The best free alternative to Guitar Rig is Guitarix, which is both free and Open Source.
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- Guitarix. Free • Open Source. ...
- Rakarrack. Free • Open Source. ...
- Deplike Guitar Amp & Effects. ...
- Tonebridge. ...
- go-dsp-guitar. ...
- iShred LIVE. ...
- GNUitar. ...
- CP Guitar Effect Processor.