Especially with Productions telerecording, or asynchronously recording remotely, and not in a studio, here is what you need to know about how to get great audio quality in your recordings.
Firstly, what is Bad Audio Quality?
Bad audio quality is when the recording has artifacts in it that bleed into the raw voice. For Productions recording in the same room, it can be less of an issue, but for productions recording remotely, with the actors in different spaces, bad audio quality sounds unnatural. They break the aural suspension of disbelief for the listener.
Sounds of Bad Audio Quality
Humms, Buzzes, and Hisses from household objects such as your fans, refrigerators, air conditioning units, neighbors mowing their lawns, or low-flying aircraft. Listen to the raw sounds of your recording space’ tone. You may need to record at a different time of day, turn off that noise-making machine, or find a way to placate your small furry animals.
Echoes and Room Reflections
Clap your hands in a bathroom, and you can easily hear how the sound bounces around. Go to the corner of a room to clap and you can hear the sound reflected back by that corner. These reflections are more subtle, but in contrast with someone else’s recording, especially if they have their own reflections, they stand out. You may need to change where you record.
Microphone Handling and Position
Once you begin recording, you should not be adjusting your microphone, which makes that bumping noise. Headset Microphones are notorious for slipping or being hit by your chin or needing readjustment.
Record too far away from your microphone and adjusting your volume levels to match the other speakers will also adjust the volume of any background noise. Meanwhile, If you’re too close to the microphone, you run the risk of “peaking”, which is when your volume has overwhelmed your microphone, and anything past it’s maximum is literally clipped off. This is to prevent damage to speakers on playback.
It may take the right mix of experimentation to find a proper distance, especially if a scene requires yelling, which can easily overload the microphone.
Every time you put your lips together while talking, you push a little pop of air out. Consonants, such as P, B, T, D, K, and G, can hit your microphone with enough force to peak the recording, causing it to clip. There are many tricks to manipulate a recording, but cleaning out Breath Pops is difficult at best.
How do we get Good Audio Quality?
The name of the game, after all. Good Audio quality sounds natural and blends well with others with good quality.
Technical Recording Aspects
Before you even hit the record button, make sure you’re set up properly.
The Nyquist Theorem states that to prevent any loss of information when digitally sampling a signal, you have to sample at a rate of at least twice the highest expected signal frequency.
Anything recorded with a sample rate and bit depth higher than 44.1kHz/16-bit is considered high definition (HD) audio. Consider the minimum settings you should record at. However, when it comes to sound, higher quality is better if you can get it, but generally requires better equipment.
Think of it like frame rate in video quality. Instead of seeing 30 images in a second, you’re capturing 44,100 impressions of sound on your microphone. This is why Telephones sound tinny to your ears, they only have a sample rate of 8,000 Hz – less than half of most ears’ natural ability to hear 20,000hz. That is why 44.1kHz satisfies the Nyquist Theorem.
In Audacity, you can check and change your quality preferences with this guide.
In Reaper, these preferences are in 1.12 Setting Up For Audio under Request sample rate/block size
Recording Format and the problem with MP3 files
MP3 files are a “lossy” format, as in they lose audio information to compress it to be a smaller file. Noise Reduction software can remove that audio information as well, so definitely turn any such software off. However, Lossless compression formats, such as .wav files can be large and unwieldy to send to others.
Enter Bit Rate, the number of bits per second encoded in the MP3 file. Bit rates range from 96 to 320 kilobits per second (Kbps), however, 128 Kbps is considered radio quality, while meanwhile 160 Kbps or higher is required for CD Quality. This is also stated as 16-bit, and 24-bit, which is equivalent to 240 Kbps.
In this age of uploading to google drive, we honestly prefer .wav formats.
In Audacity, the quality setting to export as MP3 can be found through this guide.
In Reaper, these preferences are in 21.3 Consolidating and Exporting.
Your Microphone Matters
The built-in microphone for your phone and your laptop microphone does not record quality audio. As we established above, you want 44.1kHz at minimum, but generally, phone built-in microphones record at 15kHz – 20kHz, and laptop microphones tend to be so close to your computer fan, making them incredibly difficult to get clean audio from.
Dynamic vs Condenser
One of the greatest debates in podcasting microphones, but for voice acting and audio fiction, you want a condenser microphone.
A dynamic microphone is better for capturing loud, strong sounds (drums or loud vocals), particularly in a live setting, and is better for talk-level podcasting. However, a condenser microphone is used to capture more delicate sounds and higher frequencies, particularly in a studio setting.
Since we want higher quality recordings, with those higher frequencies, for immersion in audio, a condenser microphone is ideal for giving us a dynamic range in a performer’s recording – even if that means more work getting clean audio.
Analog vs USB vs XLR
Analog audio mics that use your 3.5mm jack rely on the computer system for processing, and their recordings can be affected if they do not have the proper hardware support. However, 3.5mm Microphones tend to have a limited recording range like your phone’s microphone and do not capture the full depth of sound.
Meanwhile, a microphone that connects via USB to your computer has built-in processing digitizing the signal. Their plug-and-play nature may have you troubleshooting their drivers, but they’re affordably priced.
The behemoths in the recording world, XLR microphones are also analog but require a separate audio interface to process their signal. Not only do they give you great quality, but they tend to be more expensive. Depending on how often you’re recording, they can be a great investment and give audio quality well beyond 48khz.
Since we want to use condenser microphones, we need to sanitize our recording space so what we’re recording is suitable quality. Again, you’ll want to turn off any fans, electronics, or anything that makes its own sounds. This can be dangerous during hotter months, so please record with water and take breaks to cool down when recording.
Kill Sound with Sound Proofing
Acoustic Foam is wonderful if you have some lying around. However, Egg Cartons can act as a cheaper option when combined with thicker fabrics. In a pinch, thick blankets, and pillows can be utilized and come with a delightful blanket fort feeling.
Record Inside a Closet
Closets are great for recording, however, be careful of the walls of the closet as they can still be a reflective surface. One suggestion is to record facing the open closet into another room, but you’ll have to test your space to be sure.
Isolate your microphone with a Fabric Box
A great recording solution is to take a Fabric Box and line it with Soundproofing materials. Not only is this great for recording, but it’s a rather cheap solution to building a recording booth.
The Distance away from the Microphone
As a general rule, stick out your pinkie and thumb in the Hang Ten gesture – that is how much distance you should be away from your microphone. Farther away, and you’re more likely to pick up background noise – too close and you risk easily overloading your recording.
Using Audacity? Turn on Show Clipping to see when you Peak and overload your microphone.
Lastly, Use a Pop Filter
Those explosive P’s are the worst to get rid of, but so easily defeatable but merely speaking just to the right or left of the microphone, and using a Pop Filter. Don’t have one? Find a decent sock, and put it over the microphone. It will block that air from hitting your microphone directly.
If you find yourself popping the mic a lot, point your mouth slightly off-center from the microphone so that airflow doesn’t create those pops.