# piper > A fast, local neural text to speech system. > Try out and download speech models from . > More information: . - Output a WAV [f]ile using a text-to-speech [m]odel (assuming a config file at model_path + .json): `echo {{Thing to say}} | piper -m {{path/to/model.onnx}} -f {{outputfile.wav}}` - Output a WAV [f]ile using a [m]odel and specifying its JSON [c]onfig file: `echo {{'Thing to say'}} | piper -m {{path/to/model.onnx}} -c {{path/to/model.onnx.json}} -f {{outputfile.wav}}` - Select a particular speaker in a voice with multiple speakers by specifying the speaker's ID number: `echo {{'Warum?'}} | piper -m {{de_DE-thorsten_emotional-medium.onnx}} --speaker {{1}} -f {{angry.wav}}` - Stream the output to the mpv media player: `echo {{'Hello world'}} | piper -m {{en_GB-northern_english_male-medium.onnx}} --output-raw -f - | mpv -` - Speak twice as fast, with huge gaps between sentences: `echo {{'Speaking twice the speed. With added drama!'}} | piper -m {{foo.onnx}} --length_scale {{0.5}} --sentence_silence {{2}} -f {{drama.wav}}`