Credits and licenses.
Koprod
Koprod is built on these open-source projects and free sound libraries.
Grand Piano: Salamander Grand Piano V3
By Alexander Holm, a Yamaha C5 recorded with two AKG C414 microphones; retuned version by Markus Fiedler. Licensed under Creative Commons Attribution 3.0. Koprod ships five of its sixteen velocity layers, resampled, shortened with fades, levelled and re-encoded.
If you release music that uses the Grand Piano, crediting “Salamander Grand Piano by Alexander Holm” follows that license.
Orchestral instruments: VS Chamber Orchestra: Community Edition
By Versilian Studios (Sam Gossner) and Ivy Audio (Simon Dalzell), with sample cutting by Elan Hickler / Soundemote. Released under CC0 1.0. Homepage: VSCO: Community Edition. The authors ask that the samples not be sold on their own; Koprod ships them only inside the app.
Wurlitzer and Electric Grand: Greg Sullivan’s E-Pianos
A Wurlitzer EP200 and a Yamaha CP80 sampled by Greg Sullivan, mapped to SFZ by kinwie (sfzinstruments). Licensed under Creative Commons Attribution 3.0. Koprod ships three of their four velocity layers, resampled, shortened with fades, levelled and re-encoded.
If you release music that uses the Wurlitzer or the Electric Grand, crediting “E-Pianos by Greg Sullivan” follows that license.
Rock Drum Kit: MuldjordKit
Recorded by Lars Muldjord for DrumGizmo; stereo version by the FreePats project. Licensed under Creative Commons Attribution 4.0.
If you release music that uses the Rock Drum Kit, crediting “MuldjordKit by Lars Muldjord (DrumGizmo)” follows that license.
Guitars, keys and world instruments: FreePats
From the FreePats project, released under CC0 1.0: FSBS Electric Guitar Clean #1, Clean #2 (Jazz) and Distorted #1; Spanish Classical Guitar; Ukulele by Mateusz Dąbrowski; Upright Piano KW; Button Accordion HN (recorded by Jeff Stauffer, prepared by michael02022); Kalimba, Hang in D minor and World Percussion, recorded with Xavimart; Old Piano FB by Piotr Barcz; Bagpipe by Gilles Sadowski.
Bass, saxes, cello, voice, piano and brushes: Karoryfer Lecolds
Growlybass (a Squier Jazz Bass), Swirly Drums (a jazz kit played with brushes), Weresax (alto sax), Bear Sax (baritone sax), Karoryfer x bigcat cello (played by Kamila Borowiak), Osiris Piano and the Hadzi-Fia “a” vowel, by Karoryfer Lecolds, released under CC0 1.0.
Upright Bass and Erhu
D. Smolken’s double bass (a 1958 Otto Rubner) and the Aliexpress Erhu, from sfzinstruments, released under CC0 1.0.
Studio Drum Kit, tenor sax, keys, world instruments and Latin percussion: Versilian Studios
Virtuosity Drums and the Versilian Community Sample Library by Versilian Studios, released under CC0 1.0.
Steel Drums: jSteelDrum
A hand-made Trinidad steel pan sampled by Jeff Learman (sfzinstruments), dedicated to the public domain under the Unlicense.
Split & rebuild: Spleeter and Basic Pitch
Stem separation uses Spleeter 4-stem by Deezer Research, licensed under the MIT License, converted to ONNX. Note transcription uses Basic Pitch by Spotify, licensed under the Apache License 2.0. Both run on your Mac in ONNX Runtime (MIT License); their license texts ship with the app.
Interface font: Instrument Sans
By Rodrigo Fuenzalida and Jordan Egstad, licensed under the SIL Open Font License 1.1. The app bundles it so it works offline; this site loads it from Google Fonts.
Music on this site
Every track on the showcase was made in Koprod with these instruments and Koprod’s own synths, with no outside samples or loops.
Research
Koprod’s design studied BandLab’s studio and AI features with REA. Comparison pages use public information from each vendor, cited on each page.