I bought a Behringer C1 Condenser Microphone a while ago, along with a Behringer
U-Phoria UM2 audio interface. I don’t usually do vocals, for my tunes but wanted to try out a couple of proper songs. I plugged the mic into the XLR socket on the UM2, put the C1 on a standard mic stand, and switched on the 48v phantom power on the interface. The interface ran into Ableton 9 on my laptop, and I had headphones plugged into the UM2 to monitor my vocals. I armed one of the audio tracks with the input set to the C1 and set the monitor button to “On”. Then came the buzz!
Before even listening to the sound coming out of my headphones, I saw the track level peak at around -48 db, without any sound going into the mic, and the mic input gain turned all the way down.
I tried all sorts of things to eliminate the buzz. Turned up the gain on the mic input on the UM2 and the laptop. Turned down the input level on the audio track. Moved the mic stand around. Put the mic upside down on the stand. Even tried another mic (Shure SM57). Nothing would make the level drop. When I moved nearer to the mic, the noise level increased.
I’d trawled the internet for ages for a solution to this problem. Some pages said to avoid the C1 altogether: high noise floor, poor electronics, too sensitive, and more. Some people were even sending it back. Other potential issues I found included the metal mic stand causing an earth loop, and the mic picking up the 60 Hz hum of the mains in the room at home. Solutions mentioned were: buy a ground lift; unplug my laptop from the mains; turn off all the electrics in the house.
Finally, I read something about using condenser microphones in a proper recording studio. Surely they don’t get hum with the mic switched on! They don’t (as far I can see!). I worked out that their audio interfaces usually have their own power supply, rather than relying on power from a laptop USB socket. The mic is supposed to take +48 volts from the interface, but what if there isn’t enough power coming from the laptop to get the interface to 48v?
Out came my trusty 4-way external USB hub from Amazon, bought for a few quid a couple of years ago. Surely that might raise the power to the UM2? I plugged the hub’s adapter into the mains, the USB cable into the laptop, and the UM2 cable into the 4-way hub. I switched on the 48v supply and armed the track again. This time, no hum! No green bar on the track indicator either! I could even turn up the mic gain on the UM2 without getting any noise!
So, is this the end of the problem? Not quite. If I listen carefully on the headphones, I can still hear a slight hum on a quiet track. This is probably just the C1 picking up noise from the the rest of the house or the laptop fan. If the mic stand is in a slightly different position, the hum comes back. I just move it again, and the hum goes away. However, the external USB hub seems to be the answer, by raising the voltage that makes the C1 work properly, or at least nearer to the 48 volts required to get a clean signal.
If you’re having trouble with hum from the Behringer C1, I hope this solution works for you! If not, then you could always buy a new mic!
By the way, no songs with vocals yet. Just a few of my remixes and instrumentals here on Bandcamp.