By Rob Stewart - - December 21, 2013

NOTE: For Rob's current music mastering gear information, please refer to the Gear page. 

Here is my second-annual list of "favorite mastering tools"! As I mentioned in 2012, many or most of the items on this list are not current products. Some are several years old. This list details what I am using regularly in my practice this year, and I plan to continue to publish similar lists every year as my facilities evolve. 

Rob's Favorite Music Mastering Tools for 2013

GIK Acoustics Room Treatments

Absorption, diffusion, bass trapping etc.
2012 was my first year in business as an audio mastering engineer, and I was working primarily with home made acoustic treatments, which worked reasonably well. I had been using them for years before in my location recording business. My main challenge was that they didn't look very nice, and to be perfectly honest, I didn't I couldn't always trust what I was hearing which made my job difficult.

When I chose to upgrade my room in early 2013, I decided to put the focus on room acoustics. After all, you can have all the great gear you want, but if your room has poor acoustics, it doesn't really make much difference.

Through extensive research, I chose to work with GIK Acoustics, and I am very glad I did. I have a medium-sized room, which has the potential to create a lot of challenges. I contacted GIK in February 2013, and worked with Glenn Kuras and Bryan Pape who used a drawing I sent them of my room layout, to determine which products would work best for my situation purpose. 

I received all of my GIK panels in April 2013, and had them installed relatively quickly. To this day, I am simply amazed by how they have transformed the sound of my room. I can fully trust what I am hearing, and I can hear mix details even better now, than I could before. 

I couldn't be happier with their products. They are very well built, they look fantastic, and most importantly, they sound great. In my view, GIK Acoustics is a world leader in room acoustics technology. They are passionate about what they do, and have an impressive array of different solutions to fit different needs. 

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Voxengo HarmoniEQ

Dynamic EQ with option to add harmonics.
I have been a fan of Voxengo's products for a long, long time. The first product that I bought was their "Elephant" Mastering Limiter - a fine product that I still use today. 

HarmoniEQ is a great sounding EQ for several reasons. First, you have the option to use it as a plain old EQ - no bells and whistles. This is great, because if you just need a clean sounding, easy to use EQ, this is a great option. 

If your situation calls for adding a bit more "excitement" to a track, you have a few options. There is a dynamics section that allows you to add very subtle compression or expansion to the EQ'd signal. The effect is subtle, but I particularly like the Expansion feature to liven up a mix that needs slightly more dynamics. There is also a harmonics feature. I do not usually use this option in mastering, however, in a mix situation I believe this would be very helpful, and I can imagine that it would work very well on vocals, stringed instruments, and drums in particular. 

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SoX Sound Exchange

A donationware Mastering Grade sample rate converter!
I use SoX for all of my audio mastering projects, and I like it so much that I built a living prototype GUI for it. SoX sounds fantastic, and I would recommend it to anyone who is looking for very high quality, highly configurable sample rate conversion. 

SoX Sound Exchange is donationware. 

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Voxengo Elephant

Transparent Mastering Limiter
Elephant was also on my list last year. As I mentioned then, it is a very transparent limiter, but it also allows you to configure it to function exactly the way you want it to. You can control the transient shape/timing, and the knee so that you can achieve the precise amount of limiting you need, with the least amount of distortion. More information from 2012, here.

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Cockos ReaComp

Transparent compressor
It seems that audio compressors have become a commodity these days. There are thousands available, and many claim to add a certain "color", warmth or "mojo" to your mix. There's nothing wrong with that, but what if you want a compressor that just does its job, and stays out of your way?

Enter ReaComp. Reacomp is part of the ReaPlugs plugin suite offered by Cockos. It has been around for years, and it is freeware, but don't let that fool you! ReaComp is a highly transparent, highly configurable audio compressor. In fact, it is the most highly configurable compressor I have seen yet. This plugin essentially allows you to design your own compressor to suit the needs of almost any musical situation you could think of. Here is a list of what I consider to be the most important features that Reacomp has to offer:
  • Feed back, Feed forward and other detector modes are offered
  • Adjustable RMS window (up to 1000ms) to change from peak sensing to RMS sensing and anywhere in between!
  • Adjustable look ahead (up to 250ms)
  • Standard Attack/Release/Knee settings
  • Parallel compression mode (mix the unprocessed signal back in to varying degrees)
  • You can low pass, high Pass or Band pass the detector input

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Klangfreund LUFS Meter Guess what - the loudness war is ending sooner than you think (in fact one or two top mastering engineers have said it has already ended!).

What's next then? We are slowly returning to a place where music and mixes will have dynamics and excitement again (audiophiles, rejoice!). Many popular music players such as iTunes and others include a feature called "Loudness Normalization" which basically analyzes each song in your library, and adjusts its gain based on its intrinsic loudness. This means that mixes that are highly compressed, limited or maximized will actually be brought down to a lower gain level, while mixes that are wide open and dynamic might actually be brought up a few levels. Both songs will appear to have roughly the same loudness after being normalized, however, on closer listening over a high quality playback system, most listeners will hear that the more dynamic mix will sound more lively, transparent and musical. Finally, musicality is making its return! 

In the last few years, the audio industry has started to measure intrinsic loudness using LUFS (Loudness Units Full Scale), and many medial players do as well. For example, if you turn SoundCheck on in iTunes, it normalizes everything in your library to approximately -16LUFS.

Getting back to Klangfreund LUFS Meter, this is one of a handful of freeware vst LUFS meters available today. It is in an early stage of development, so it is not perfect, but what I like about it is that it provides a historical display of the integrated loudness for the song you are working on. My "wishlist" item for this plugin, is to also include history for the two other measures (Short Term and Momentary). That would allow me to see the dynamics of the whole mix over time. 

UPDATE (May 30 2015): The latest version of LUFS Metering is now available!

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