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- Audio Compositor 4.1 Release Notes
-
- Welcome to Audio Compositor 4.1! If you upgraded from version 4.0,
- this release brings you some minor sonic improvements:
-
- - Output from the realtime synth is a bit cleaner.
-
- - The renderer adds dither noise when creating 16-bit output .wav
- files. If you don't know what this means, don't worry about it!
-
- If you're upgrading from an even earlier version, you'll find a lot
- that's new here. The instrument editor has been redesigned to make
- more flexible use of screen space, and to speed large copy/paste
- operations. The MIDI renderer is faster, and instrument amplitudes
- are now dead accurate. There's also DLS level 2 support, and other
- new features: for more detail read on.
-
- Revised instrument editor
-
- The instrument editor has changed significantly. The left-hand tree
- view, and the property sheets for articulation parameters are still
- there, but the upper-right quadrant of the screen is now occupied by
- up to three different windows, which may be turned on or off in any
- combination. The idea was to take advantage of large display devices
- (i.e. resolutions over 800 x 600) while keeping the program usable on
- smaller screens. The three views are:
-
- - The region grid, used to map samples to the keyboard; this is not
- greatly changed from previous versions. A new button in the
- lower-right hand corner switches the grid to "edge-locked" mode,
- meaning that when you move the border of a region its neighbor
- automatically moves along with it.
-
- - The list view, which displays the children of the object currently
- selected in the tree view. This is meant to mimic the Windows
- Explorer, and to simplify drag-and-drop operations. In particular,
- it's now possible to select more than one item in the list view (by
- clicking with the SHIFT or CTRL keys) and drag them into the tree
- view or into another editor window. In previous versions of Audio
- Compositor, you could only drag one item at a time.
-
- - The wave view, which graphs the current sample (when the
- selected object is a sample). If you don't have a large monitor
- you'll normally want to turn this window off.
-
- The three views are enabled or disabled using the buttons to the right
- of the articulation tabs; the magnifying-glass buttons give you some
- control over their relative sizes.
-
-
- "Adjust SoundFont attenuation" for correct instrument balance
-
- A new checkbox in the preferences tells Audio Compositor to interpret
- the SoundFont initial attenuation generator the way most sound cards
- do. Previous versions of AC interpreted the value literally, which could
- incorrect relative levels between instruments when rendering with
- SoundFonts. We recommend checking this box unless you specifically
- require Audio Compositor's old behavior.
-
-
- External wave editors
-
- Audio Compositor has a rather feeble built-in wave editor, which we've
- retained through the years mainly because of the ease of integrating it
- with the rest of the program. It also has one feature rarely seen in
- wave editors: it understands fractional loop points. As far as we know,
- if you want to create loops with sub-sample precision (and Audio
- Compositor's playback engine does know how to render such loops),
- you'll need the Audio Compositor wave editor.
-
- Nevertheless, most Audio Compositor users will have a dedicated
- audio editor on hand, and will prefer to use it for most sample-editing
- chores. Audio Compositor can now use an external or "alternate"
- editor if you specify its location in the Preferences window. Doing so
- activates an extra menu item in the instrument editor: for example, if
- you right-click on a sample, just below the old "Wave editor" option
- you'll find a second option called "Wave editor (coolpro.exe)" or
- something similar. Editing a sample causes its wave to be extracted to
- a temporary file called "AC Temp 000000.wav" (the numeric part will
- increment as you edit subsequent files). When you save an
- instrument bank, the instrument editor retrieves the contents of any
- outstanding temp files and commits them to the instrument bank. If
- you modify a sample in a wave editor, and want the modified sample
- saved to a DLS or SoundFont file, you must save your work from the
- wave editor first, and then save the instrument bank.
-
-
- DLS Level 2 support
-
- Audio Compositor will now read and perform DLS Level 1 or Level 2
- files, and can write DLS files that can be read by both Level 1 and
- Level 2 devices. Because the Level 2 specification is more
- comprehensive, less information is now lost when an instrument file is
- saved in DLS level 2 format.
-
- Several changes to the instrument editor are designed to make Audio
- Compositor a friendlier environment for DLS and SoundFont files.
- Envelope generators are a good example. Traditionally in Audio
- Compositor, envelopes can have any number of segments and can be
- drawn with the mouse in virtually any shape. While this flexibility has
- some advantages, it's at odds with the rigidly-defined six-stage
- envelopes which are becoming standard in other applications. Audio
- Compositor envelopes now come in two varieties. A "six-stage"
- envelope has the standard segments (delay, attack, hold, decay,
- sustain, release) and can be written to a DLS or SoundFont file without
- modification. The older type of free-form envelope is now referred to
- as a "custom" envelope. Avoid custom envelopes unless you will be
- saving your work to Audio Compositor's native .ACP file format; they'll
- be simplified as necessary if you write them to a DLS or SF2 file.
-
- Modulation routings are a similar story. In earlier versions of Audio
- Compositor, you could use the mouse to draw an arbitrary relationship
- between a modulation source (e.g. the mod wheel) and a destination
- (e.g. an LFO depth). That relationship is referred to as a "transform"
- in today's jargon. The traditional freehand routing is still available in
- Audio Compositor, but you must ask for it by selecting a "custom
- transform". By default, Audio Compositor will create modulation
- routings with a standard linear transform, in which the modulation
- source is applied to the destination using a simple straight-line
- relationship. (An exception to this rule is that MIDI velocity, volume,
- and similar sources are routed to output volume using the inverse
- concave transform found in most synthesizers.) These pre-defined
- transforms are the natural mode of expression in DLS and SoundFont
- files. "Custom" transforms, like custom envelopes, must undergo a
- somewhat unpredictable simplification process if they are saved to
- something other than a native .ACP file.
-
- In addition to the linear and inverse-concave transforms just
- mentioned, a variety of standardized transforms are also available.
- You can select these on the instrument editor's "Key Routings" and
- "CC Routings" tabs, but most of these can only be saved to Audio
- Compositor's .ACP file format. Modulation routings cannot be saved to
- SoundFont files because Audio Compositor does not currently support
- the SoundFont 2.1 specification. The range of modulation routings
- that can be saved to a DLS Level 2 file is limited by the DLS
- specification to the following:
-
- Key routings:
-
- - Velocity to envelope attack time (linear transform)
- - Key number to envelope decay time (linear transform)
- - Key number to envelope hold time (linear transform)
- - Velocity to filter cutoff (linear transform)
- - Key number to filter cutoff (linear transform)
- - Velocity to volume (inverse concave transform)
-
- Continuous routings:
-
- - Controller 1 to LFO1 amplitude, pitch, or filter cutoff (linear
- transform)
- - Aftertouch to LFO1 amplitude, pitch, or filter cutoff (linear
- transform)
- - Controller 1 to LFO2 pitch (linear transform)
- - Aftertouch to LFO2 pitch (linear transform)
- - Controller 7 to amplitude (inverse concave transform)
- - Controller 11 to amplitude (inverse concave transform)
-
-
- Reverb and Chorus
-
- Audio Compositor 4.0 supports reverb and chorus effects. The chorus
- effect is fairly conventional: delay and detune values can be specified
- in the Preferences. The polyphony requirement is doubled for
- instruments using this effect.
-
- The reverb effect is intended for casual use. Users who know chalk
- from cheese will continue to do what they're doing now: for example,
- adding reverb in post-processing with a proper audio editor.
-
-
- Limited-polyphony rendering
-
- The MIDI file renderer can now be told to limit its polyphony (the
- setting is at the upper right edge of the renderer window). This
- apparently backward feature is useful when you have a combination of
- an instrument with unusually long release times, and a MIDI file that
- triggers a large number of notes in this instrument, on the assumption
- that the resultant buildup of voices will be limited by hardware.
-
- Frankly, it's also a marketing ploy. In unlimited-polyphony mode, AC
- performs much more slowly than software synths that do traditional
- voice stealing. Displaying the polyphony setting at the top of the
- window makes it a bit clearer what is going on.
-
-
- Miscellaneous
-
- Every release of Audio Compositor includes countless small
- refinements suggested by users. We receive hundreds of these each
- year, and if you've written to us recently, the odds are about 50/50
- that your suggestion made it into Audio Compositor 4.0. If you don't
- see it in this version, feel free to nag us again. See you next time!
-
-