9

I recently purchased a Blue Yeti USB microphone for use in recording screencasts.

I am using Screenflow to record with and while the sound is excellent in quality there is a nasty hum in the background that is not anything like ambient noise.

I have tried different settings and randomly adjusted the gain, but I am a real noobie on this.

Google searches yielded little or not help, so I am hoping to get some guidance here.

Thanks in advance for the help.

|improve this question
  • 1
    demo sound? mostly you can hear if it digital noise or ambient. – ppumkin Jul 8 '11 at 21:07
  • What frequency? 60 Hz? 120 Hz? 1 kHz? – endolith Jul 8 '11 at 21:40
  • I'm having (I think) a similar problem and I don't know if I've got a faulty mic or if I'm doing something wrong. This is what a screencast sounds like with the Yeti. There's a fair bit of background static. That's present in any recording at home or work in any software (including Audacity). This is what it sounds like with my old USB headset mic. The voice quality isn't as good but there's not that terrible background noise either. – user4292 Jun 28 '13 at 14:15
16

There are several possibilities:

  1. The noise is from the PC power supply. Try using a USB hub that has it's own power supply. If you're using a laptop, try running off of battery and the charger and see which one is better.

  2. As @Matt Jenkins said, maybe the mic is picking up the hum through the desk. I'd like to add here that Matt is talking about mechanical vibrations. The fans and hard drives in your PC/laptop could be vibrating the table which is coupling into the mic. Move the mic and see if the noise goes away.

  3. The noise is caused by EMI/RFI. Try moving the mic around the room and see if it gets more or less noise when in different positions. Try a longer USB cable so you can move it around more. Once you've identified what is causing the EMI/RFI then you can do something about it.

  4. And there is always the possibility that the mic is bad. Try using it on a different computer, in a different building. If you still have problems then get a different mic.

I am not a fan of removing the noise after the recording process. Or, rather, it is much better to remove the source of the noise than to try and filter it out later. Fixing it later is what we in the biz call, "Fixing it in the mix". Sometimes you have no other options, but when you do it is always better to do it right.

|improve this answer
  • I totally agree that noise should be removed at the source where possible, just don't pull it apart- unless you must! – Jim Jul 8 '11 at 20:06
  • Hi David, I attached the microphone to a USB hub that has its own power supply and the problem was completely solved. Great sound. – fmz Jul 10 '11 at 0:47
1

Unless you think the microphone is faulty, In which case you should probably send it back, you should look at processing the signal in software.

Audacity is a great cross platform Sound Editor that has a fantastic noise removal plugin, and it's totally free- Highlight a section of your track that just contains noise, then go to the "Effect" menu and click on "Noise removal", now click the "Get Noise Profile" button. Now highlight the whole track and go back to the Noise Removal plugin and click "Ok", it's pretty darn effective :)

Only pull it apart if you are sure that it's not covered under warranty and you've exhausted all other options.

It might be that the noise level is normal in mic of that type, if you've not used a condenser mic before, the huge gain and noise can be above what you expect.

|improve this answer
  • 1
    I agree with David and Jim. This is a last resort. It would be much better to keep the noise from getting into the signal in the first place. In this case, that should be possible, and will probably clean up the signal in other ways too. – Olin Lathrop Jul 8 '11 at 21:05
1

It could be picking up the hum of your computer through the desk. Try holding it in your hand instead of standing it on the desk.

|improve this answer
  • Or set it on a pillow. – Olin Lathrop Jul 8 '11 at 21:03
1

I had the same problem and held the mic in the air while recording. The HUM went away! It was picking up vibrations from the table, How odd. I put it on a stack of rubber mouse pads and all is well now.

|improve this answer
0

Try grounding the computer case to a pipe or other large metal item close by like metal shelves or a metal desk. This will dissapate any ESD/RFI noise being picked up by the mic wire, you can also try plugging the mic into the front of the case away from the power supply, fan, etc...

|improve this answer