A particular type of free content, or a particular subclass of data sets, for making your own music.
Freesound the incredible collaborative sample/field recording community.
See also freesound4s the tagged and compressed 4-second subset
FSI language courses are US-government-developed English↔︎[insert politically-sensitive language here] courses in the public domain.
Free from any hint of modern pedagogical best-practice.
legowelt sample kits are a cult phenomenon from weird dutch guys who played a gig at my local cafe that one time.
Alex Mcleans Dirst Samples are fun and come with a supercollider binding
Who knows which of these are legal, but there is an endless churn of drum sample over on Reddit.
Impulse Response libraries
Libraries of reverbs, that may be convolved with a signal to make it sound like it was recorded somewhere else - e.g. record a sound in a church then play back other sounds as if they were played in the church. Aside: there is an interesting deconvolution problem in making these things, and possibly an even more interesting one in synthesising them.
Sources, via, e.g. sidebrain:
- Teufelsberg radome impus responses by Balance mastering.
- The Echo Thief – A professor at UCSD who travels the world and record real places
- EMES Virtual Rooms – Offer Free IRs on the bottom left of the screen
- Adventure Kid – Spring IRs
- Rekkerd Impulse Response Blog – Articles and posts about convolution sound design
- Fokke Van Saane – A lot of really unique IRs. Make sure you download the Wav version of the packs.
- Lexicon 480L – Beautifully sounds IRs from the famous Reverb Unit.
- SIR ships with some examples
- Boss GT-8 – IR from the Hardware unit
- CKSDE – Separated IR Downloads
- dubbhism Stonerverbs
- Diego Stocco’s majestic mutant wierdverbs
- OpenAIR (UK-based sampled IRs)
- freeverb lists some more
- Noisevault Studio and Convolution Forums
- Voxengo Pristine Space
- Voxengo Free reverb
- echochamber’s impulse responses
- Interruptor’s music - Club Simulation
- Prosoniq Impulse Reponse Download
- K7 Sounds
- signaltonoize.com Impulse Sets
- Auditorium Measurement
- Open Impulse Response Library
- freesound IR
And ultimately anything can be treated as an impulse response; although you might have to do some fancy footwork to make it sound ok - see above re: deconvolution.