Laptop audio recording issue

September 20, 2007 6:54 AM

Sitting at my desk testing a Headset/Microphone plugged in to the mic/headphone socket of my HP laptop. It is working fine, but is picking up the sound of the hard drive spinning as it records (using audacity). I have never run into this before and I can't even hear the drive spinning while I am working, but in the headphones (and on the recording) you can hear it. I have confirmed it's definitely the hard drive as I can match the drive activity light to the sound in the 'phones. How the hell can I stop it picking this noise up?
posted by worker_bee to Computers & Internet (9 answers total)

Response by poster: whoops sorry for the full question in the preview
posted by worker_bee at 6:55 AM on September 20, 2007

Pick it up. It's getting it through the desktop.

Try folding up a small towel and putting it on that, so that it isn't sitting directly on the desk, if you need to leave it somewhere.
posted by Steven C. Den Beste at 7:02 AM on September 20, 2007

Response by poster: The mic is on a boom on the headset so it's not sitting on the desk - probably picking it up through the mic socket somehow?
posted by worker_bee at 7:08 AM on September 20, 2007

As long as the headset is sitting on the desk, the mic will pick up the computer that's on the same desk.

It isn't going to get it through the socket because the wire is long and flexible -- a terrible conductor of sound. The desktop and the plastic of the headset, on the other hand, including the boom arm, are excellent sound conductors.
posted by Steven C. Den Beste at 7:33 AM on September 20, 2007

I get this if the primary OS volume is low and have the volume of the speakers very high to compensate. Does your laptop's volume control use the OS one, or is it separate?
posted by jwells at 7:35 AM on September 20, 2007

Unfortunately, the sound chips/electronics on most laptops are not that good when it comes to sound, hence they're prone to picking up electrical interference etc. This happens especially if you have gain ("recording level") cranked up when recording from the mic, but on some laptops you can't get rid of it. If you're just listening to sounds, make sure the recording controls ("microphone","line-in" etc) are set to zero. If you're recording only use the one you're actually recording from.

Sounds like you would be ripe for some sort of external audio interface, however, these might be too expensive if the only thing you need is clean audio. USB headsets bypass the circuitry which makes them much cleaner. But try the output/recording settings first.
posted by phax at 7:40 AM on September 20, 2007 [2 favorites]

phax has it. If this is an onboard soundcard, you're pretty much boned—it's just not isolated well enough from the rest of the system to provide a pristine audio channel. You know how the lights dim a little some places when someone turns on the vacuum cleaner? Ah so.

It is almost certainly not physical vibration from the hard drive.

If you're just using this for headset purposes—conversation, etc—you may want to pick up a USB headset as your cheapest option. If you do any recording where you'd be concerned about noise on the channel, consider an external sound device. M-Audio makes some decent ~$100 options, and they're not the only folks in the game.
posted by cortex at 7:58 AM on September 20, 2007

Response by poster: Thanks for the suggestions. The headset is on my head (!) so its unlikely it is picking up the sound of the drive from the desk. Looks like I have to get out and get a USB headset and mic and drop this crappy one I have in the trash can.
posted by worker_bee at 8:33 AM on September 20, 2007

You can get a "usb audio" adapter for under ten bucks, and continue using your existing headset. (hooray ebay!) Not audiophile quality, but it should isolate you from some of the local power glitches on the motherboard. (And if you're the hardware type, adding a stabilizing capacitor to the dongle's power pins would be easy.)
posted by Myself at 10:52 PM on September 20, 2007