DIY Mastering Part 2: Before You Start - Mastering Media Blog

Sunday, 16 March 2008

DIY Mastering Part 2: Before You Start

Before getting into more detail, there are some ground rules to be covered. All of these are important guidelines for any mastering engineer. I'll spread them over a few posts, but we'll start with rules for before you start mastering.

1: Always use a fixed listening environment

Which means level, room, monitors - the whole thing. Mastering is the art of turning a collection of pieces, songs, tracks, into an album. (Or single, or EP...) We're trying to judge impact, pace, atmosphere, dynamics and timing ( amongst others ) - in fact, as a professional mastering engineer I'm almost trying to second-guess the artist. To make a fair and accurate judgement compared with all those other discs, we have to be 100% confident we know what we're listening to, which means eliminating variables in the listening environment. The same goes for any room used for mastering - it needs to be as good as possible.

I'm going to cover room acoustics and treatment in a later post, but the first and most significant thing to control is the level - ie. how loud you listen to the music. I have two levels I master at - one is 12 dB below the other, and I switch between them throughout a session. The exact level you use isn't critical, but it needs to be consistent. (For the technically minded, use an SPL meter and generate pink noise at -18 dBFS. In my room this corresponds to a C-weighted SPL of 79 dB SPL.)

Then listen long and hard to some good CDs. Figure out which ones you consider to sound perfect, which ones sound too loud, which too soft, which too bassy, which too bright. You might decide to use a slightly higher or lower level than I've suggested to suit your comfort or taste, but there are very good reasons for sticking close to this reference level.

You'll probably find that a large number of recently mastered "classic" albums sound absolutely fantastic at this level, and also that many of the newest sound uncomfortably loud - check out my first DIY post for more about loudness.

Once you've settled on a level - stick with it. If you work at it for long enough you'll develop an instinct for the perfect level for any piece of music, and more importantly you'll avoid being tricked by the Fletcher-Munsen effect; in a nutshell, quiet sounds appear duller and thinner - ie. if you master with your level too low the chances are you'll add too much bass or top, and vica versa.

2: Use full-range, FLAT monitors

A CD is capable of reproducing a frequency-range of 20 Hz to 20 kHz. Your monitors need to come close to this - anything they can't reproduce, you can't hear, and may misjudge. In a pro mastering room this generally means the monitors will be big, and expensive. (In most mastering-houses they may easily cost more than a family car !) So try to choose neutral, accurate speakers, with a flat frequency response - perhaps bland-sounding to some ears, because that way you know it's the music that sounds great, not the monitoring. B&W make some superb hi-fi speakers which could be suitable for DIY mastering.

Ideally you should master on different monitors than you mix on, and even in a different room. This is partly to get a fresh perspective on what you're listening to, but also it means that if there are problems or limitations with the monitors you mixed on, you are more likely to spot this. If you're going the DIY route obviously this won't be easy, but the next best thing is to listen to your mastered audio in as many different places as possible. If it consistently sounds boomy, it probably has too much bass. But problems that you only hear on one system are more likely to be to do with the setup of that system.

One good tip is to setup your home stereo speakers in the mastering room, assuming they're decent quality - since you listen to most of your music on these, you may be much more sensitive to mastering judgements listening to them. Even listening on a favourite pair of headphones can be useful. But remember the golden rule - pick two mastering levels (three at most) and only use these when mastering.

3. Use a loudness meter

As I said in my first DIY post, perhaps the most important thing a mastering engineer does (apart from put the right tracks on the CD, in the right order !) is to choose a consistent, musical level for each track. The most important tool for deciding this is your ears, but meters giving you an objective measurement of the level are invaluable. Most people will probably find it easier to use the digital metering offered by a piece of software, but I still have a soft spot for the analogue needle, or VU meter.

Whichever you decide on, the most important think to know is why bother to use a loudness meter ? Because the absolute and relative loudness' of tracks on an album have an immense effect on their perceived sound and a peak meter is virtually useless for judging loudness. The classic example is the human voice - a very quiet voice can have an extremely high peak level. It "looks" loud on a digital meter, but it sounds quiet. A VU or digital loudness meter looks much more as things sound in terms of level. If you learn how the meter relates to loudness it'll help you make good judgements in "mastering".

More guidelines in a later post...


Gabriel M said...

Thank you very much for this truly interesting blog. I'm actualy producing electronic music and I'm know that I have some talent and my music have is very own personality but what a shame that's its not sounding like I want...But with your advice I'm more confident about compressing/limiting... I have a pair of polk audio RT800 as reference monitor;45hz to 25khz. They are my pride and joy :D Thx again. Just so you know; I'm this king of guy who forget to sleep and eat while working on his stuff but I find out that i'm better when I am completly restless... Cheer

Ian Shepherd said...

Hi Gabriel,

Thanks for your comment, and nice to "meet" you !

I've written lots of other posts on compression on my new blog, for example here's one of my favourites:


Hope you find it helpful,



-d- said...

Hi Ian
Thanks so much for such a blog where as a reader the intrinsic message i get from you is that of an educated person willing to share his pots of gold which he discovered over the course of his career, instead of an arrogant voice of authority mansplaining to the world the condition of the rising generation of hopeless sound engineers. Thank you very much, truly.

I'm currently enrolled in an established sound institution in Oxford where your pages are often time referred to - so that's a good thing!

Interesting that you mention BW speakers. I'm not looking for a pair of speakers at the moment but of course doing prior research such as reading up. I've heard loads on PMCs, Genelecs, AEs, and even NS10s. there's a genuine question as to why BWs - and which ones you were referring to.

I hope that 20 years time i'll have half your knowledge and your humble, unabashed and gracious opinions.


-d- said...

ah -
i'm being a clown. moment i hit send and continued reading i realised your answers on DIY part4.

intersting to note that for tracking&mixing, u'd want sounds to jump up and be more interesting whereas a mastering pair of speakers would just prefer eeverything as flat as possible.

good stuff! so much i'm learning just reading such stuff. time to put it into practice!


Ian Shepherd said...

Hi Derrick,

Thanks for your comment - glad you like the site. All my new posts will be here, by the way:

One thing, though - there are no pots of gold - not round this neck of the woods, anyway :-)


blameitontheboo said...

Hi Ian, like many hobby recording engineers I have to use budget kit or even second hand stuff from the net - the Bowers and Wilkins speakers you mention, is there a particular model I could look out for at the right price? There seems to be a fair range here