What Is A Broadcast Quality Recording? Part 5: Mastering Basics
By Jerry Flattum - 02/03/2005 - 06:05 AM EST
What Is A Broadcast Quality Recording?
Part 5: Mastering Basics
Regardless of how elaborate a home studio, mixers and masters are still competing with the best. And, one of the best is Bob Ludwig. A quick scan of Ludwig’s website reveals what home studios are up against: Gateway Mastering.
At the site is a sampling of the equipment used for high end mastering: Gateway Mastering - Equipment.
Taken from the site: “Unfortunately, music can never sound as good on a CD as it does in the studio. DVD and SACD are changing that. The capabilities of the DVD or SACD allow the consumer to hear what we hear.”
The above quote is a clue to the possibilities of making even better recordings in a home studio environment.
A list of mastering formats is found at this page: Gateway Mastering - Formats.
Studio equipment and computer manufacturers will try and convince musicians and home studio engineers they can produce a finished product in a living room sitting in their underwear. Meanwhile, there are studio engineers with years of experience, using expensive and custom designed equipment in state--of-the-art studios with unlimited budgets.
Basic Recording/Mixing Equipment
Whether analog or digital, the list of basic recording/mixing equipment is pretty simple.
-- A studio
-- A mixing console (board)
-- Monitors (Speakers)
-- FX (Effects)
-- Tape deck or CD Player
-- Computer with Sound Card
-- Recording/Sequencing Software
-- MIDI Interface
-- Digital recording/mixing software
-- Computer soundcards
Things start to get complex when numerous manufacturers offer a wide range of models in any of the equipment areas. Quality is generally dictated by price.
What Is A Recording?
Recordings are approximations of reality and they are enhancements of reality. With digital technology, it became a question of capturing reality without interference from mechanical defects: tape speeds, tape materials, or what happens when recordings are replicated (producing replications that rival the master). Analog playback devices suffered similar mechanical problems, like worn-out needles or wobbly turntables. Vinyl records were easily subject to scratches, gouges and weather conditions (Actually, CDs require the same care against damaged surfaces).
The three phases of recording are recording the tracks, mixdown, and mastering.
A recording is the result of the sound of the instrument(s), how those instruments are played, how they are “mixed,” and how the recording is ultimately “mastered.” What is being recorded is a combination of song, performance, sound, voice, musical instrument, arrangement, f/x and mix.
Techniques vary dramatically in terms of recording analog signals vs. digital signals. Recording live instruments is very dependent on the type of microphone used and it’s placement, as well as the studio itself (acoustics). Plus, musicians make noise when they play; singers breath and pop their “p’s,” guitarists slide their fingers along fretboards, percussionists play dynamically. The sheer act of plugging a guitar into an amp carries with it all kinds of possible hums and buzzes, depending on the quality of equipment used.
By contrast, the signal from a digital sound-producing unit to a digital recording device remains almost pristine. But, the crystal clarity gained when recording samples, loops or fonts can be a trade off for the warmth and “human feel” of analog. Often times mastering digital recordings is more complicated when using f/x processing to add lost warmth, dynamics and feel. Recording is the subjective experience of listening, and some recordphiles still prefer the warmth of vinyl to digital recordings.
What Is Premastering?
Premastering is whatever you do to prepare your mix for the final master. It’s like making a list and checking it twice. All noise has been reduced to a minimum. All levels are maximized. Everything has its “space” in the stereo field (or surround field). Dynamics are crisp and clear.
Premastering is also a bridge between mixing and mastering. There is much overlap. Something already done in the mix may be redone or further enhanced in mastering.
A true master for a Compact Disc is called the Glass master, which is etched on a laser cutter at the pressing plant. In fact, the Glass Master is destroyed during the production process. The only thing permanent is the stamper, a round metal form that can be used to press thousands of CDs before it’s replaced. There are two intermediate steps (the father and the mother) before creating the stampers that press your CDs. The “premaster” might be an Exabyte DDP tape, a CDR (recordable CD), or a PCM-1630 tape, but it will often be called a master, because no further enhancement is needed. Ideally, the replications will be exact copies of the master.
What Is Mastering?
Mastering is the fine-tuning involved in preparing a recording for broadcast (radio, TV, Film, Internet) and CD/DVD distribution. Mastering is—in the simplest terms—is taking a mix and preparing it for replication. It’s a process of taking a mix—usually in the form of a 2-track stereo mixed down file and adding the final polish. Generally, this can involve equalization, compression, harmonic excitation, maximizing loudness and more. Actually, these “sweetening” aspects are more about “pre-mastering” than mastering.
In the making of a CD, mastering is more of a process of establishing consistency for the 10 or so “cuts” in terms of volume levels and how each song sounds when played after another.
Other mastering considerations are such things as preparing the package (CD layout), file conversion, and the “glass master” -- the actual master used for replication. Variations in preparing the master depend on the intended delivery format. In the case of a CD it might mean converting to 16-bit/44.1kHz audio through “resampling and dithering,” and setting track indexes, track gaps, PQ codes, and other CD specific markings.
Terminology and Process
Here’s a list of terms and processes in random order.
· Placing tracks in a desired order
· Leaving 2-second gaps between tracks
· Applying noise reduction to eliminate hum and hiss
· Do A/B testing (Comparing a mix with compression to one without compression)
· Normalizing (setting volume peak levels) tracks in an individual song
· Normalizing all the cuts on a CD
· Making sure there are no jumps in bass, treble, midrange, volume or pan
· Applying compression -- smoothing out highs and lows
· Using f/x to bring out dynamics
· Providing each instrument its own “space”
· Cleaning up intros and fades (endings)
· Matching volume and dynamic levels for all tracks
· Editing and signal processing to optimize timbre, clarity, smoothness and impact
· Maximizing stereo or surround-sound balance and field
· Creating the package (jewel case, inserts, lyrics, etc.)
In the digital domain, using sampled sounds, noise is not an issue, unless there is something radically wrong with your sound card or computer. By watching your volume level meters, you can be relatively safe in terms of not being too loud or soft.
Fix It In The Mix
Some engineers believe audio processing essentially ends at mixdown. As long as you recorded your tracks right and the mix is good, nothing further needs to be done. It's obvious when a recording has hisses, pops and other noises, that it needs to be further processed to remove unwanted sounds. Such noise is created using cheap recording devices, microphones, and poor recording techniques. But in the digital domain, using sampled sounds, noise is not an issue, unless there is something radically wrong with a sound card or computer.
So, one component of mastering is "fixing" problems in recording. A guitarist can hit a wrong chord or hit it too loud causing a volume swell. A decision both artist and engineer will need to make is whether to record the track again or "fix" it in the mix.
A sloppy performance or a poorly recorded performance can be fixed in the mix, to a degree. Not even the best mixers and mastering engineers in the world can improve on a bad singer or bad musicianship.
Then again, a great vocal or instrumental performance can be ruined by a bad recording or lost in a bad mixdown. Mastering is finding a balance for all the tracks, so they sound good together, at the right volume, without loss of dynamics, on the same CD. A mixdown is where individual tracks are combined and mixed down to a stereo two-track.
The more complicated the arrangement, the more complicated the mix.
The better the music the easier it is to mix.
However, mixing is often a question of re-recording tracks vs. fixing in the mix.
Many mastering engineers claim if the recording and final mix is poor, there's not much they can do to fix it. No doubt there are engineers who feel they can fix anything, and probably can, given the staggering array of processing equipment available.
How a recording is mastered can affect long-term sales. If compression is used to make the recording too loud, it can produce ear fatigue. The listener will not listen to the recording over and over.
How Does It Sound?
Recordings face the same subjective criteria in describing quality, as do songs and artists. It’s not loud enough. It’s wimpy. It lacks sparkle. It’s just not exciting. The vocals sound thin. The guitar is harsh. The low end is boomy. The high-end lacks depth. Fixing these problems is possible through various effects (f/x). But all the technical gadgets in the world can’t fix a bad song or performance.
Things happen once you start adding tracks. It’s the nature of combining different sounds, whether it’s analog or digital. The more tracks, or, the more complex the arrangement, the greater chance there is in terms of loss of dynamics.
A Richenbacker bass, for instance, has a distinct sound, as does an acoustic bass or any other kind of bass for that matter. But once the bass drum and a low-end synth sound are added, those subtleties that distinguish a particular sound or instrument start to get lost. The problem is not the instrument or even the equipment used to capture the recording. In fact, the performance may be excellent. The song is potentially a hit. It’s just the nature of mixing sound with sound. Mastering provides the solution.
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