The synthesis window provides controls for running Csound in its normal mode, processing input files describing a set of instruments (an orchestra) and a sequence of events directing those instruments (a score). Optionally, the synthesis process can also be driven by a MIDI file, or by realtime events from a number of sources.

There are a lot of options for sound synthesis; most of them are accessible via a separate options window. The following controls are present in the main synthesis window:

Orchestra File

The name of the file containing definitions of the instruments used for sound synthesis. See the Csound documentation for a description of the orchestra language.
This is a mandatory entry field.

Score File

The name of the file containing a list of events and waveforms which will drive the synthesis process. The file must be in standard numeric score format; SCOT format is no longer supported.
This is a mandatory entry field.

Extract File

If given, this file name is passed to Csound to specify that only a part of the score file should be processed. The format of extract files is documented in the Csound manual.

Sound Input File

If the orchestra contains instruments which use the sound input opcodes in, ins or inq, they will read from the file specified in this entry field. Realtime sound input is possible by entering either adc or devaudio.[1]
NOTE: The Csound Shell does not permit data to be read from the standard input stream; the file name must be given if the orchestra uses the sound input opcodes.

Line-Oriented Input

The value of this field, if given, is passed to Csound as the argument of the -L command-line option. Csound will read note events in standard numeric score format from this file and process them as if they came from the score file. Realtime processing is possible by entering the name of an input device (like /dev/ports/serial1 on a BeBox).

MIDI Input

Csound can read and process MIDI events. It will read them from the file (or device) named by this entry field. The small button pops up a menu of MIDI producers which are available for use.
NOTE: When reading MIDI events, there should be an f0 statement in the score file, otherwise synthesis may end before all MIDI data have been processed. See the Csound manual for details.

Realtime MIDI Input

If this option is selected, Csound expects the MIDI data to come from a real MIDI source.[1] If this option is not selected, Csound expects input to come from a MIDI file in one of two formats: standard MIDI file format 0 (single track) or MPU401 format.
See the chapter on MIDI Support for a description of realtime MIDI processing in BeOS.

Sound Output File

Csound writes its synthesized output into the file named by this entry field. If no file name is given, Csound uses a default ("test"). A value of either devaudio or dac selects realtime output.[1]
NOTE: Output to the standard output stream is not really useful when using the Csound Shell.

MIDI Output

Although Csound's main purpose is the synthesis of sounds, newer versions can also output MIDI events (with a suitable orchestra file). The MIDI events are directed at the MIDI consumer named by this entry field.[1] The small button pops up a menu of MIDI consumers which are available for use.
See the chapter on MIDI Support for a description of realtime MIDI processing in BeOS.

Transcript

If this entry field contains a filename, all messages printed by Csound are logged and written to the named file.

Synthesize

Clicking on this button (when enabled) starts Csound in its synthesis mode.

Abort

Clicking on this button (when enabled) causes a running synthesis to be aborted.

Options

Shows resp. hides the synthesis options window.

A synthesis options window is always associated with a synthesis window, and its controls have effect on the job associated with that window. For this reason, a synthesis options window has no menu and does not provide a means to start Csound execution.

Controls in the synthesis options window are grouped according to their type.

Verbose Orchestra Translation

Causes Csound to print detailed messages about translation and performance (useful for debugging an orchestra).

Display Note Amplitude Messages

If switched on, each note being processed produces a message containing its time, duration and amplitude.

Display Out-of-Range Messages

Controls warnings about output samples which had to be clipped because they exceeded the range representable by the selected sample format.

Display Warnings

Enables various warning messages.

Show Heartbeat

Causes a "heartbeat" character to be printed each time a block of samples is written to the output file.

Notify at End of Job

Signals the end of processing via an acoustic signal.

Preprocess Score

If switched on, the score will be preprocessed by cscore. This requires a version of Csound which has the desired cscore routine compiled in. It won't work with the default executable.

Init-Time Processing Only

Causes Csound to only process init-time statements in the orchestra. No samples are produced and no output file is generated.

Inhibit Soundfile Output

Causes the synthesized sound samples to be discarded.

Rewrite Soundfile Header

When selected, the output file's header (if any) is rewritten each time a block of samples is appended to the file. This makes the file playable even if Csound is aborted before synthesis is complete.

Defer Soundfile Loading

Controls the time at which soundfiles will be loaded by GEN01 statements in the score. Normally they are loaded when the function-table is created; if this option is switched on, loading is deferred until performance time.

Terminate at End of MIDI Track

Causes synthesis to end after the last MIDI event has been processed. When synthesizing from MIDI, the score usually just contains function table data and an f0 statement long enough to allow the whole MIDI track to be processed. Unless this option is selected, the output file will be padded with zeroes until it has the length determined by the score.

Software Buffer Size

Size of the buffer used to accumulate samples during synthesis. The default value (used if the field is left empty) is 1024 sample frames. If a negative number -N is given, the buffer size will be N * ksmps, where ksmps is the number of samples per control period defined by the orchestra.
This parameter also affects realtime audio I/O; see the Csound manual for details.

Hardware Buffer Size

Number of sample frames in the realtime I/O (ADC/DAC) buffer. The default value is 1024; it can be tuned to reduce latency (using smaller values) or dropouts (using larger buffers). See the Csound manual for details.

Sample Rate Override

Overrides the orchestra's sr parameter. The sample and control rate must be either both left alone, or both overridden. The sample rate must be divisible by the control rate.

Control Rate Override

Overrides the orchestra's kr parameter. See previous item.

Tempo

Sets the initial tempo used to process the score, and allows the tempo to be controlled from the orchestra using the tempo opcode. The value is given in beats per minute.

8-Bit Signed

Signed bytes (-128 .. 127).

8-Bit Unsigned

Unsigned bytes (0 .. 255). Offset by 128 relative to the signed format.

A-Law

Samples compressed to 8 bits using the "A-Law" compression function (Reference: CCITT Recommendation G.711).

µ-Law

Samples compressed to 8 bits using the "µ-Law" ("Mu-Law", "U-Law") compression function (Reference: CCITT Recommendation G.711).

16-Bit Signed

Signed 2-byte integers (-32768 .. 32767). This is the default format.

32-Bit Signed

Signed 4-byte integers (-2147483648 .. 2147483647).

32-Bit Float

Single-precision IEEE floating-point numbers (ca. 1.2e-38 .. 3.4e+38).

Raw Data

The output file does not contain any header or format information.

IRCAM

The output file contains an IRCAM soundfile header (unless Csound has been built with a different default soundfile format).

AIFF

The output file will be in AIFF format.
NOTE: If the selected sample format is 32-Bit Float, the output will actually be an AIFC file. If the selected sample format is not legal for an AIFF file, a different sample format will be substituted.

WAV

The output file will be in WAV format.
NOTE: If the selected sample format is not legal for a WAV file, a different sample format will be substituted.

None

No diagrams will be generated. This is the fastest option.

ASCII

ASCII graphics will be sent to the standard output stream.

PostScript

Embedded PostScript diagrams will be written to a file in the same directory as the output file, with the output file's base name and the extension eps.

Graphics

Diagrams are displayed in windows.[2]

[2] Graphical displays are possible only when the Csound Server is running.