We’ve seen a lot of development in the last couple of years in the area of noise reduction. Mike Thornton recently wrote an extended article which goes into detail about many of the popular choices available today and what their strengths and capabilities are. If you haven’t checked it out yet, it’s well worth a read.
With so many options to choose from, what are the key considerations when selecting noise reduction software? Let’s take a look.
Cost
It goes without saying that the price of the software you invest in is a big consideration. With noise reduction software ranging in price from below $100 to several thousand dollars, you need to choose something which suits your budget. This closely ties in with some of the other points we’ll consider below, such as purpose. If you’re working on a few corporate videos and need to reduce the noise on a couple of bits of dialogue, you probably don’t want to dish out for a costly and fully featured software suite. On the other hand, if you’re regularly editing dialogue for motion pictures then you probably want something with a broad set of tools which can reduce different types of noise while leaving the dialogue intact. The cost of the software needs to be justified by the use and benefit you’ll get out of it, along with the financial return you’ll get as a result of having it and being able to use it on projects.
Purpose And Features
We’ve seen a number of plug-ins in the last year or so which use AI algorithms to provide very effective noise reduction for dialogue. While these tools are a great solution for speech or vocal recordings, they aren’t the right choice for anything other than their intended purpose. If, for example, you’re aiming to reduce the background noise on an acoustic guitar recording, you definitely don’t want something which is intended solely to preserve and restore speech.
The type of noise you wish to remove should play a big part in your choice of noise reduction software. Some things to consider include the type of noise you want to remove, what you want to remove it from and also any additional features of the software which you might find useful in the future. If you only need to reduce clipping in recordings then a de-clipper alone is the obvious choice. However, think about the potential benefits of being able to do more by having software which offers a wider set of restoration algorithms. For example, would de-click, de-crackle and de-hum algorithms also be of use to you?
To pose another question, how much do you need the software to be capable of, and which features are essential to you? There are several noise reduction solutions out there which offer a whole suite of tools for tasks such as reduction of wind, reverb, clipping, hums, buzzes, rustle, plosives and in some cases even bird noise. On top of that there’s also general broadband noise reduction, options which are specifically tailored for dialogue and those which allow the un-mixing of instruments. This can be useful for tasks such as reduction of cymbal bleed from other drum mics. Collectively, there are too many options available between the various pieces of software to list here but one important point relating to this is that of whether you’ll be using it for music or post. There are plenty of noise reduction solutions which have post production as their main area of focus but fewer when it comes to music. One tool which deserves a specific mention in this area is Steinberg Spectralayers. With a multitude of music un-mixing features, along with noise reduction, it’s something to consider if music production is your thing.
Privacy
This one is something which only applies to a handful of tools but it’s critical in many situations. I’ve deliberately tried to avoid mentioning every specific piece of software in this article but the topic of privacy requires examples. Tools are now available which allow us to not only reduce the noise in dialogue recordings but also to restore missing frequency components which simply weren’t there in the recording. This can be done with voice re-synthesis. One tool which has provided this capability for a while is Enhance Speech from Adobe. It works well but files need to be uploaded via a web browser before they can be processed and then re-downloaded. This obviously raises serious security concerns and in many workflows audio can under no circumstances be uploaded to someone else’s servers. In audio post for film and TV, sending audio out like that is an absolute no no. Fortunately, an offline tool is available which does a similar job to Adobe Enhance Speech, only better. dxRevive from Accentize can restore absent frequencies, eliminate reverb, reduce noise and clipping and even correct short audio dropouts. The great news as far as privacy is concerned is that it operates as a plug-in in your DAW and all processing is done locally and in real time.
Ease Of Use
Most users would prefer not to have to read through an extensive user guide in order to figure out how to use something, so ease of use is usually an important consideration when choosing any software. With regard to noise reduction, we have options which range from just a single dial which controls the amount of processing, through to spectral editing where we have options to manually go in, identify noise and then use a variety of tools to reduce or remove it. The ease of use should factor into your decision on which noise reduction tools to purchase based on the following points:
How quickly do you need to get results?
Who will be using the software?
Can the user(s) be bothered to read through accompanying literature in order to use it?
Is there a trade off between ease of use and features and if so, does it matter to you?
Is the user interface one which you can stand to look at, potentially for extended periods?
Can the plug-ins be re-sized if required?
The point about who will be using the software is an important one. An audio professional working in audio forensics will need and want more complex software than a video editor who just needs to clean up some location recordings from time to time. Even so, we all need tools which we like the look of, as superficial as that may sound. If you’re going to be working with a set of tools each and every day, the interface should ideally be as aesthetically pleasing as it is functional.
Hardware Or Software?
So far in this article we’ve focused solely on software based solutions. While this is how the majority of users will use noise reduction processing, there are hardware solutions out there too, most notably from CEDAR. Their range of hardware based processors have found a home in many location sound and broadcast scenarios and in those cases, they are just a better solution than something which is entirely software based. The standalone nature of a hardware unit often makes it way more practical than having to run the audio through another audio interface into a computer. This of course ties in closely with the previously mentioned point about cost. Dedicated hardware is not cheap, so it could prove prohibitively expensive if budgets don’t permit. For the right projects though, it’s well worth looking into.
Quality Of Results
Thinking back to the early days of software based noise reduction with Digidesign’s DINR plug-in, the results were not great. At best you could achieve a few dB of noise reduction before artifacts started to creep in. In fact, they did more than just creep in. They came in quite quickly as soon as the amount of noise reduction was increased beyond a fairly minimal amount. That was almost 30 years though, and over time we’ve seen huge advances in the quality of noise reduction and restoration which can be achieved with software. All of the tools available today do a far better job than the ones from back in the day, but even so, you should audition a variety of tools before making a decision on the one which is right for you. Each noise reduction solution has its own strengths and weaknesses and you might find that one introduces fewer artifacts than another on a given type of processing. No tool is perfect and that’s why many of us choose to build an arsenal of tools rather than settling on a single one.
CPU Usage
Some plug-ins are more CPU friendly than others and so before shelling out for a particular noise reduction tool, you should make sure that you can run it smoothly on your computer. Up to date machines will have no problem running any of the currently available tools but some plug-ins will still allow you to run more instances than others and a few can trip up slower, older machines. Try the demos of any software you’re considering and be sure to not only audition their effectiveness but also their efficiency.
Licensing And Compatibility
The question of software licensing has become a thorny one in recent years. In many cases, software vendors have moved over to a monthly subscription model rather than offering perpetual licences. In the case of noise reduction software, in most cases perpetual licences are offered. Some options though, such as Absentia DX and Descript are only available as a subscription. With so much of the other software we use on a day to day basis having also moved over to subscription, there’s always the consideration of whether or not you want to add another monthly outgoing or if you’d prefer to pay a one off fee for noise reduction software and own it forever (or at least until the version you have is no longer supported or no longer works on your OS!).
This brings me onto the topic of compatibility. Do you need the software to work within your DAW, or as a standalone application? Will you be using it on PC or Mac? Do you want to use it inside a video editor like Adobe Premiere Pro or DaVinci Resolve? Check the compatibility before purchasing.
Final Thoughts
At this point I feel that I should mention Mike Thornton’s Audio Restoration Software in 2023 article again. He goes into a lot of detail about the features and pricing of the majority of popular noise reduction options available today. Used in conjunction with this article, it should provide a good resource of information for anyone considering investing in noise reduction tools.
What do you think? Are there any important points we’ve missed? Let us know in the comments.