Antares AutoTune Live user manual

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To take maximum ad\bantage of t\fe power of Auto-Tune Li\be’s pitc\f cor-
rection functions, you s\fould \fa\be a basic understanding of pitc\f and \fow 
Auto-Tune Li\be functions to correct pitc\f errors. T\fis c\fapter presents basic 
terminology and introduces Auto-Tune Li\be’s operating paradigm, gi\bing 
you t\fe background you need to use it effecti\bely.
A little bit abo\ft \Apitch 
Pitc\f is traditionally associated wit\f our perception of t\fe “\fig\fness” or 
“lowness” of a particular sound.  our perception of pitc\f ranges from t\fe 
\bery general (t\fe \fig\f pitc\f of \fissing steam, t\fe low pitc\f of t\fe rumble of 
Godzilla’s enormous footsteps as \fe stomps \fis way t\froug\f Tokyo) to t\fe 
\bery specific (t\fe exact pitc\f of a solo singer or \biolinist). T\fere is, of course, 
a wide range of \bariation in t\fe middle. A symp\fony orc\festra playing a 
scale in unison, for example, results in an extremely complex wa\beform, yet 
you are still able to easily sense t\fe pitc\f.
T\fe \bocalists and t\fe solo instruments t\fat Auto-Tune Li\be is designed to 
process \fa\be a \bery clearly defined quality of pitc\f. T\fe sound generating 
mec\fanism of t\fese sources is a \bibrating element (\bocal c\fords, a string, 
an air column, etc.). T\fe sound t\fat is t\fus generated can be grap\fically 
represented as a wa\beform (a grap\f of t\fe sound’s pressure o\ber time) 
t\fat is periodic. T\fis means t\fat eac\f cycle of wa\beform repeats itself fairly 
exactly, as in t\fe periodic wa\beform s\fown in t\fe diagram below:
Because of its periodic nature, t\fis sound’s pitc\f can be easily identified and 
processed by Auto-Tune Li\be.
o t\fer sounds are more complex. T\fis wa\beform:
is of a \biolin section playing a single note in unison.  our ears still sense a 
specific pitc\f, but t\fe wa\beform does not repeat itself. T\fis wa\beform is 
a summation of a number of indi\bidually periodic \biolins. T\fe summation 
is non-periodic because t\fe indi\bidual \biolins are slig\ftly out of tune wit\f 
respect to one anot\fer. Because of t\fis lack of periodicity, Auto-Tune Li\be 
would not be able to process t\fis sound. 
						

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Some pitch termino\Alogy
T\fe pitc\f of a periodic wa\beform is defined as t\fe number of times t\fe 
periodic element repeats in one second. T\fis is measured in Hertz (abbre\bi-
ated Hz.). For example, t\fe pitc\f of A4 (t\fe A abo\be middle C on a piano) is 
traditionally 440Hz (alt\foug\f t\fat standard \baries by a few Hz. in \barious 
parts of t\fe world). 
Pitc\fes are often described relati\be to one anot\fer as inter\bals, or ratios 
of frequency. For example, two pitc\fes are said to be one octa\be apart if 
t\feir frequencies differ by a factor of two. Pitc\f ratios are measured in units 
called cents. T\fere are 1200 cents per octa\be. For example, two tones t\fat 
are 2400 cents apart are two octa\bes apart. T\fe traditional twel\be-tone 
e qual Tempered Scale t\fat is used (or rat\fer approximated) in 99.9% of 
all Western tonal music consists of tones t\fat are, by definition, 100 cents 
apart. T\fis inter\bal of 100 cents is called a semitone. 
T\fe twel\be equally-spaced tones of t\fe  equal Tempered Scale \fappen to 
contain a number of inter\bals t\fat approximate integer ratios in pitc\f. T\fe 
following table s\fows t\fese approximations: 
INT\bRVAL   C\bNTS  N\bARBY   RATIO IN
   RATIO  C\bNTS 
minor second  100  16/15  111.75
major second  200  9/8  203.91
minor t\fird  300  6/5  315.64
major t\fird  400  5/3  86.31 
perfect fourt\f  500  4/3  498.04 
tritone   600 
perfect fift\f  700  3/2  701.65 
minor sixt\f  800  8/   813.69 
major sixt\f  900  5/3  884.36 
minor se\bent\f  1000   16/9  996.09 
major se\bent\f  1100  15/8  1088.27
octa\be   1200  2  1200.00 
As you can see, t\fe inter\bals in t\fe  equal Tempered Scale are N oT equal 
to t\fe \farmonious integer ratios. Rat\fer, t\fe  equal Tempered Scale is a 
compromise. It became widely used because once a \farpsic\ford or piano is 
tuned to t\fat scale, any composition in any key could be played and no one 
c\ford would sound better or worse t\fan t\fat same c\ford in anot\fer key.  
						

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How A\fto-T\fne Live detects pitch
In order for Auto-Tune Li\be to automatically correct pitc\f, it must first 
detect t\fe pitc\f of t\fe input sound. Calculating t\fe pitc\f of a periodic 
wa\beform is a straig\ftforward process. Simply measure t\fe time between 
repetitions of t\fe wa\beform. Di\bide t\fis time into one, and you \fa\be 
t\fe frequency in Hertz. Auto-Tune Li\be does exactly t\fis: It looks for a 
periodically repeating wa\beform and calculates t\fe time inter\bal between 
repetitions.
T\fe pitc\f detection algorit\fm in Auto-Tune Li\be is \birtually instantaneous. 
It can recognize t\fe repetition in a periodic sound wit\fin a few cycles. T\fis 
usually occurs before t\fe sound \fas sufficient amplitude to be \feard. Used 
in combination wit\f an extremely slig\ft processing delay, t\fe output pitc\f 
can be detected and corrected wit\fout artifacts in a seamless and continu-
ous fas\fion. 
Auto-Tune Li\be was designed to detect and correct pitc\fes up to t\fe pitc\f 
C6. (If t\fe input pitc\f is \fig\fer t\fan C6, Auto-Tune Li\be will occasionally 
interpret t\fe pitc\f an octa\be lower. T\fis is because it interprets a two cycle 
repetition as a one cycle repetition.)  on t\fe low end, Auto-Tune Li\be will 
detect pitc\fes as low as 25Hz (w\fen t\fe Bass Input Type is selected). T\fis 
range of pitc\fes allows intonation correction to be performed on \birtually 
all \bocals and instruments.
o f course, Auto-Tune Li\be will not detect pitc\f w\fen t\fe input wa\beform 
is not periodic. As demonstrated abo\be, Auto-Tune Li\be will fail to tune up 
e\ben a unison \biolin section. But t\fis can also occasionally be a problem 
wit\f solo \boice and solo instruments as well. Consider, for example, an 
exceptionally breat\fy \boice, or a \boice recorded in an una\boidably noisy 
en\bironment. T\fe added signal is non-periodic, and Auto-Tune Li\be will 
\fa\be difficulty determining t\fe pitc\f of t\fe composite (\boice + noise) 
sound. Luckily, t\fere is a control (t\fe Tracking control, discussed in C\fapter 
3) t\fat will let Auto-Tune Li\be be a bit more casual about w\fat it considers 
“periodic.”  experimenting wit\f t\fis setting will often allow Auto-Tune Li\be 
to track e\ben noisy signals.
A NOT\b: The abo\fe des\bript\Lion has been in pr\Letty mu\bh e\fery Auto\L-Tune 
manual sin\be the beginning. W\Lhile it is still d\Lefinitely true in th\Le general 
\base, it must be no\Lted that Auto-Tune E\fo did a mu\bh \Lbetter job than an\Ly 
prior \fersion of Au\Lto-Tune with borderline troublesome material\L and Auto-
Tune Li\fe (as well as Auto-Tune 7) does e\fen better y\Let. 
						

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How A\fto-T\fne Live corrects pitch
Auto-Tune Li\be works by continuously tracking t\fe pitc\f of an input sound 
and comparing it to a user-defined scale. T\fe scale tone closest to t\fe input 
is continuously identified. If t\fe input pitc\f exactly matc\fes t\fe scale tone, 
no correction is applied. If t\fe input pitc\f \baries from t\fe desired scale tone, 
an output pitc\f is generated w\fic\f is closer to t\fe scale tone t\fan t\fe input 
pitc\f. (T\fe exact amount of correction is controlled by t\fe Retune Speed 
and Humanize settings, described below and in C\fapter 3.) 
Scales 
T\fe \feart of Auto-Tune Li\be pitc\f correction is t\fe Scale. Auto-Tune Li\be 
lets you c\foose from major, minor, c\fromatic or 26 \fistorical, et\fnic and 
micro-tonal scales. Indi\bidual scale notes can be bypassed, resulting in 
no pitc\f correction w\fen t\fe input is near t\fose notes. Indi\bidual scale 
notes can also be remo\bed, allowing a wider range of pitc\f correction for 
neig\fboring pitc\fes. T\fe scale can be detuned, allowing pitc\f correction to 
any pitc\f center. 
For added flexibility, you can also select t\fe target pitc\fes in real time \bia 
MIDI from a MIDI keyboard or a pre-recorded sequencer track. 
Ret\fne Speed 
Auto-Tune Li\be also gi\bes you control o\ber \fow rapidly, in time, t\fe pitc\f 
adjustment is made toward t\fe scale tone. T\fis is set wit\f t\fe Retune Speed 
control (see C\fapter 3 for more details). 
Fast Speed settings are appropriate for s\fort duration notes and for 
mec\fanical instruments, like oboe or clarinet, w\fose pitc\f typically c\fanges 
almost instantly. A fast enoug\f setting will also minimize or completely 
remo\be a \bibrato, as well as produce t\fe iconic Auto-Tune vocal  effect. 
Slow Speed settings, on t\fe ot\fer \fand, are appropriate for longer notes 
w\fere you want expressi\be pitc\f gestures (like \bibrato) to come t\froug\f at 
t\fe output and for \bocal and instrumental styles t\fat are typified by gradual 
slides (portamento) between pitc\fes. An appropriately selected slow setting 
can lea\be expressi\be gestures intact w\file mo\bing t\fe a\berage pitc\f to t\fe 
correct tonal center. 
Vibrato 
Auto-Tune Li\be allows real-time adjustment of t\fe dept\f of any natural 
\bibrato present in t\fe input. 
Auto-Tune Li\be can also add a \bibrato to an input t\fat does not naturally 
ex\fibit one. You can program t\fe \bibrato rate along wit\f indi\bidual \bibrato  
						

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dept\fs for pitc\f, amplitude (loudness) and formant (resonant frequencies). 
You can also specify delayed \bibrato wit\f independently programmable 
onset delay and onset rate. 
By combining a fast Retune Speed setting wit\f Auto-Tune Li\be’s vibrato 
settings, you can e\ben remo\be a performer’s own \bibrato and replace it 
wit\f Auto-Tune Li\be’s programmed \bibrato, all in real time. Also, unusual 
combinations of  vibrato Wa\beform, Rate and Dept\f settings can be used 
for some interesting special effects. 
An example of A\fto-T\fne Live pitch correction 
As an example, consider t\fis before-and   -after grap\fic representation of t\fe 
pitc\f of a \bocal p\frase t\fat contains bot\f \bibrato and expressi\be gestures. 
In t\fe original performance, we can see t\fat alt\foug\f t\fe final note s\fould 
be centered around D, t\fe \bocalist allowed t\fe tail of t\fe note to fall nearly 
t\free semitones flat. T\fe “after” plot is t\fe result of passing t\fis p\frase 
t\froug\f Auto-Tune Li\be programmed to a D Major Scale (wit\f C# and B set 
to ”Remo\be”) and a Retune Speed setting of 25. T\fat Retune Speed causes 
t\fe pitc\f center to be mo\bed to D, w\file still retaining t\fe \bibrato and 
expressi\be gestures. (Setting C# and B to ”Remo\be” is necessary to keep 
Auto-Tune Li\be from trying to correct t\fe seriously flat tail of t\fe last note 
to t\fose pitc\fes. See C\fapter 3 for more details.) 
1 0.0 10.5 11.0
D3
B2
ORIGINAL
PERFOR MANCE
CO
RRE CTED BY  
AU TO-TUNE LI\fE
C# 3 
						

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Formant Correction and Throat Modeling
Formant Correction
A sound’s “formants” are t\fe combined acoustic resonances t\fat result 
from t\fe p\fysical structure of w\fate\ber is producing t\fe sound. 
In t\fe case of a \fuman \boice, air from your lungs is forced t\froug\f your 
\bocal c\fords, causing t\fem to \bibrate. From t\fere, t\fe \boice is propagated 
t\froug\f t\fe t\froat, t\fe mout\f and out t\froug\f t\fe lips. It is t\fe s\fape of 
t\fese structures t\fat create t\fe resonant c\faracteristics t\fat define your 
unique \bocal identity.
W\fen a \bocal is pitc\f-s\fifted by large inter\bals wit\fout formant correction, 
not only is t\fe pitc\f of sung notes s\fifted, but t\fe formants are s\fifted 
as well. T\fe resulting effect is not just of a person singing \fig\fer or lower 
notes, but of a person w\fo is literally growing or s\frinking (depending on 
t\fe direction of t\fe s\fift).  W\file t\fis can be useful for producing singing 
c\fipmunks, it typically does not produce realistic \bocals w\fen s\fifted more 
t\fan a semitone or two.
engaging Auto-Tune Li\be’s Formant Correction pre\bents t\fe s\fifting of 
a \boice’s resonant frequencies to ensure t\fat its \bocal c\faracteristics are 
preser\bed o\ber t\fe pitc\f s\fift range.
AN IMPORTANT NOT\b: O\fer the \fery small\L inter\fals usually \Lasso\biated 
with basi\b pit\bh \borre\btion, formant shifting is \Lessentially inaudib\Lle and 
Auto-Tune’s \blassi\b pit\bh adju\Lstment te\bhnology s\Ltill pro\fides the optimum \L
results. Formant Corre\btion is designed \Lto be used on tra\bks where notes are 
shifted by larger inter\fals.
Throat Modeling
As mentioned abo\be, t\fe s\fape of a singer’s t\froat is a prime contributor to 
t\feir \bocal c\faracter. Auto-Tune Li\be’s T\froat Lengt\f control lets you use 
Antares’ unique t\froat modeling tec\fnology to modify a \boice’s c\faracter 
by passing it t\froug\f a precise p\fysical model of t\fe \fuman \bocal tract. 
						

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Latency
Due to t\fe nature of \fow Auto-Tune works, along wit\f differences in 
t\fe \barious \fosts, w\fo all add t\feir own bit of latency during tracking, 
it’s impossible to state an absolute Auto-Tune Li\be latency specification. 
Howe\ber, in our tests of Auto-Tune Li\be in major \fosts, latency was 
consistently undetectable w\fen tracking li\be wit\f \bocals. 
For t\fe tec\fnically curious, t\fe maximum in\ferent latency of Auto-Tune 
Li\be itself, distinct from any contribution by t\fe \fost, is \bariable wit\f t\fe 
frequency of t\fe audio being detected and range of t\fe correction. As an 
example, w\fen correcting to a target pitc\f of A 440Hz, Auto-Tune Li\be’s 
latency can \bary from a only a few samples to a maximum of around 100 
samples (less t\fan 2.3ms). Again, t\fis is separate from t\fe in\ferent latency 
of your \fost. 
For all practical purposes, Auto-Tune Li\be’s response is instantaneous. 
Howe\ber, if you’re t\fe sort w\fo wants to know t\fat you’re getting t\fe 
absolute minimum total latency from Auto-Tune Li\be and your \fost, you 
can reduce your \fost’s \fardware buffer size to t\fe smallest size t\fat still 
results in acceptable audio performance.  
						

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T
Chapter 3: Auto-Tune Live Controls
T\fis c\fapter is a reference for all of t\fe controls used in t\fe Auto-Tune 
Li\be interface. How t\fese controls are used toget\fer for pitc\f correction is 
demonstrated in C\fapter 4, Auto-Tune Li\be Tutorials. 
Contin\fo\fs Controls
Auto-Tune Li\be’s continuous controls are represented grap\fically as \birtual 
knobs. Depending on your preference, you can control knobs by linear 
or radial mouse mo\bement. Set your preference in t\fe options dialog 
described below. 
Double-clicking on a knob will return it to its default \balue. In some \fost 
applications, Command (Mac)/Control (PC) clicking on a knob will also reset 
it to default (see your \fost application manual for details). 
						

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Inp\ft Type
As a result of Antares’ researc\f into t\fe unique c\faracteristics of \barious 
types of audio signals, Auto-Tune Li\be offers a selection of optimized pro-
cessing algorit\fms for t\fe most commonly pitc\f-corrected inputs. C\foices 
include Soprano  voice, Alto/Tenor  voice, Low Male  voice, Instrument, and 
Bass Instrument. Matc\fing t\fe appropriate algorit\fm to t\fe input results in 
e\ben faster and more accurate pitc\f detection and correction.
To select t\fe desired Input Type, click on t\fe Input Type pop-up and t\fen 
select t\fe desired type from t\fe pop-up list.
NOT\b: Choosing the wrong Input Type (or just forgetting to set it \Lat all) 
\ban result in \bompromised performan\be. Pay attention.
ANOTH\bR NOT\b: When any Input Type other than Bass\L Instrument is 
sele\bted, Auto-Tune Li\fe is reliably able to det\Le\bt pit\bhes down to\L A1 
(55Hz). Sele\bting Bass I\Lnstrument lowers t\Lhe lowest dete\btabl\Le frequen\by 
by about one o\bta\fe \Lto 25Hz. Sin\be the lowest E str\Ling on a bass guit\Lar is 
approximately 41Hz, Bass Instrument (as its name so abl\Ly implies) allows 
you to apply pit\bh \b\Lorre\btion to those pes\Lky fretless bass lines \Las well 
as other low bass \Lrange instruments. \LHowe\fer, when Bass Instrument is 
sele\bted, pit\bhes a\Lbo\fe A4 may be in\borre\btly tuned, so be \Lsure to sele\bt 
Bass Instrument only when\L \borre\bting bass range tra\bks.
Tracking
In order to accurately identify t\fe pitc\f of t\fe input, Auto-Tune Li\be 
requires a periodically repeating wa\beform, c\faracteristic of a \boice or solo 
instrument. T\fe Tracking control determines \fow muc\f \bariation is allowed 
in t\fe incoming wa\beform for Auto-Tune Li\be to still consider it periodic.
If you are working wit\f a well-isolated solo signal (e.g., tracking in a studio 
or off of a multi   track master) you can typically set t\fe Tracking control to 50 
and forget it.
If, on t\fe ot\fer \fand, your signal is noisy or not well-isolated (as mig\ft 
be more common in a li\be performance situation) or you are dealing 
wit\f a particularly breat\fy or guttural \boice, it may be necessary to allow 
more signal \bariation (\fig\fer Tracking numbers). Howe\ber, under t\fese 
circumstances tracking is not guaranteed and a too “relaxed” setting may 
introduce distortion and popping. 
						

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Select Pitch Reference
Auto-Tune Li\be pro\bides t\fe ability to pitc\f correct 
stereo tracks w\file maintaining t\fe tracks’ p\fase 
co\ference. (Refer to your \fost application’s manual 
for instructions on assigning a plug-in to a stereo 
track.) Click t\fe appropriate button to select w\fic\f 
of t\fe two stereo tracks (left or rig\ft) Auto-Tune Li\be will use as a pitc\f 
reference.
NOT\b: If there is a marked differen\be in the two tra\bks, pi\bk the \blean\Lest, 
most isolated tra\bk. For example, if one tra\bk is a \blose mi\b’d \fo\bal while 
the other is mi\b’d from farther away for ambien\be, or is hea\fily pr\Lo\bessed, 
sele\bt the \blose mi\L\b’d tra\bk.
ANOTH\bR NOT\b: Auto-Tune Li\fe will only p\Lit\bh \borre\bt true stereo tra\bks. 
If the se\bond tra\bk (i.e., the tra\bk not sele\bted as\L a pit\bh referen\be) 
is simply an indepe\Lndent unrelated tra\bk, unpredi\btable (and potentially 
unpleasant) sounds \Lmay result. On the othe\Lr hand, something \Linteresting 
might happen. You ne\fer know.
W\fen Auto-Tune Li\be is instantiated on a mono track, t\fis control is inacti\be 
(grayed out).
Key Selection
T\fis control lets you select t\fe key of t\fe track you plan to 
process. 
To select t\fe desired key, click on t\fe Key pop-up and t\fen 
select t\fe desired note from t\fe pop-up list. T\fis determines t\fe pitc\f of 
t\fe first note of t\fe scale according to t\fe standard A3 = 440 Hertz.
Scale Selection
T\fis control is used in combination wit\f t\fe Key 
selection abo\be to define t\fe scale of t\fe track you 
plan to process. 
To select a scale, click on t\fe Scale pop   up and t\fen select t\fe desired scale 
from t\fe pop-up list.
NOT\b: To a\foid ha\fing to deal with s\bales \bontaining those annoying 
double flats, double sharps and notes like Cb, E#, Fb and B#, Auto-Tune 
Li\fe will automati\bally \bhoose the simpler of two enharmoni\bally equi\falent 
s\bales. For example, if you sele\bt Db Major, the Edit S\bale Display will duly 
display the Db Major s\bale. Howe\fer, if you then go to the S\bale sele\btion 
pop-up and sele\bt Minor, the Key will automati\bally be \bhanged to C# and the 
Edit S\bale Display will, in fa\bt, display the mu\bh friendlier C# Minor s\bale.