Cutting noise from a laptop when recording from USB mic

Well I finally got everything set up to record a reading by my sister using Audacity 2.0.5 and we are using her house as the ambient noise is a lot lower than mine. I am using an Editors Keys SL150 USB studio mic on an HP laptop running windows Vista and find the fan noise is intruding on the otherwise almost silent background noise. My fist step is to get a 5 metre USB cable as mine is only 2 metres long but has anyone found a way to baffle the fan noise from the laptop. The problem is that the reading is 30 minutes long and during that time the fan changes speed and hence volume 8 or 9 times within the reading. I have tried noise removal but it seems to affect the voice a little as I get close to removing the fan noise. I have to be careful the laptop does not overheat so does anyone have any solutions they have used themselves.

The 5 metre cable should allow you to place the laptop outside the room. noise reduction isn’t always perfect, and sometimes it’s a trade-off. Sometimes the recording is better left as-is. Constant low-level noise is the easiest to remove. If you can get the background noise quiet enough, the noise reduction should introduce fewer artifacts.

You can also try a noise gate. (I believe the “Gate” effect is included with the opional effect download.) A noise gate totally “kills” the sound during quiet parts (between sentences, etc). But again, it’s something you have to experiment with… Sometimes the effect can be distracting. I’ve noticed a noise gate kicking in-and-out during some movies. Although I’m not really aware of the background noise, when it suddenly goes dead-silent I get the feeling that sound is cutting-out.

You may be able to increase the signal part of the signal-to-noise ratio. Maybe you can try getting closer to the microphone. But, if you get too close that can introduce other problems. The rule-of-thumb is about 12-inches (30cm), but that’s in a recording studio environment and if you can get closer and still get good sound, that will help. It will also help if you can maintain a strong voice without affecting the “performance”.

Noise (and acoustics) is the biggest and most difficult/expensive issue. The other “basic problems” (distortion, frequency response, and speed/timing problems) are easier to eliminate. If you are complaining about laptop fan noise, I’d say you are doing pretty well! :wink:

Thanks for the info Doug and I now have a 5 metre lead so will give it another go possibly with the laptop in another room as suggested. The house is quite isolated and is double glazed so is very quiet. In fact at the end of the recording I could actually hear the dog snoring slightly. The voice recording is excellent otherwise but to get the correct feeling for the reading the voice is somewhat quiet so if this does not work it may have to be a studio somewhere.

Several notes. USB doesn’t like running long distances very much. If you start having data cracking or other crashes, that may be why. Also, one of the services inside the USB cable is analog, not digital, and it can pick up electrical noise from powerful motors, lighting dimmers and other electrical equipment, longer is worse.

I could actually hear the dog snoring slightly.

Dog Removal Software is a running joke. It’s unlikely anything that low is ever going to be apparent in the final show. If you’re part of a mixed production, the other sounds and music will roll right over it. But even if you’re reading over dead silence, how many friends do you have that listen on a soundstage?

I personally have to compete with Metrobuses and Construction Vehicles when I’m hiking – even sometimes inside the house when I’m listening.


I have a lovely demo recording of Boudleaux Bryant with his song “Love Hurts”.

Towards the end of the song his dog barks - at the end of the recording he drily drawls “excuse the dawg…”

The 5 metre cable I bought was not cheap and is fully screened I believe. It does seem to work fine so I should be ok. The reading is in dead silence and my sisters house is unnaturally quiet so you can pick up breath noises and other sounds. I live near a motorway with a constant roar of traffic and several ambulances or police cars with sirens blaring per day so recording at my house is a no-no. My sister lives 20 miles away and the recording was just a test to see what problems cropped up. The next time I visit I hope to get 2 full readings done with practically no background noise invading the sound. I will be going alone so wont have the wife or the dog with me. Playing back the recording on some reasonable speakers sounds like my sister is standing right next to me so the mic works well, too well sometimes, but I am happy with the result. Thanks for the advice you guys have given me on this subject.

I note that nowhere in that did you mention echoes. Noise is only half the formula. Not recording in the kitchen is the other half.

We can’t easily fix either one.


Hi Koz the room is quite small at around 40 cubic metres and reasonably damped so no echo is audible, in fact the voice is quite dry and may need a tad of reverberation to warm it up a bit. The house has 18 inch solid stone walls and so isolates any outside noise quite well but can get cold at this time of year especially with the central heating turned off to eliminate any noise it makes. I am quite confident that the next recording will be to my satisfaction now I know what problems arose on the test recording.
Edit: Wow that is some echo on the clip you posted. I will post a clip from my test recording but it is on my laptop and I am on my desktop at present and have to go out right now.

Well here as promised is a small section of the 30 minute reading. The original is in WAV file format to preserve the quality.

but can get cold at this time of year

The suffering we do for our craft.

that is some echo on the clip you posted.

That was a clip in the middle of a very nice, professionally shot commercial for some weight-loss product. I can sense what happened. “Hey. We don’t need to pay the studio any more. Anybody can shoot sound.” It was a perfect example of what happens when you shoot sound in the kitchen. I would send them a thank you note, but they might not see it in a positive light.


Good you posted that clip. It has a slight honky sound that usually means Windows Enhanced Services is running on your voice. Grand voice voice by the way. I could listen to that for a very long time.

Here’s how to turn it off.

Take notes what you did in case you like it better with Enhanced Services running. Enhanced Services is designed to filter your voice for conferencing and Skype. It helps suppress room noises and echoes, but can leave your voice honky and tinkling. This is the mobile phone “speakerphone” effect. It’s good for communications, but not so good for entertainment recording.

It destroys musical instruments. It only works OK on voices.


Thanks Koz will check if the enhancements are on or off be fore I do the final recording.

Do a short critical test before you crank through a multi-hour performance. The difference between the two settings can be serious. Without the enhancements can sound much more open and natural, but it can let background sounds through.

We’re not the performer. It’s up to you to tell which one you like – and judge it on a very good sound system or good headphones. We regularly have to talk people out of critical monitoring on their laptop speakers. That tells you next to nothing about the quality of the sound.