Antares Infinity user manual

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Linear taper should be used for editing simple periodic waveforms like solo
instruments. Equal power taper should be used when editing complex non-
periodic waveforms like string sections or noise.
THE SYNTHESIS LOOPER REPORT
But how should you set the Sidelobe Width (%) control? How should you
choose MIDI Note or Pitch Detection? The Synthesis Looper Report will
assist you in deciding these issues. Select the Report... button at the bottom
of the Synthesis Looper window. This causes the Synthesis Looper Report
window to be generated: 
						

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This window “belongs” to the soundfile. The data in the window is com-
puted from the soundfile’s loop data at the moment you pressed the
Report... button. You may generate as many reports for a soundfile as you
desire. You may close a report by clicking the “go-away” box in the top
left. If you close a soundfile, all the reports for that soundfile are closed
automatically. You can also press the space bar or the speaker icon in the
palette window to play back the soundfile to which this report belongs.
Remember though, if you modified the soundfile after generating the
report, you will hear the new soundfile.
Fundamental (Hz): The Fundamental (Hz) number is the fundamental
frequency. It is computed using the MIDI Note number or the Pitch detec-
tion method selected when you pressed Report....
Amplitude Spectrum (dB): The Amplitude Spectrum (dB) is the amplitude
(square root of energy) of the loop expressed in Decibels. (Decibels are 20 *
log(value). Every 6 dB is a approximately factor of 2. in amplitude.).
Sidelobe Width (%): The Sidelobe Width (%) graph shows the sidelobe
width computed from the loop as a percentage of the fundamental
frequency. The scale presented is the same as the Sidelobe Width (%) input
graph in the tool. This sidelobe width is computed for the fundamental and
each harmonic as the standard deviation of the energy distribution around
the fundamental or harmonic. It is expressed as a percentage of the
fundamental frequency.
Note that whenever this window is selected and your cursor is over the
Amplitude Spectrum (dB) or Sidelobe Width (%) graphs, you can view the
coordinates of the cursor location on the Status Display Area palette
window.
Log Scale or Linear Scale: At the bottom of the report are radio buttons
labeled Log Scale and Linear Scale. The Log scale allows more resolution at
the low frequencies where the audio content is the most important. The
Linear scale should show an approximate linear increase in sidelobe width
as a function of frequency for ensembles where the instruments are playing
the same notes (with octaves allowed).
The report above is shown using the log scale. The report below is the same
report shown in linear scale. The data is that of a string section. Notice how
the sidelobe width increases approximately linearly with frequency. Use the
linear scale on a report of unprocessed loop data to help you establish
what settings to use in the Synthesis Looper Sidelobe Width (%)graph.
In this graph, you can easily see that the harmonics have frequencies which
are integer multiples of the fundamental frequency. Also, the Normal PDF
distributions in energy show up as narrow concave downward hyperbola
(in Decibels verses linear frequency). Notice how the higher frequency
harmonics are wider. These sidelobe widths are proportional to frequency. 
						

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Note that the above Sidelobe Width (%) graphs were generated using pitch
detection (see the note enclosed in the graph). Pitch detection was used
here because this note was slightly out of tune. You can determine this
because if the MIDI Note were used instead, the graph would appear:
Normally, the sidelobe widths do not exceed 30% unless the expected
harmonic frequency is not aligned to the actual harmonic frequency. This
will happen when the MIDI Note is used for pitch control and the note is
out of tune.
The following graphs show the result of processing the data with the
Retain Noise checkbox clear and checked, respectively. 
						

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Retain Noise unchecked:
Notice how the Sidelobe Width (%) becomes flat above 12k Hz, as was
specified in the Sidelobe Width (%) of the Synthesis Looper tool. 
						

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With Retain Noise checked:
Compare the above graph to the report of the unprocessed data and notice
how the noise floor has been computed to vary with frequency similar to
the initial data. Also notice that the presence of noise causes the Sidelobe
Width (%) computation to be slightly excessive in frequencies where the
noise is nearly the same amplitude as the harmonic.
HOW TO LOOP A SOUND:
First, set the sample’s MIDI Note to as near the correct pitch as possible
using A3 = 440Hz. Second, set the loop points. Note that the Synthesis
Looper will make the loop smaller to the next power of two (approxi-
mately). Open the Synthesis Looper tool. Set the Pitch Control radio to MIDI
Note if you believe your sample should be in tune according to the A3 =
440Hz equal tempered scale. If not, set it to Pitch Detection. 
						

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Next, press the Report... button. On the report, select Log scale and place
your cursor precisely at the fundamental peak. Check that the Fundamental
(Hz): number is within a pixel’s accuracy of the Hertz number on the
floating palette. If it is not, then you are going to have pitch problems. If
you had checked MIDI Note you either specified the wrong note or the
data is not tuned to A3 = 440Hz equal tempered scale. Either re-specify the
note or use Pitch Detection. If you had checked Pitch Detection, then your
MIDI note may be off. The MIDI note was used as an initial guide by the
pitch detection algorithm. If the MIDI note is way off, an incorrect result
would occur. Unfortunately, if you process a short loop (less than 20 cycles),
the Pitch Detection algorithm will not be precise and the result may be
slightly out of tune.
Next, review the Sidelobe width (%) graph. Normally, the sidelobe widths
do not exceed 30% unless the expected harmonic frequency is not aligned
to the actual harmonic frequency. This will happen when the MIDI Note is
used for pitch control and the note is out of tune. In this case, use Pitch
Detection.
Next, go back to the Synthesis Looper tool and check Retain Noise.
Finally, specify a Sidelobe Width (%) curve that resembles the one on your
report and press the Do It button. This is a quality control step and should
result in a loop very close to your original sound.
Now the fun begins: Select Retain Noise as desired. Experiment by carefully
adjusting the Sidelobe Width (%) curve to have less width than the original
and press Do It. (Remember to Undo between trails.)
A FINAL NOTE
Remember this: Ensemble sounds vary. When you make a loop you will hear
the variations repeat, over, and over, and over, and over... You can make a
static sound that doesn’t vary (use zero Sidelobe Widths or use Freeze
Looper) but that won’t sound like an ensemble. You can’t have it both
ways.
However, this tool lets you determine the trade-off, giving you unprec-
edented control of the of the result. 
						

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Appendix A: Keyboard Shortcuts
PRESSING SHIFT+ OPTION  
WILL TEMPORARILY    
PUT INFINITY INTO    
SELECTION MODE    
PRESSING THE  
SPACE BAR    
ACTUATES THE    
SPEAKER ICON    
The keyboard command equivalents listed below
are grouped by function. For instance, commands
that scroll the data in the Mainview are grouped
together. Keys that have names, like Shift, will be
shown as . Two named keys that are used
together look like .
Pressing on the Palette and using Balloon Help
will show many keyboard shortcuts.
SCROLLING DATA
TO: KEY COMMAND:
Scroll Mainview to the right 
Scroll Mainview to the left 
Scroll Mainview up 
Scroll Mainview down 
Scroll right by one windowful 
Scroll left by one windowful 
Scroll up by one windowful 
Scroll down by one windowful 
Scroll full left and center 
Scroll Mainview to the loop start
x-[
Scroll Mainview to the loop end
x-]
Full zoom to loop start function  [
Full zoom to loop end function  ] 
						

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CHANGING DISPLAY SCALING
TO: KEY COMMAND:
Double vertical display resolutionx 
Halve vertical display resolution
x 
Double horizontal display resolution
x 
Halve the horizontal display resolution
x 
Go to minimum vertical display resolution 
Go to maximum vertical display resolution 
Go to minimum horizontal display resolution 
Go to maximum horizontal display resolution 
Fit the current selection in the Mainview
x-F
Full zoom to the loop start function  [
Full zoom to the loop end function  ]
FILE COMMANDS
TO: KEY COMMAND:
Create a new soundfilex-N
Open an existing soundfile
x-O
Close a window
x-W
Save a soundfile (update the backup file)
x-S
Get information about a soundfile
x-I
Quit Infinity
x-Q
EDIT COMMANDS
TO: KEY COMMAND:
Cut data from the soundfile into the Clipboardx-X
Copy data into the Clipboard
x-C
Paste data from the Clipboard
into the soundfile
x-V
Clear data from the soundfile (delete)
x-B or 
Clear Unselected data from the soundfile
x-T
Mix
x-M
Create or delete loop points
x-P
Select the loop data
x-L
Select all the data in the soundfile
x-A
To drag both loop points simultaneously  drag 
						

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LOOPING TOOLS
TO: KEY COMMAND:
Call the SPR Looperx-1
Call the Rotated Sums Looper
x-2
Call the Freeze Looper
x-3
Call the Crossfade Looper
x-4
PALETTE
TO: KEY COMMAND:
Momentarily put the active window
in Zoom Mode 
Momentarily put the active window
in Selection Mode 
Play/Stop the active soundfile 
Create or delete loop points
x-P
Scroll the Mainview to the loop start
x- [
Scroll the Mainview to the loop end
x- ]
Fit the current selection in the Mainview
x-F
OTHER
To cancel playback and many processing operations  or 
x-. (period) 
						

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Index
Symbols
% Retain Noise  59
A
Action Icons  11
Display Scale  11
Fit Selection  11
Loop End  11
Loop Points:  11
Loop Start  11
Speaker  11
Adjusting Blend Parameters  33
Amplitude Spectrum (dB)  62
Antares Audio Technologies  ii
Audio IFF  37
Authorization  ix
Auto-Scan Arrows  42
Auto-Scan Matching Value  43
Auto-Zero  30, 37
B
Backup Files  14
Blend Parameters  37
Blend Taper  37
Blend Time  37
Blending  36
C
Change Gain…  28
Changing Display Scaling  68
Changing The Display Resolution  17, 26
Clear  26
Clear Beyond Loop End  26
Clear Unselected  26
Clipboard  37
Copy  25, 26
Create Backup Files  36, 37
Create/Delete Loop Points  28
Crossfade  33Crossfade Length  47, 50, 54, 60
Crossfade Length (%)  43
Crossfade Looper  2, 41
Crossfade Loops  5
Crossfade Taper  44, 47, 51, 54, 60
Customizing Your Environment  36
Blending  36
Create Backup Files  36
Playback Auto-Reset  36
Scroll After Playback  37
Soundfile Window  37
Cut  24, 26
D
Disk Based Files  12, 13
Display Scale  11
Display Scale Icon  17, 26
Do It  47
E
Edit Blend Settings dialog  37
Edit Blending  31, 37
Edit Commands  68
Editing Functions  24, 26
Adjusting  Blend Parameters  33
Auto-Zero  30
Change Gain…  28
Clear  26
Clear Beyon Loop End  26
Clear Unselected  26
Copy  25
Create/Delete Loop Points  28
Cut  24
Edit Blending  31
Invert  27
Locating Loop Points  29
Loop the Selection  29
Mix  26
Normalize  28
Paste  25
Reverse  27
Set MIDI Note…  29
Show Clipboard…  30
Silence  27