Song Properties

Song Properties

This contains the settings for the following areas:

• Type
• Tempo
• Playback
• OpenMPT Version Info

Type

Here you may use the module type drop-down menu to select a different type of module. Options available are:

• Protracker MOD
• Screamtracker S3M
• FastTracker XM
• Impulse Tracker IT
• Impulse Tracker Project ITP

The letters after the module name designate the file extension that files of this type will be saved with. Each module type in the list has more features supported or channels or plugins support than the one before, be aware that changing the module type from one with more features to one with less will result in loss of information - for example MOD format has a maximum of 4 channels. It is recommended for most types of music that Impulse Tracker (.IT) files or Impulse Tracker Project (.ITP) files be used, as they are the most powerful and can handle all the modern features such as VST and VSTi automation.

Channels

The 'Channels' drop-down menu allows the user to change the number of channels available in the current song. The number of channels can be set from a minimum of 4 to a maximum of 128 again be aware that this is dependant on the type of module in use and some module types cannot have as many channels.

Embed instrument parameters in ITP

This check box toggles whether instrument parameters are stored in an ITP file or not. *neesd better explanation* This is greyed out when any other type of module is selected and is OFF by default.

Tempo

The settings here change the way tempo related commands are interpreted in the current song. These settings may be greyed out when a song type is selected which is not compatible with these tempo types.

Tempo Mode

This drop-down menu allows you to select from the following modes. Here's a brief overview of the modes, but to fully understand the interpretations of Tempo (Txx), Ticks per row (Axx with IT) and rows per beat, see this page dedicated to Tempo Modes. Here's a brief description of each mode:

• Modern - this will give an exact bpm and accurate timing
• Classic - this is the default mode. The 'bpm' given is not used accurately, but playback speed will be faithful to the original IT2/ST3/XM style and more reproducible other players.
• Alternative - you most likely don't need this one, but see the Tempo Modes page for more info.

Newer users who don't intend to play back files in other programs should stick to the 'Modern' setting. This provides the most accurate timing and is useful when exporting audio to other programs using the save as .wav function?.

Rows/beat

This allows the selection of the number of rows played per beat from x to x cHECK THIS!. This number must be smaller than that entered for rows/measure.

Rows/measure

this allows the selection of the number of rows played per measure from x to x cHECK THIS! . This number must be bigger than that entered for rows/beat.

Playback

This area contains options for changing some behaviours of the song. The options are greyed out when the current filetype is not comaptible with the settings. For reference the following table shows which features are compatible with which song file types.

	MOD	S3M	XM	IT	ITP
Linear Frequency slides	-	-	X	X	X
Fast Volume Slides	-	X	-	-	-
IT old effects	-	-	-	X	X
IT compatible Gxx	-	-	-	X	X
Extended filter range	-	-	X	X	X
Embed instrument parameters	-	-	-	-	X

Linear Frequency Slides

This checkbox enables and disables linear frequency slides. This changes the algorithm used to repitch samples by changing the playback rate. This is an option to retain backwards compatibility with old song files (especially amiga files). It is recommended that this is switched on unless old style slides are specifically required. Linear frequency slides are ON by default. (in those filetypes which support it.)

Fast Volume Slides

TODO

Old Effects

(NOTE - this is taken directly from the ittech.txt file that comes with impulse tracker)
On = Old Effects, Off = IT Effects
Differences:

• Vibrato is updated EVERY frame in IT mode, whereas it is updated every non-row frame in other formats. Also, it is two times deeper with Old Effects ON
• Command Oxx will set the sample offset to the END of a sample instead of ignoring the command under old effects mode.

IT compatible Gxx

TODO

Extended filter range

This checkbox enables and disables the extended filter range. The filter in question is the cutoff filter used on sample based instruments. The filter range is normally 130Hz - 5123Hz, when the extended filter range is switched on the range is changed to 130Hz - 10670Hz but with a slight loss of accuracy (the same number of steps are used to represent both). This is OFF by default.

Embed instrument parameters

TODO

Mix Levels

This pull-down menu gives you a selection of different mixing algorithms. They are included to maintain compatability with older versions of modplugtracker. OpenMPT 1.17RC3 is the recommended setting as it is the most up-to-date and overcomes some of the faults of earlier versions. Some details:

• Original:
• With this mode, behaviour is as close as possible to the original closed source Modplug Tracker.
• This includes a float<->int conversion bug by which audio stream levels are decreased by 2x before being sent to plugins, then amplified back up by 2x after the plugin's processing. You can verify this by rendering to WAV with MPT then recording to WAV with a plugin such as TapeIT. The WAV recorded with TapeIt will be 2x lower.
• This has the side effect of making VSTis very loud (since with VSTis you only get to hear the final 2x amplification part of the bug).
• "Global Volume" is applied to audio streams before they are processed by plugins. Therefore global volume only affects samples and does not affect the output of plugins.
• 1.17RC1:
• In 1.17RC1 a typo worsened the plugin levels bug. Levels were decreased 16x before being processed by plugins, then amplified 16x! This mode emulates this behaviour. Again, you can verify this with a plugin like TapeIt.
• VSTis are attenuated 2x to bring them in line with the rest of the audio.
• "Global Volume" is still applied to audio streams before they are processed by plugins. Therefore global volume only affects samples and does not affect the output of plugins.
• 1.17RC2:
• This mode (hopefully) fixes the plugin levels bug. Assuming global volume is at max, you should get the same levels whether you render with OpenMPT or a plugin like TapeIt. This implies that plugins are receiving the correct levels.
• VSTis are attenuated 2x to be in line with MPT's sample attenuation. However, VSTi and Sample levels can be modified at will from the general tab.
• "Global Volume" is now applied after plugins - so it now affects the final audio level, i.e. it behaves like global volume should do.
• 1.17RC3:
• Similar to 1.17RC2, except:
• The global Pre-Amp and 'Headphones' aka 'Soft Panning' settings that are available in the Sound Card settings window are ignored.
• Default sample and VSTi levels are slightly louder.
• Modifying the levels on the general tab will show the approximate resulting volume change in dB.