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

Help for Audacity on Windows.
Forum rules
ImageThis forum is for Audacity on Windows.
Please state which version of Windows you are using,
and the exact three-section version number of Audacity from "Help menu > About Audacity".


Audacity 1.2.x and 1.3.x are obsolete and no longer supported. If you still have those versions, please upgrade at https://www.audacityteam.org/download/.
The old forums for those versions are now closed, but you can still read the archives of the 1.2.x and 1.3.x forums.
Post Reply
jamesdougherty
Posts: 6
Joined: Sun Sep 03, 2017 10:11 pm
Operating System: Windows 10

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

Post by jamesdougherty » Thu Sep 28, 2017 10:00 pm

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

DVDdoug
Forum Crew
Posts: 9426
Joined: Fri Sep 10, 2010 11:30 pm
Operating System: Windows 10

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

Post by DVDdoug » Fri Sep 29, 2017 12:48 am

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.

kozikowski
Forum Staff
Posts: 69384
Joined: Thu Aug 02, 2007 5:57 pm
Operating System: macOS 10.13 High Sierra

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

Post by kozikowski » Fri Sep 29, 2017 12:58 am

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

http://www.kozco.com/tech/audacity/Test ... _Clip.html

Koz

jamesdougherty
Posts: 6
Joined: Sun Sep 03, 2017 10:11 pm
Operating System: Windows 10

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

Post by jamesdougherty » Fri Sep 29, 2017 7:14 pm

DVDdoug wrote: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.

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

jamesdougherty
Posts: 6
Joined: Sun Sep 03, 2017 10:11 pm
Operating System: Windows 10

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

Post by jamesdougherty » Fri Sep 29, 2017 7:17 pm

kozikowski wrote: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

http://www.kozco.com/tech/audacity/Test ... _Clip.html

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

Jim
Attachments
HUM Test Recording.wav
File with HUM in the background.
(1.63 MiB) Downloaded 47 times

Trebor
Posts: 9962
Joined: Sat Dec 27, 2008 5:22 pm
Operating System: Windows 8 or 8.1

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

Post by Trebor » Sun Oct 01, 2017 6:42 am

jamesdougherty wrote: ATTACHMENTS HUM Test Recording.wav File with HUM in the background. (1.63 MiB)
That's mains hum. It can be removed by pasting the code below into Audacity's Nyquist prompt effect ...

Code: Select all

(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
what notch filter code looks like in Audacity's Nyquist prompt.png (9.14 KiB) Viewed 752 times
Then apply Nyquist prompt like any other effect, on audio with the hum.

Post Reply