feb 25, 2011
1,757
To reinforce,
In audio, Phatom power is a standard,
to highlight Ian0, it is designed such that it can be always on,

The basis is the a microphone is AC coupled output, so it "does not care" about a DC applied to its output.
48 V is used as its below the low voltage directive, and current limited,
 

Ian0

Joined Aug 7, 2020
3,280
You can't believe everything you read on the internet, but . . . .
https://www.iconnectivity.com/blog/historyofphantompower
In 1966, an engineer from Neumann visited NRK, the Norwegian Broadcasting Corporation, to discuss their new, Solid State microphones with them. NRK said, "That's brilliant, but they have to be Phantom Powered".
Norway has very little daylight, and to make up for this, their studios were equipped with auxiliary lighting, which was fed by a 48v power supply.
It was an ideal power source for the new Phantom Power design, and hence Neumann, and every other microphone manufacturer since has used 48v as a standard.

So, over fifty years on, we can thank the Norwegian Broadcasting Corporation for convincing Neumann to adopt 48v Power, via Phantom, as a standard. One we still use to this day.


I always thought that it had something to do with the telephone system being run on 48V DC.
And as the telephone system predates the safety standards, I also wonder if 48V was established as the highest "safe" voltage, because otherwise it would have made a lot of telephone connectors illegal; and also because I don't think anyone has ever died by being electrocuted by a telephone.
 
Top