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Mastering defined:
A
fine tuning technical and sometimes artistic process that is applied to
a final studio mix. No matter if your audio is planned for CD
replication, cassette duplication, is to be included in CDRom authoring
or published to the World Wide Web, it must be mastered to take full
advantage of the media in which it is to be released. Mastering is the
last step before replication and distribution, therefore your last chance to correct any
deficiencies or accesses in your program material. Projects that
contain material from various sessions, overdubs, musicians, engineers,
producers... sometimes in and of itself can lead to a lack of perceived
consistency of your project. Mastering can help fused all these
elements into a cohesive sounding package.
In Short: Mastering
is meant to correct audio deficiencies and accesses in regards to;
audio fidelity, noise reduction, tonal balance, stereo imaging, fade
ins and fade outs, relative volume level from track to track, track
sequencing order of final master, and overall consistency of the
program material and package...
These are the main
concerns of the mastering engineer that must be dealt with during the
mastering process [but certainly are not limited to these issues].
Equalization (EQ), compression, de-essing, expansion, noise reduction,
frequency analysis [FFT], stereo spectral enhancement, ambience
enhancement [which can help fuse overdubs that where done in different
studios with different ambience characteristics]. These are just some
of the tools and techniques that the mastering engineer can provide to
help your project achieve the necessary audio fidelity heard on
national commercial recordings.
Tools and Techniques:
Truncation:
Eliminate noise prior to the start of your program material so that the
listeners first thoughts are about your music not your noise. Clean up
fades so that they are smooth with no "drop off" feeling on the final
tail of the fade.
Noise Reduction/Removal:
Use the same noise reduction process that George Martin used to restore
and release John Lennon's "Free As A Bird" on the Beatles Anthology
CD/Video. If restoration is the job there is no better tool.
Equalization:
Tighten the relationship between tracks. Smooth out the low end and add
punch and power. Curb the brittle highs that can occur in the digital
domain and add softness to the upper end.
Frequency Dependent Compression:
Excessive low end at 100hz? Sibilance on the vocal performance at 8khz?
Via frequency dependent compression many of the ill effects of these
excesses can be controlled and/or eliminated.
Program Compression:
Prevent some passages of a program from being too loud while others too
quiet. This may be necessary if proper compression was not used on the
final mix down.
Stereo Enhancement:
Widen the stereo field of your material beyond the physical boundaries
of speaker placement, all while keeping mono compatibility for
broadcast and the Internet playback.
Ambience Enhancement:
Sometimes when multiple sessions, overdubs and/or studios are used,
adding a common ambience to the mix can help adhere these performances
together giving the perception that a common recording space was
utilized. Especially helpful for Rock and Roll where bands count on a
"Live Feel" , that multiple overdubs, sessions and an inadequate common
tracking space tend to lack. Put the "Live Feel" back into your mixes.
Brick Wall Limiting w/UV22, POWr or UV22:
Increase the output of your final master 4-6db over digital "0" without
any change to the overall tonal quality and without adding unwanted
artifacts. Sample: normalization CAN NOT increase the gain output of
your program material over digital "0".
How Normalization Works:
Compact disc digital audio consists of 44,100 samples per second. Lets
put that in prospective, that's 2,646,000 samples per minute with a
typical 3 minute song consisting of 7,938,000 samples. Now ,
normalization does nothing more than look for the one sample which is
closest to or has reached digital "0". If just one sample out of the
7,938,000 samples in your song happens to reach "0" than there will be
no gain increase, for anything over digital "0" will cause digital
distortion and not be accepted at the replication plant because the
Sony/Phillips protocol does not allow for "digital overs".
Normalization Is Of No Practical Use In Mastering And Therefore Should
Be Avoided! But with the proper digital tools, once a peak relationship
has been established to digital "0" for a given track, a smart look
ahead of all the samples in the program can take place. Then by using
limiting w/IDR, that one sample that has reached digital "0" [as in the
example above], can be pushed back and the overall output gain of the
entire program content can be increased 4-6db over digital "0". UV22,
POWr & IDR : Are patented process' where by the perceived bit rate
of a 16 bit audio file is increase to 18-20 bits. e.g. An 8 bit word is
= 256 steps, 16 bit word is 256 x 256 = 65,536 steps [obviously a much
greater resolution], a 20 bit word is 65,536 x 16 = 1, 048,576 steps, a
24 bit word is 1,048,576 x 16 = 16,777,216 [now you know why everyone
is anticipating the coming DVD format, which will allow for 20 and 24
bit audio, as well as digital video. graphics...
Relative Volume:
Even after the process of increasing program output gain, some tracks
may still sound louder even if the peak levels are consistent. This
could be due to low frequency content and/or compression during the mix
down sessions, etc.. Relative volumes of each track in relationship to
one another must be adjusted manually to insure all tracks have the
same relative volume.
PQ Encoding:
Of the 8 channels of subcode data that are interleaved with digital
audio data, only the P & Q channels are used by "Red Book" CD
players. The P channel tells the CD player which track is playing and
which track is not, while the Q channel describes track and disc
running times, copy protection, emphasis flags, disc catalog code and
song ISRC codes. You must have a PQ encoded master if you final product
will be Compact Disc. We recommend PQ encoding ALL masters so that
future product orders will not be limited to analog media.
Pre Mastering Requirements:
MASTERING/EDITING
- Master tape should be edited and ready for mastering, if there is the
need for additional editing the master tape must include an EDL, [be
sure to note any information the edit engineer may need to perform your
edits]. The tape box should be properly labeled including all titles in
proper sequence and times of selections. Also indicate total time. Be
sure to include along with the master tape any special instructions, or
indicate that it is to be transferred exactly as is. If no instructions
are included with the tape, our mastering engineer will do whatever he
thinks necessary to make the best sounding compact disc and/or cassette
possible. If complex adjustments or restoration is necessary, there
will be an additional mastering charge of $60.00 per hour and are
billed in quarter-hour segments.
Suggestions:
When
the mastering engineer receives your master tape or disc, the only knowledge he
will have of your project is the information provided. Any information
you supply is useful in obtaining the best possible product, no amount
of information is too much.
Always give a all phone
numbers where you can be reached. The engineer may start work on your
project and need to communicate with you. If you cannot be reached,
your project may be delayed until contact is made.
A
master log with song sequence and times should be included with
each master tape or disc. False starts, errant ID's or any abnormality should
be noted, this information is necessary for the mastering engineer to
complete your order correctly and efficiently.
When test tapes or CDRs
are sent for your approval do not
delay in your approval. Quick approval is necessary to ensure final
delivery within the appropriate deadlines.
If there are
discrepancies between what you delivered for mastering and what you receive as a test CDR, remember this is the
purpose of a "test". Call the mastering facility with any concerns you have. They will generally correct and/or adjust for your full approval before
manufacturing.
INFORMATION PROVIDED BY: SOWETO PRODUCTIONS - www.soweto.com
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