One important part of recording vocals for a music recording or a podcast is to reduce or remove unnecessary background noise. This can be done by using the right equipment, setting appropriate levels and ensuring the most conducive recording environment possible. Below are some tips to reduce or remove background noise from your audio recording.
Reduce background noise during recording
Below are tips that can help to reduce background noise when you are ready to record.
Reduce room noise
The simplest way to minimize background noise even before you start recording is to make sure the recording room is as quiet as possible. Turn off the ceiling fan and air conditioner, make sure you are in a corner where your neighbors’ quarreling cannot reach. Close the windows if necessary and draw up all the curtains. Have a soft carpet if possible. Switch off the television. Check that you do not have any CDs or DVDs in your drive, as these may cause unwanted noise from their spinning as well.
Choose the right mic type
Another important factor is your mic type. If you want a recording as ultra-clean as possible, use a dynamic mic instead of a condenser mic. A dynamic mic usually is directional, which means it picks up sound selectively and from only certain directions. In most cases, a dynamic mic only picks up sound from the back (where the vocalist is) and not the front of the mic. This makes sure you don’t get unnecessary noise. A dynamic mic is also less sensitive than a condenser mic, which ensures it does not pick up excessive noise such as the sound of your breathing or the natural humming in your computer soundcard. A condenser mic, being much more sensitive than a dynamic mic, tends to pick up everything in your recording room, which may not be ideal in some cases. If you need more help, check out our reviews on the best recording microphones for 2016.
Use a pop shield or pop filter for the microphone
Natural “pops” often occur when you record vocals for a song or a podcast. These pops are most prominent when you pronounce certain words that start with ‘b’, ‘p’ or ‘s’. The pop shield or pop filter can help eliminate most of these pops and make sure your recording is as clear as possible. Using a pop shield has a noticeable effect on your recording quality especially when you are recording at a few inches away from the mic, such as for podcast. In contrast, if you are recording at a considerable distance such as in a choir, you may not need to use a pop shield.
Mount the mic on a mic stand
Using a mic stand when recording means you do not need to hold the mic with your hand, which minimizes noise from the movement of your fingers. Hands free recording also minimizes unwanted noise and disruption when you accidentally hit an object or a surface with the microphone.
Check your computer soundcard
Sometimes computer soundcards produce internal noise which may interfere with your recording. Before starting your recording, test the soundcard first by recording with no input. If there is indeed internal noise, you may need to replace the soundcard. Otherwise, shielding the soundcard may help reduce the internal noise. You can do so by stuffing a pillow or a blanket in front of or around the computer.
Remove background noise after recording
Even after you have chosen the best possible environment for recording, sometimes background noise is inevitable. Fortunately, it is possible and quite simple to remove unwanted noise after you have finished recording. This can be achieved by using a software to remove background noise, or to use a noise gate in a digital audio workstation.
Use a software to remove background noise
Among possible choices of audio recording and editing software, I would recommend using Audacity, a free, easy-to-use and beginner-friendly software to remove background noise after recording. Follow this simple procedure below to remove noise:
Open your audio file in Audacity. Select the portion of the recording where there is only background noise.
From the effect drop down menu, select “Noise Reduction” option.
The noise reduction dialog will pop up. Note: you will only need to select the “Get Noise Profile” option is you haven’t selected the background noise portion already. Change the parameters as you see fit and simply click “OK”. It is alright to leave the default settings as they are as well.
That’s it! Your recording now sounds much cleaner without excessive background noise. Feel free to experiment with different parameters to determine which combination works best for you.
Use a noise gate
It is also possible to remove background noise from a different software, for instance a digital audio workstation (DAW), using a noise gate. Most DAWs like Garageband and Ableton Live come with a built-in noise gate, but if yours doesn’t, you can usually find free noise gate plugins to download.
The screenshot below shows an example of a gate in Ableton Live.
Threshold refers to the level below which the sound sample will be attenuated.
Attack refers to the time it takes for the gate to fully open and take effect once the signal passes the specified level. The lower the attack time, the faster the gate will fully open once the signal exceeds the threshold you have specified.
Hold refers to the amount of time the gate is allowed to remain fully open at the highest volume, once the threshold is crossed.
Release is the opposite of Attack, referring to the time it takes for the gate to close once the signal drops below the specified threshold.
One interesting feature in Ableton Live 9, the latest generation of Ableton Live, is the ability to “peek” ahead and predict the signal level, as demonstrated by the Lookahead drop down, so as to improve the gate action.
Live 9 also allows you to specify a Floor level, a minimum level for the signal, so the ambient and noise will not be eliminated entirely.
Finally, a basic gate in Ableton Live 9 allows you to Flip the signal, or to listen to what has been removed.
There are many ways to reduce background noise during a recording session or remove unwanted noise after recording. Experimenting with different conditions and parameters is essential in finding out what works best for you and for which recording purpose.