I recently stumbled on this free orchestral sample library by Mattias Westlund called Sonatina Symphonic Orchestra and I have to say that some of the sounds challenge some of the commercial orchestral sample libraries! These will nicely spice up your electronic tracks. Definitely recommended.
Sonatina Symphonic Orchestra is a free orchestral sample library. While not as advanced or ambitious in scope as commercial offerings, SSO contains all the basic building blocks for creating real virtual orchestrations. It’s primarily aimed at beginners, but also more experienced composers looking for something lightweight and/or portable might find it useful.
The sounds are in .sfz format so the best way to start playing with them is to download and install the free SFZ Player by Cakewalk.
SSO works properly also with ARIA Engine, and the free SFZ Player. The library has also been tested on Shorcircuit 1, discoDSP HighLife and WusikStation 6, all of which appear to have very poor sfz support and are not recommended.
The SSO samples are stereo, 16 bit, 44kHz. Melodic instruments and chromatic percussion are sampled in minor 3rds. Staccato/pizzicato patches have 2x round-robin. All samples have varying amounts of stage ambience, depending on their front-to-back placement, but in addition to that, a good hall reverb is a must.
Licensing: SSO is a free (as in speech, and beer) library released under the Creative Commons Sampling Plus 1.0 license.