After Voice Recording - Play-back has background "HUM"

My system is a Windows 10 system with all updates, and am using Audacity 2.1.3. I downloaded the program from the Audacity website and don’t remember having a zip file so I assume it was the .exe installer.

I purchased a new, “Logitech h390” USB headset with “Noise-canceling mic.” After a few voice test recordings, I hear a pronounced “HUM” on playback. I’ve tried everything I could think of including disconnecting the power cord and external monitor in case they were causing the HUM. I contacted Logitec and after working with me a few days and not being able to resolve the problem, they sent me another new, “Logitech h390, USB headset with Noise-canceling mic.”

I tried the new headset today and still have the HUM. Since the odds are slim that I have two bad, “Brand new headsets,” I’m at my wit’s end and reaching out to the forum for help. Since I’m new to Audacity, I don’t know all of the settings to try that would eliminate this HUM.

Thank you very much!

Jim Dougherty

I assume this is high-pitch “hum”?

That’s usually noise getting into the mic’s electronics through the USB power. It’s hard to point the finger because it’s either an “unusually” noisy power supply and/or a mic preamp that’s “unusually” sensitive to power supply noise.

A different computer might be better.

I don’t know anything about your particular mic, but the “noise canceling” feature is usually part of the mechanical/acoustic design intended to minimize acoustic background noise. These are typically “communications” mics intended for close-to-the mouth communication intelligibility in noisy environments (it’s the kind of mic used by helicopter pilots). It’s usually not designed for TV announcers or Taylor Swift or “high quality” recording.

Still, it shouldn’t put sound in the recording that wasn’t there.

Make a sound test and post it here. Words aren’t important. Read a cereal box, but do it the way you would normally perform


DVDoug - I hope I’m doing my reply correctly. Was not sure if I go on the “Quote,” or just, “Post a Reply?”

I’ve made the recordings without the power supply connected and no difference. As far as a different computer, I’ve tried my old XP laptop and still had the HUM. That’s why Logitech sent me a new headset. This particular headset is one that was recommended to me. I’ll reply to Kozikowski’s post with the “Test recording,” so you both can hear the HUM.

Please let me know if I’m doing the reply wrong by hitting the “Quote.” Jim

Thank you for your help! Attached is the short recording where you can hear the HUM.


That’s mains hum. It can be removed by pasting the code below into Audacity’s Nyquist prompt effect …

(setf *track* (notch2 *track* 60 10))
(setf *track* (notch2 *track* 120 30))
(setf *track* (notch2 *track* 180 30))
(setf *track* (notch2 *track* 300 30))
(setf *track* (notch2 *track* 240 50))
(setf *track* (notch2 *track* 420 50))
(highpass8 *track*  20)

what notch filter code looks like in Audacity's Nyquist prompt.png
Then apply Nyquist prompt like any other effect, on audio with the hum.