SID Factory II is a cross-platform editor for composing music that will work on a Commodore 64. It uses the reSID emulator and is currently in open BETA. You can download binary release builds from here. To build from source, have a look here.

Main programming by Thomas Egeskov Petersen, with assistance by Jens-Christian Huus and Michel de Bree.

Notable features:

• Uses the renowned reSID emulator
• Tracker-like interface, using JCH's contiguous sequence stacking system and Protracker note input layout.
• Choice of various music drivers made by pioneer musicians Laxity and JCH , optimized for use in demos and games on the Commodore 64.
• A hotkey opens a surrounding overlay with help for both editor and driver.
• Imports Goattracker, CheeseCutter and MOD files.
• Supports both SID models 6581 and 8580 for PAL and NTSC.
• Unlimited undo
• Multiple songs
• Copy / paste and modify selected area
• Built-in packer and relocator to position the music anywhere in the Commodore 64 memory. Relocate used zero page addresses.
• Includes demo tunes to learn from.
• Cross platform: Windows, macOS (Intel and ARM) and Linux versions.
• Configurable settings, shortcuts and keyboard layout
• Open source

Please report issues in our issue tracker.

• Added: #102 Visualizers for pulse width (per channel), filter cutoff and an indication per channel if it is being filtered.
• Added: Config option Visualizer.PulseWidth.Style to set the default style for the pulse width visualizer.
• Changed: New default driver is 11.05.00
• Added: #156 Configuration option Disk.Hide.Extensions to hide files with certain extensions in the file browser. Default values are .sid, .wav and .mp3
• Changed: Configuration parameter Window.Scale now has a range from 1.0 to 10.0, so users can blow up the screen even bigger. Values below 1.0 were not working correctly.

• Fixed: #162 Crash when converting NP20 and GT tunes.
• Fixed: Crash when using a loop point beyond position 128
• Fixed: #161 A bug where sometimes you couldn't edit sequences before hitting the play button.

• Added: #37 Multi song support. Allows you to edit multiple order lists that share the same sequences and sounds. Press F7 to check it out.
• Added: Marking and copy/paste functionality in the song list
• Added: Marking and copy/paste inside sequences (even across boundaries)
• Added: #74 Configurable virtual piano keyboard layout. (Thanks to Wolfgang Kreutz for requesting)
• Added: #119 A song can be made to stop playing instead of looping.
• Added: An option to set the emulation sample rate to a user defined value (Thanks to Tammo Hinrichs for implementing)
• Added: More than 30+ new source tunes by JCH and Vincenzo
• Fixed: Scrolling in the song list using the mouse wheel
• Fixed: reSID won't output a click anymore when launching SID Factory II or loading/saving files (Thanks to Tammo Hinrichs for implementing)

• Added: You can now add labels for song list rows. Left-click to edit a label.
• Added: Note delay; delay a note by 0-F ticks. This is a feature of the new default driver 11.04
• Added: An option in the packer to specify the base for zero page addresses that the player uses.
• Added: Documentation on how to customize configuration using a user.ini file. Including a default template in /documentation/user.default.ini.
• Added: Configuration options:
  • Window.Scaling to scale the contents of the window. (Thanks to Matty Seito for suggesting)
  • Editor.Driver.Default to set the default driver that is loaded when starting up the editor.
  • Editor.Confirm.QuickSave to enable/disable confirmation dialog on quick save.
  • Sound.Output.Gain for boosting/lowering output volume of the editor.
  • Disk.UserFolders and Disk.UserFolders.Aliases to add your favorite folder shortcuts to the file browser.
  • Disk.Startup.Folder to set the default startup folder for the file browser.
  • Editor.Follow.Play to set default follow play on/off.
  • Editor.Sequence.Highlights to set default sequence highlights on/off.
  • Sound.Emulation.8580.FilterCurve for adjusting the filter of the 8580 model.
  • Sound.Emulation.6581.FilterCurve for adjusting the filter of the 6581 model.
  • Sound.Emulation.Default.Model to set the default SID model (6581/8580) on startup.
  • Sound.Emulation.Default.Region to set default region (PAL/NTSC) on startup.
• Changed: #142 the list of keycodes that can be used for remapping is complete now. Please note: the names for keycodes starting with num are renamed to start with kp_.
• Changed: macOs #146 the official macOS distribution is now a universal application, meaning it will run native both on the new M1 (arm64) and the Intel (x86_64) architecture. The architecture the application is running on is reflected in the build number in the lower right corner of the startup screen.
• Fixed: More accurate clockspeed (Thanks to Lazlo Vincenzo Vincze for reporting)
• Fixed: macOs #131 SF2 won't compile on mac with Silicon M1 CPU. (Thanks to Rolf Greven for reporting and suggesting the fix)
• Fixed: linux #133 Emulation error when starting up linux version. (Thanks to Maurizio Dall'Acqua for reporting)
• Fixed: linux #134 SF2 won't compile on Arch Linux (Thanks to jansalleine for reporting and suggesting the fix)
• Fixed: #137 Instability in filter table when jumping to set command in default driver.

• Added: The converter has now been embedded into the editor; just load MOD, SNG or CT directly
• Added: Converting from MOD will show a dialog for choosing which of the four channels to ignore
• Added: Ctrl-Shift-F for inserting the first empty unused sequence
• Added: Ctrl-D for duplicating and replacing the currently edited sequence
• Added: Ctrl-Shift-D for duplicating and appending sequence after the currently edited sequence
• Changed: Splitting a sequence with Ctrl-B now splits to the first empty unused sequence
• Changed: macOS Copy/Paste/Undo/Redo are now under the standard macOS key combinations (Cmd-C, Cmd-V, Cmd-Z, Shift-Cmd-Z) (Thanks to Bastiaan Winde for reporting)
• Fixed: #91 cannot edit tracks anymore after dialog has been shown. (Thanks to Arjen Bokhoven for reporting)
• Fixed: macOS #71 switch instrument/command while in a table (Thanks to Adam Davidovics for reporting)
• Fixed: macOS #67 crash when run from a path with spaces (Thanks to Arjen Bokhoven for reporting)

• Driver update 11.03 adds a filter enable flag bit in the instruments

• The standalone converter has been removed due to the converter nowing being embedded into the editor

• The overlay can now be shown inside the editor with F12 and also changes depending on what driver is loaded
• Added Ctrl+L for setting a song loop position (the order list words will turn green in that spot)
• It is now possible to delete a file in all file dialogues by hitting the appropriate key
• Seven new color schemes have been created in addition to the default one
• The importer now also carries over auxiliary data (e.g. table descriptions)
• Upgraded the ReSID emulation (resid-fp) to the latest version
• Fixed .. erroneously interpreted as a file to be opened instead of browsing back
• Fixed tracks not unmuted properly after muting them and then loading a different .sf2 file
• Fixed the editor crashing when trying to optimize a song with no sequence data
• Fixed not being able to properly play from a bookmark when showing tracks of uneven lengths
• macOS Now using Minus and Shift+Minus for fast/faster forward
• macOS Instrument up/down is now Cmd+Up/Down while Command up/down is now Shift+Cmd+Up/Down
• macOS You can now open .sf2 files with SID Factory II directly from Finder (Open With)
• macOS Backward compatible until macOS 10.9 (Mavericks)

• Driver update 11.02 adds commands for pulse program index, tempo change, and main volume

• Added a third conversion option for handling .ct source tunes from CheeseCutter
• The SNG and CT converters now support the pulse index and main volume commands in driver 11.02
• The MOD, SNG and CT converters now support then tempo change command added in driver 11.02
• Command description labels are now created by the MOD and SNG converters too

• Expanded the user manual with a table of contents, chapters about the data tables, and various pictures
• The notes.txt file has been overhauled to show a complete list of all default keys for both Windows and macOS
• The text files for all of the drivers have been polished to be easier to read at a glance

• The PowerShell script for the bright overlay is now deprecated and will no longer be included
• The area previously known as the gray order list is now called the song list instead

• Added a dialog box message for when saving fails
• Added a dialog box message for when selecting a folder fails
• macOS Fixed crash bug when trying to open a folder you had declined from a system dialog
• macOS Editor ran without SDL2 being installed; added latest version of SDL2 to the package
• Fixed crashing when trying to display unknown characters (usually in the file menu)
• Fixed note preview using Caps Lock not working
• Fixed note preview sometimes behaving inconsistently
• Fixed left/right "blindness" in user manual

• Added description labels in the command and instrument tables
• All drivers have been updated with meta data for the new descriptions capability
• Also updated all the demo songs with command and instrument descriptions
• Updated the converter to copy instrument descriptions from GT2 and MOD files
• Changed hotkey for bit editing in tables to Shift+Enter because of descriptions now using the Enter key
• Improved the table layout handling to allow for vertically tiled tables
• All tables can now be accessed with an Alt+[letter] hotkey (the letter is highlighted in the table name)
• A separate macOS build has been released for the first time (maintained by Michel de Bree)
• Added the Ctrl+U hotkey for toggling between lower and upper case letters for all hexadecimal values
• You can now drag-and-drop an .sf2 source file directly into the editor
• Added an exit application confirmation dialog
• All file lists now include a .. line for browsing back to the parent folder
• Upgraded the ReSID emulation (resid-fp)
• Changed the application caption text (filename now comes first)
• Debug functionality added for examining ReSID output
• Fixed a threading issue that could cause instability in the ReSID emulation
• Fixed inserting/deleting rows in sequences not immediately being reflected in the order list overview

• Updated fast forward: ½ = 4x update, Shift+½ = super fast update
• Added Ctrl+I during sequence editing for inserting the current selected instrument value. If a value is already set, it will be cleared
• Added Ctrl+O during sequence editing for inserting the current selected command value. If a value is already set, it will be cleared
• Added Ctrl+Space during table editing (if keyplay mode is on) - will play like Space alone but apply the current highlighted command, regardless of which table is in focus
• In the marker view, Enter (or left-click) will move the current track position to that of the marker. Ctrl+Enter (or double-click) will do the same and then start playback
• Reversed the direction of the CPU usage graph
• Added command-line parsing, so that it is possible to associate .sf2 files with the editor and open them in File Explorer
• Added NumPad+Plus and NumPad+Minus for incrementing and decrementing the currently selected index of the instrument table
• Added Ctrl+NumPad+Plus and Ctrl+NumPad+Minus for incrementing and decrementing the currently selected index of the command table

• Fixed the meta data for command action keys (jump to relevant tables on Ctrl+Enter) in all variants of driver 11

• Fixed import strings to say import music data and dialog box to reflect the same too
• Fixed importer assertion when trying to import an empty project (i.e. a driver)
• Fixed Ctrl+V (paste) not notifying the order list overview
• Editing octave down/up has been moved to F3 and F4, transpose current sequence one semi-tone down/up has been moved to Shift+F3 and Shift+F4, and transpose current sequence one octave down/up has been moved to Ctrl+F3 and Ctrl+F4
• Added fast forward on the ½ key
• Fixed a bug in directory enumeration that would cause a crash when trying to access some system files

• Added automatic update of build data which is printed in right bottom of the splash screen
• Added PNG support and a temporary embedded logo
• Pressing End in a table will set the row of the last occurrence of a zero-only row found from the bottom and upwards
• OrderlistOverview: Added Ctrl+Enter to move to and start playing from position
• OrderlistOverview: Mouse left-click will select and move tracks view to position
• OrderlistOverview: Mouse double-click will select and move tracks view to position and start playing from position
• OrderlistOverview: Implemented Page Up and Page Down (skips 20 lines)
• OrderlistOverview: Added Home which goes to top visible then first index, and End which goes to last visible then last index
• Tracks and order list focus: Fixed issue where cursor position would be misaligned when focusing on order list entry and pressing Ctrl+G
• Changed Shift+F2 to play from the event position of the top current sequence of the track in focus (or last in focus)
• Added Space during table edit for previewing the last note played with Shift+[note] value (this will do nothing if not already in "play through input" mode)

Changes to earlier versions are not available.