Antares AVP1 Hardware user manual

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Pitches are often described relative to one another as intervals, or ratios of
frequency. For example, two pitches are said to be one octave apart if
their frequencies differ by a factor of two. Pitch ratios are measured in
units called cents. There are 1200 cents per octave. For example, two tones
that are 2400 cents apart are two octaves apart. The traditional twelve-
tone Equal Tempered Scale that is used (or rather approximated) in 99.9%
of all Western tonal music consists of tones that are, by...

6
How Auto-Tune corrects pitch
Auto-Tune works by continuously tracking the pitch of an input sound and
comparing it to a user-defined scale. The scale tone closest to the input is
continuously identified. If the input pitch exactly matches the scale tone,
no correction is applied. If the input pitch varies from the desired scale
pitch, an output pitch is generated which is closer to the scale tone than
the input pitch. (The exact amount of correction is controlled by the Speed
parameter, described below...

7
An example
As an example, consider this before-and-after graphic representation of
the pitch of a vocal phrase that contains both vibrato and expressive
gestures.
In the original performance, we can see that although the final note
should be centered around D, the vocalist allowed the tail of the note to
fall nearly three semitones flat. The “after” plot is the result of passing
this phrase through the AVP set to a D Major Scale (with C# and B set to
”Blank”) and a Speed setting of 10. That Speed...

8
With the AVP, you can record each track through a model of the type of
mic that will best produce that ideal sound you’re looking for. Or use it in
live performance to get the sound of mics you’d never consider using on
stage. You can even use it during mixdown to effectively change the mic
on an already recorded track. And for that final touch of perfection, you
can even add some tasty tube saturation.
About the technology
The models employed by the AVP are not derived from theoretical consid-...

9
Why reduce the dynamic range? Consider the problem of mixing the vocal
in a contemporary rock or pop song. Typically, pop music has a relatively
consistent level of loudness. If an uncompressed vocal track is added to a
typical pop mix, loudly sung words or syllables would jump out of the mix,
while quieter phrases would be buried beneath the instrumental texture.
This is because the difference between the loudest and softest sounds in
the vocal - its dynamic range - is very large. This same problem...

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Limiting
Examine the 99:1 curve in the above graph. This setting reduces all sounds
above the threshold to the same loudness. This is called limiting. Limiting
is usually employed to allow a dynamic signal to be recorded at a maxi-
mum level with no risk that transient peaks will result in overload. In this
application, the threshold setting (usually set relatively high) determines
the extent to which the peaks will be limited.
Dynamic Expansion and Gating
Sometimes, it is desirable to increase the...

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When expanders use ratios higher than 1:10, sounds below the threshold
are faded out very rapidly. This effect is called gating and can sound very
abrupt. Adjusting the gate ratio can smooth out the abrupt change. The
graph below shows the input/output curve for a typical gate.
OUTPUT
LEVEL
INPUT LEVELLOUDER
LOUDER
THRESHOLD
1 TO 2 EXPANSION RATIO
1 TO 1 RATIO
OUTPUT
LEVEL
INPUT LEVELLOUDER
LOUDER
THRESHOLD
1 TO 99 EXPANSION RATIO
1 TO 1 RATIO 

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Sounds that are louder than the threshold get “through the gate” un-
changed. Sounds that are below the threshold are not heard. Gates can be
used to great effect in processing drum tracks where sounds from the
other instruments in the drum set leak through the mike of the instru-
ment being recorded. Gates are also used frequently to “gate off” a
reverb tail or the ringing from an insufficiently damped drum head.
Compression and Expansion Combined
The AVP allows you to use both compression and...

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Hard Knee/Soft Knee
The graphs shown above have what are described as “hard knees” in their
gain curves. This means that as the signal passes through the threshold,
the gain reduction it receives will begin abruptly. In settings where the
compression or expansion ratios have high values, the abrupt change can
be heard and often sounds artificial.
To make it possible to create settings where the dynamic effects are more
natural sounding, the AVP incorporates a Knee control which allows you
to soften...

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Attack and Release Times
The attack time of a compressor is how long it takes for the compressor to
react once the input level has met or exceeded the threshold level. With a
fast attack time, the signal is brought under control almost immediately,
whereas a slower attack time will allow the start of a transient or a
percussive sound to pass through uncompressed before the processor
begins to react.
For sounds without percussive attacks (voices, synth pads, etc.), a fairly
short attack time is usually...