We are musicians and should not have to be encumbered with the incremental technicalities that in past days were left to engineers. But in embracing digital technology we open opportunities to deal with the total production of a piece of music, not only its composition and performance. Rather than ignore the possibilities within that production, take well spent time to understand the principles of rendering your recording to a higher standard of reproduction through the editing facilities now at your disposal.

However by drifting through the many web-sites or entering forums that expound theories on the subject of mastering, a home based musician can easily become crushed by the tech-speak that goes on – forget it, we can simplify 90% of the basics to provide a more than acceptable framework for our music.

Definitions. The next few paragraphs are excerpts from a variety of musicians who have had more or less experience in this field. Under this you will find the various stages of mastering as I see it – recording tracks, editing them, polishing, and then editing the final mixdown. Remember that during this process you are still wearing the hat of the arranging musician, at least until the mixdown stage.

Bob Katz kicks off - Mastering is an art and a science. Mastering is the final creative and technical step prior to pressing a record album (CD, DVD, cassette, or other medium). Compare mastering to the editor's job of taking a raw manuscript and turning it into a book.

The book editor must understand syntax, grammar, organization and writing style, as well as know the arcane techniques of binding, color separation, printing presses and the like. Likewise, the Mastering engineer marries the art of music with the science of sound.

What Is a Mastering Engineer? The mastering engineer must have a musical as well as technical background, good ears, great equipment, and technical knowledge. Ideally, he should know how to read music, and have an excellent sense of pitch. He knows how to operate a range of specialized technical equipment, much of which is not found in the average recording studio. The successful mastering engineer understands many musical styles (and there are a lot out there!), edits music, and puts it all together with sophisticated digital processing tools.

He is sensitive to the needs of the producer and the artist(s), and treats each project with individual attention. He must understand what will happen to the recording when it hits the radio, the car, the internet, or the home stereo system.

From home musicians - `I'm learning that if you are a one man band it takes more money than what most of us have to spare, and a lot of know-how to havea great sounding recording..I have these books that teach recording but they are geared towards teaching people that has room for a big sound proof area big mixers and a bunch of mics..And these books are not cheap so I have been learning more on my own about recording browsing the net at recording forums.

This seems to be the best way to learn computer home recording on a budget and I recommend that first before buying any books.

It seems in the world of recording there are a number of secrets and techniques, just like any artform...So one of The best ways to learn is to ask experienced people that have a sound you like for help.. `How to get the sound of a solo instrument played in a small concert hall, how to get those power drums and wall of synth sound. By hours of experimenting, cutting pasting panning, adding effects and monitoring you will understand how to piece together a number of tracks. Then it is time to move up to the next level with a sound mastering course, or buy the book. Make sure that they are aimed at smaller studio and home recording.

Further comments of the experts – The Art(s) of Mastering Part 1 Mar 17, 2002 - Contributed By dB Masters Take a brief, high-level look at the role of a mastering engineer, an often overlooked and misunderstood player in the production process. `Mastering is probably the most often misunderstood stage of the audio recording and production process, at least in the world of home recording. Your basic home recording artists record all the tracks to each song, mix them down to a nice stereo mix, and put them on a CD or cassette tape and start handing them out to friends, selling them at shows, giving them to promoters and/or radio DJ's among a hundred other things. Doing it that way you are missing one of the most important stages of the production process, the stage which separates an amateur recording from a professional one.

Any reasonably well trained ear (including those previously mentioned promoters and radio DJ's) can instantly hear an unmastered recording and recognize it as such. Technically speaking, when you record and produce as mentioned above, you are actually promoting yourself with an unfinished "Premaster".

Mastering is the stage at which you virtually stop hearing the recording as a collection of songs, but more as a single musical vision. The job of the mastering engineer is to make the recording flow smoothly from song to song giving it a consistent level and sonic quality.

This is not to say that every song is supposed to sound the same, but that each song sounds like it belongs on the same CD. Nothing is more annoying to the listener, or at least annoying to me when I am the listener, than having to turn the volume up or down from song to song, or if in one song the bass is boomy and obnoxious, but it in the next is smooth and tasteful, thereby possibly causing the need for EQ adjustments between songs depending on listening environments. Do song songs require more bass than others? Absolutely, but if the difference is too great, it sounds like another band is playing the song. You always want the songs to sound like you.’

The Art of Mixing (mastering) – this from Music Maker. `The final part of the production process, it comes after all the tracks have been recorded for a particular song. It involves balancing the volume level of all of the tracks, placing them in the stereo field, treating them with equalization and dynamics processing, adding time based and modulation effects and turning it into a two tack stereo format.

You have to learn how to use various signal processors, effects tricks and techniques to get the most out of the material that you are mixing’. There is more good stuff from this source which will be include below.

Recording – track sequence options

1. It is generally accepted that whatever form of music is being made, a time-keeper is necessary. If you are organized enough to have your song sorted bar by bar, then your drum set comes first. If the song is going to be built up as it goes along, then a clicktrack or simple beat rhythm is required. This can be turned up while recording other tracks to aid in timekeeping.

2. In the same manner, bass would come next, this creates a strong base for the rest of the piece. However usually the song is going through a developmental stage, and the drum time beat will have to suffice. Once all is in its correct place, the song can be re-recorded in this sequence.

3. Generally the lead vocal (or in an instrumental – the lead part), will be done now. Thus the three most important , and generally most obvious (not loudest) parts of the song are up front and the rest is built around them..

Mixing - track recording

Initially editing tracks will mostly be a matter of applying a volume level that enables the composer to get a feel for what is evolving. Some tracks may be given a bit of 3D and atmosphere in the form of panning, reverb and volume control.

This can be done with complete confidence knowing that all adjustments can be altered right to the very end, almost unimaginable only a few years ago. Also make use of the chance to save a version of your song that may only be partially complete if a certain setting gets your attention, i.e. Save as – Song 1 good bass mix, for example. Saving versions of the recording as it progresses only uses a fraction of memory in the form of the .sng file (in the case of n-Track), but provides an invaluable reference.

At some stage about 90% of the recorded tracks will be complete, and only a few short enhancements may be added. Before the work is properly reviewed, apply all of the track editing as follows -

Mixing - listening

Audio CDs do not use WAV as their sound format, using instead Red Book audio. The commonality is that both audio CDs and WAV files have the audio data encoded in PCM. WAV is a data file format for a computer to use that can't be understood by CD players directly. To record WAV files to an Audio CD the file headers must be stripped and the remaining PCM data written directly to the disc as individual tracks with zero padding added to match the CD's sector size.

In the digital domain, PCM (Pulse Code Modulation) is the most straightforward mechanism to store audio. The analog audio is sampled in accordance with the Nyquest theorem and the individual samples are stored sequentially in binary format. The wave file is the most common format for storing PCM data.

Mixing - track editing in the digital workstation.

The degree of editing will depend on the type of music that is being produced. Classical and jazz require the least enhancing, especially as we assume the work to be done in a home environment where complex instrumental ensembles are unlikely. Some work will be required to separate the instruments, and probably subtle reverb applied at the master volume station (overall).

Naturally rock dance and hip hop etc needs great attention to the drum and bass tracks, techniques are given to bolden and tighten these elements. Greater freedom to experiment with backing keyboards, guitars and effects gives the mastering a fuller palette to work from. Prog rock, experimental and electronic genre’s offer maximum diversity for mixing, using options from 1 and 2, plus the opportunity to create at will. Listen to some Porcupine tree, Riverside or Planet X!!

So we must firstly give each track its signature `loudness’ so that we can then apply leveling to place it in the overall picture. Important to remember is that these edits are done in the effects box of each track, and are thus fully reversible , they can be removed or bypassed.

lthough there is no set sequence, the general procedure at this stage of production is; Effects; Equalisation; Compression; Panning; Volume.

Effects – reverb

1. Effects: Do we add effects before or after? Due to excessive background noise from the analogue effects gear of yesteryear, they were usually introduced late into the mix. However, you will quickly note that they contribute towards a tracks `presence’, which in my book, and in theory these days, means that it should actually be applied first. Thus if you have a particular effect such as chorus, reverb or weird that you with to apply to a track, do it first.

1a – Effects – reverb; Reverb will tend to clog the sound and is best used only on the tracks that you want to stand out such as on a lead instrument. Reverb on vocals are most effective when applied to a mono track, but overdo it and the effect can be to push the track back into the mix. However when it comes to live and acoustic tracks where there are few instruments, rather leave it as late as possible, it would be more natural to apply them to the overall mix, which will help blend the sound cohesively.

Remember that what may sound like too little reverb at this stage, may already be too much.. Applied to the master effects it can bring a piece of music together. Or if you only want a reverb effect to round off a song, use the send level control to apply it to the song in its final mixed down stage, but only for the last bar or so.

Effects – Compressing

This is probably the most difficult part of mixing, especially when it comes to miked recordings. We need to reduce the sound level peaks and boost the low level dips to a level that retains dynamic interest and musicality.

This simply put flattens the sound - sinewave, it lifts the valleys and lowers the hills. Apart from making the sound less fatiguing to listen to, it means that we can raise the overall loudness without pushing the sound peaks over 0db. This is known as clipping and leads to distortion. By maintaining the output peaks to under 0db, we are `limiting’ the output.

However at the recording editing stage of mixing, we a only going to apply subtle compression to miked tracks such as vocals and drums, and to acoustic instruments i.e. guitar, bass and sometimes piano. These tracks will require compressing to bring them under control – we don’t want our lead tracks first drowning out the others, then disappearing on occasion. Here is a useful table that I have found on the net. The parameter settings you will find in most traditional layouts.

General compression parameter guidelines.
Attack Release Threshold Ratio Knee
Full track Fastest possible Fastest possible -5dB to -9dB 2:1 to 3:1 Soft
Drums 5ms 10ms or Auto -15dB 5:1 to 8:1 Hard
Synth Bass 4ms to 10ms 10ms -4dB to -8dB 4:1 Hard
Real Bass 4ms to 10ms 10ms -2dB to -10dB 8:1 Hard
Vocals Fastest Possible Lowest possible -3dB to -8dB 4:1 to 12:1 Soft

Sound ratio

The most important adjustment is the RATIO. A ratio of 8:1 means every 8db of volume contrast between loudest and softest is reduced to 1db of output. Obviously this is a high reduction and should only be used in extreme circumstances of loud/soft contrast, such as vocals, brass instruments and in other cases where the performer has gone a bit overboard with the expression.

The THRESHOLD is the input sound level (in dB) over which the compression will be processed. And the third part of general compression is the KNEE, if this is soft the compression will gradually be phased in over the threshold level.

The ATTACK and RELEASE controls are easily altered (how soon the compression is initiated and how long until it is released), and the OUTPUT is usually gained a bit at approx -1.5db to compensate for the overall loss of output after compression.

Done.

Effects - Equalization

We want as much `space’ around the important tracks such as lead vocal, bass, drums and lead instrument as possible to avoid them cloying with each other and the songs backing. There are essentially two ways of doing this. By altering the frequency range output of these tracks so that they don’t clash with each other, and by panning.

Each instrument has its own effective frequency range. Control of this is done either with a PARAMETRIC equalizer which uses a flexible curve that can be shaped to the desired frequency boost or cut, or a GRAPHIC method where a more structured block graph is used. In both methods increasing space above the central line increases output and visa versa. The more sounds we have playing at the same time within the same frequency range, the less distinct each will be.

The most effective method is to isolate each track in turn, and while it is playing open effects for that track, open the graphic equalizer, and subdue as much of the frequency range from either end as possible without changing the tonal quality of that instrument.

This will have to be a bit of a give and take issue, but the results are well worth it. Take this opportunity to remove unnecessary low and high frequencies of each important track. The backing strings will be softer and can occupy these less important areas. Here is an example of manipulation in one situation lifted from a long article - ` When you EQ the Bass drum try boosting the lows and cutting some of the low mids on the drum sound. This will leave room for the Bass Guitar sound in low–mid range’.

And another -` Don't forget that EQ can be CUT to affect tonal quality, not just boosted. Do you want a deeper bass? Cut everything from 5K on up on the bass track. Cutting the highs keeps all the sound in the lower register without getting too dark or flabby’.

Start with track 1 in your workstation and open the graphic EQ. Obviously you will do this in the virtual (listening ), mode. When you have cut as much frequency as possible without making a big change to the tonal qualities of the track, open track 2 and again listen with and without the EQ adjustments. If you have done a good job, the tracks should be much more easy to discern from each other with the EQ in. And so work your way through the tracks.

The graphic below illustrates well the overall effect that is desirable, a Parametric EQ would help with this level of control. (I think that I got this from Home recording connection).

This is an illustration of EQing a track using the parametric EQ and is known as notching out, and requires experience if you are not to degrade sound quality.

This table below gives a few useful pointers..

Instrument Key Frequencies
Bass Guitar Attack or pluck is increase at 700 or 1KHz; Bottom added at 60 or 80Hz; string noise at 2.5KHz
Bass Drum Slap at 2.5KHz; Bottom at 60 or 80Hz
Snare Drum Fatness at 240Hz; Crispness at 1 to 2.5KHz; Bottom at 60 or 80 Hz
Hi-Hat and Cymbals Shimmer at 7.5 to 10KHz; Klang or gong sound at about 200Hz
Toms Attack at 5KHz; Fullness at 240Hz
Floor Toms Attach at 5KHz; Fullness at 80 or 240Hz
Electric Guitar Body at 240Hz; Clarity at 2.5KHz
Acoustic Guitar Body at 240Hz; Clarity at 2.5KHz; Bottom at 80 or 120Hz
Piano Bass at 80 or 120Hz; Presence at 2.5 to 5 KHz; Crispness at 10KHz; Honky-tonk sound at 2.5KHz as bandwidth is narrowed; Resonance at 40 to 60Hz
Horns Fullness at 120 or 240Hz; Shrill at 2.5 or 5KHz
Voice Fullness at 120Hz; Boominess at 200 to 240Hz; Presence at 5KHz; Sibilance at 2.5KHz; Air at 12 to 15 KHz
Harmonica Fat at 240Hz, bite at 3 to 5KHz
Conga Resonant ring at 200 to 240Hz; Presence and slap at 5KHz

It soon becomes apparent that there is overlap at certain frequencies, and this is where creative EQing such as notching comes in. As you can see from the table above, the region around 240Hz benefits most sound sources, however it would be unusual to have more than two lead tracks requiring this space at the same time.

That’s it.

Effects - panning

When using panning, it is often helpful to envision a music stage in front of you, and place the tracks within that space as you would normally hear at a concert. You may not keep the tracks in this position as you build-up and further define your mix, but it does make a useful starting point.

Indeed, and it is only when listening over headphones that this extra dimension can be appreciated, while the instruments will sound out clearly from each other over speakers. Mastering people talk of a three dimensional virtual stage. Obviously the left and right, but also front and back. There are two ways of creating front and back – volume and reverb. I may add a third – panning, i.e. the wider that a sound is spread, the further away it should be. And for widening, or stereo-enhancing a technique which has its place in more technical genre’s glam and prog rock.

This is done by slightly mis-aligning the two stereo tracks of a recording so that one is a micro second behind the other. Alternately use the pitch shift on one of the tracks to create the difference that greatly enhances the width. Otherwise clone a mono track and create the same effect.

POLISHING

This is a term that comes to mind when I listen to my CD (demo-mode) for yet another time. Does the sound of each song blend with the rest? Are volumes similar and tonal output matching? The sections in which I want a particular instrument to become the focus, does this happen, and do the climaxes climax?

This is a long process, and often adjustments that benefit one area of the song, removes something else. Occasionally one song just shines, attak pace and overall effect are on the button, and you can spend plenty of time trying to find out why and match the other songs of the CD to it. This is why it is worth approaching a studio to finalise the mastering. In reality the home musician can only go so far. A well composed, recorded and arranged piece of music can loose a lot of impact because of average mastering..

Premastering.

Premastering is the process of finishing and polishing-up your mixdown

There is no general rule or recipe how to make things sound good. The first and very basic rule as already mentioned is that the edit should be as close to perfect as possible before you start premastering. Now we are dealing with slight “mistakes” of your material and about smoothing or bringing out some edges, but nothing more. The “colour” itself should not be the target of this process, but the product of your arrangement. If the sound doesn’t come close to your idea by now, do an other arrangement, change something in your track – Premastering won’t help you.

Techniques used in premastering.

Lets start with seeing if the overall frequency balance of the track can be bettered. although in the multitrack we have endevoured to make each track its best, the overall effect may be a little harsh in the high ranges, or boomy in the lower. Also you want all the tracks in a cd to have very similar tonal value.

A graphical analysis can be called up, but I have found that other than indicating sections of the track which lacks sufficient frequency in a narrow range, it can be misleading. At this stage the sound will be the same as before the mixdown, however adjusting tracks will not usually affect the overall tone of the piece. The advantages of the digital workstation can now be appreciated, as you can experiment with the graphic equalizer filter and until satisfaction is gained.

Frequency ranges and their uses.

  • 60Hz
  • Around 60Hz is the low end of your hearing-ability. Underneath this edge, your ears will not find any valuable information. (But if it is loud enough, you can feel it!!!!) This frequency-range should only be used sometimes. I turn is as low as possible it just clutters the overall sound.
  • 60–80Hz
  • The range, where you set up a proper, low Sub-bass is between 60 and 80Hz. But notice, the deeper the sound is, the less can you separate different sources – this is why your bass sounds indifferent and rumbling, as soon as it interferes with e.g. a bassdrum. Best to lower the frency here by a few db.
  • Set your bassdrum between 80 and 120Hz. If you like some more power on the release of the drum, raise it’s bass around 80Hz and lower it’s range at 200–400Hz. Above that is where your bassline lives.
  • 200–400Hz
  • Is a very tricky area! If your whole setup sounds dull, even if you have maximum presence in the high frequencies, 200–400Hz is the area you should worry about. Lower this range, and you’ll receive more transparency and presence in the whole panorama. Much of accidental “LoFi-Charme” can be avoided by gaining or lowering this range.
  • Between 200Hz and 700Hz exists most of the musical information. I usually raise this slightly, and lower slightly on either side.
  • 1000–1600Hz
  • Is the range, where things get this telephone-effect (don’t know, how to describe it properly, but you’ll know what I mean) kind of a resonating, flat sound. If your mix sounds like that, lower this range a bit in a wide band.
  • 2–4KHz
  • Around 2–4KHz our ears do something wicked: You always recognise, this frequencies louder than others, that have exactly the same volume. Lower signals in this range, to “widen” and harmonize your mix.
  • 4–5KHz
  • Is where snares, HiHats and hissing noises get their presence. This range makes a mix sound aggressive, hard and “in the front”. High frequencies above 6 KHz are mentioned to be extra sharp and cutting. So if you get sounds harder then mend to be, lower some narowbanded gap here, to avoid the mix to get too hard, or to interfere too much with the area around 4–5KHz.
  • Above 9KHz
  • You’ll notice a strange thing: This is the range for silky presence and nice transparent sounds. Raise this area, and you’ll hear things more in the front and fresher, lower it, and things step back into the background. If you listen to this frequency-range solo, you’ll recognise it as kind of noisy, but in the whole of a mix it makes sounds spacy and silky wide. I love stereo-effects on this part.
  • Above this you can begin to exponentially reduce. Again as in the low bass this just clutters your other far more important frequencies.

Compression.

Reduction of audio dynamic range, so that the louder passages are made softer, or the softer passages are made louder, or both. See `Recording`.

Mastering.

The process of finalizing audio for a specific medium, such as the Web or audio CD. See above.