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How to ensure quality audio

Posted by Marius Oberholster on Tuesday, January 21, 2020 Under: Tips
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Many of you know I absolutely love singing and film making and general content production. You do too, or you won't be reading this in the first place! lol.

Since we're on the same page, I want to share with you a few really crucial things that will help you always produce the best possible audio for your projects. For this post, we're ignoring the hardware aspects of it, like what mic to buy.

1) High Hz and large file sizes does not a quality file make
I've worked with audio for a few years now and I've had my little bubble burst when this one sunk in - quite early on. Just like with images, if detail is lost or just not there, you can't simply make it be there by upping the size of the package that information comes in. For example, if you scale up a 32x32 image to fullHD, your image will still just be a smudgy version of the base 32x32 image, depending on your interpolation method.

The same goes for audio.

If your system only produces 44100Hz, then use that. Don't blow up the file sizes without merit. If you can produce at higher rates and uncompressed audio, it's great, especially if the client needs it. 

But the biggest reason why I'm warning against this is that your customer will in most situations not be listening to the uncompressed version of your song or film. When films go out, they go out like on Netflix, which adjusts to your connection speed (ie, quality vairiations on already compressed files that meets their criteria).

If your file contains blown up audio, that audio can get that much compressed again, meaning if you had a "phone" quality sound effect in a 48000Hz file, it will degrade a lot more when compression is applied afterward and can really stand out in a bad way in the final product - usually with very watery sounding artefacts. I wanted to use Jpeg as another image example, but once quality has been degraded, it reads the degradation quite accurately to store less info without losing additional information - go figure! hahaha.

2) Listen like a mic
Let's do an experiment. Take a moment and just listen. Pay very close attention to every possible sound in your surroundings.

The neighbor's dogs may be barking. The computer makes some noise. Your chair creeks. Birds chirping. Lawn mower going in the distance. A truck going passed the window. People talking. Dishes being put away. Etc.

You will hear that the world is truly a very noisy place!

Now, all mics do not pick up on everything our ears do. Our ears are really really sensitive to environmental sounds. With mics, at least off the shelf mics, you often get technology that serves to cancel a lot of this out, by focussing the diaphragm of the mic. Cardiod mics are a great example of this, HOWEVER, they do not cancel out 100% of the noise.
The best way to handle this is to get to know your equipment! How far can you push the sound levels? Is there a place that is quiet enough to record without having to build a tent in a bedroom, lol, or sitting in your closet.

In my experience, I edit in such a way that most of the environments get removed with noise reduction and noise gate plugins. Dog barks are still the hardest to remove. Other people talking near the recording space is impossible to remove with currently available tech, so I simply re-record after they leave or leave and go record elsewhere.

Be extremely aware of the best time of the day to record by looking at daily activities where you record. If the kitchen is buzzing after lunch, then don't try to record immediately after lunch - you'll just frustrate yourself. Help out and when everyone settles again, go for it! Let your space work for you!

3) Be careful with plugins that claim to clean audio
Audio artefacts come in many flavors. Water being the most common. Others include dulling of the overall dynamic range and weird plosive S'es when compressing.

Noise reduction is seems to be the one that encompasses the worst of these, lol. While it is a very important aspect of cleaning up your audio, I strongly urge you to use caution. Most plugins are not intelligent in identifying sounds and will reduce anything that sounds like the given sample or that falls within the same frequency range. This means that your audio can already sound compressed and watery before you even started really putting the edit together... I've had this happen to me a lot in the past. You'll see the most popular video on my channel has the worst audio, LOL - noise reduction...

You can always apply more varied noise reduction, but you can't fix it if it's overdone - be cautious!

4) Troubleshooting a lack of features
One of my absolute favorite things to do is find work arounds for a lack of features. Don't get me wrong, I really appreciate and need features to be there like the next person, but when you understand there are always work arounds, it doesn't really give you sleepless nights if you can't afford the most expensive software.

Let's take 5.1 surround sound for example. I did not do a true mix for Exodus, but I really want a nice 5.1 surround mix. Now, with the experience I've had with Audacity and Blender, I know I can get like 90% to a true mix, with only needing to make an LFE (Low Frequency Emitter or SubWoofer) channel. In my 5.1 in Blender and Audacity video, I talk about a plug-in that allows you to generate one from stereo.




Another example is progressive panning. Audacity does not support timed panning like it does volume - as far as I know. This means that if you want to do a timed pan, you will duplicate it and set one left and the other right and where they are to meet, you simply use the timed volume to shift loudness between the files and BOOM, timed panning without the feature existing in Audacity.

My biggest recommendation for this kind of problem solving is to know your program inside and out to the best of your ability!

5) Listen listen listen, try try try
(different environments)
Whenever you work with audio in Audacity, you are unfortunately not getting the true picture of how the final will sound. It's extremely close, but I've noticed that it processes audio differently to how the computer runs it when using Media Player or other programs.

In cases where you edit audio, export it every so often and listen to it through VLC or Media Player (all effects turned off please - you don't want false impressions).

Also, don't be afraid to try different things. You'll be amazed at how simply trying something leads to something interesting! Let your basic effects create contrast. Another way to create contrast is to up the main frequencies of the Bass, Mid and Treble ranges. This is very similar, in audio terms, to upping the contrast of an image without letting frequencies on the extremes to blow out.

6) Don't be afraid to do it over
I've lost count of how many times I've had to redo something just because it could really be better. Sometimes just because it turned out awful! hahaha.

One of the best examples here would be how I mix audio in Anvil Studio vs Audacity. Anvil Studio would have a mix that sounds incredible and even if I copy the pans and volume verbatim, it still sound awful in Audacity - but it's still a really great starting point for how I want it to sound.

If you listen to a mix and you really can't find the problem and you just feel it sucks, redo it. It's okay to do it better.
MASSIVE Caution - if you are going to redo something, please save the current one first and redo it on a new project file. If you can't achieve a better result quickly enough - at least you have a backup.

7) Loudness Equalization
This one goes with the previous point - getting a great mix together. Most laptops these days come with something called Loudness Equalization. This enables you to use the laptop speakers without needing to worry about two things:
 - Volume control
 - Blowing the speakers

HOWEVER, this creates what I call a false level. Imagine you are on the sea and the boat is being tossed to and frow by the waves, how accurate will a level be in such a situation? It won't be - it'll tell you the floor is like 20' off kilter. I can't imagine why you'd want a level in such a situation anyway, but you get the idea, lol. Construction of a new bunk while being thrown around on a ship isn't exactly the brightest idea in history, hahaha.

The same goes for editing. You will get excess background noise, excessively loud music and you'll turn it down and it won't go down far enough. You'll try to compress the speech a bit, but won't really sound any different and of course the differences between soft and loud sounds will be almost impossible to discern.

As a caution, discipline yourself to only turn it on when needed and to turn it off otherwise. Also, if you notice that you simply can't turn it off - some laptops have it on and it can't be turned off - don't edit audio on that computer. You'll train yourself wrong.

BONUS) Something cool - Audio SuperResolution
I'm a huge fan of all the deep learning software that has been doing the rounds in recent years. My fav has been the incredible results people have achieved for especially super resolution. There is a company that combines various training models into one, that allows the computer to ID text, people and other objects and thus gives you a much much better result. It is so resource intensive that it requires a cloud service.

I did some digging on whether something similar existed for Audio and there is!

Go and listen to all the samples!! My fav part is that this can be used to actually significantly improve already incredible quality sounds or even just make good sounds incredible! It seems to be able to reverse the degradation from over compression quite a bit, restoring a lot of clarity.

And that is it for this post! I really hope these tips encourage you to keep editing, gives you premission to make mistakes and helps you achieve better sound than before! It's a mission for everyone! :D

Have a great one!!
GOD bless you! (^^,)

In : Tips 


Tags: god  jesus  holy spirit  blender  audio  audacity  quality  editing  recording 
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