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My first LV2 plugin

My first LV2 plugin

Recently I wrote my first LV2 plugin. It’s an additive singing synthesizer similar to Madde by Svante Granqvist but it also uses the Excitation plus Resonance voice model that is used by VOCALOID. It runs in realtime and it can be controlled using a MIDI keyboard. But it can also act as a placeholder for the singing voice in an Ardour project when composing songs.

LV2 is a plugin standard for free software developers that allows decentralized extensibility. It is a replacment for the older LADSPA and DSSI plugin standards that are commonly used with older DAWs such as Rosegarden and LMMS. Unlike other well known plugin standards such as VST there are no licencing restrictions in LV2. There is a small program called Jalv which connects your LV2 plugins to Jack and makes testing easy. It is also possible to combine multiple plugins and applications using Patchage which allows you to make modular synthesizers.

The MaddeLOID plugin is part of my work on free virtual singer project which aims at building a free software replacement for both VOCALOID and UTAU. There are already some free programs such as jcadencii, vConnect-STAND and Sinsy, but most of them lack flexibility and support for other languages than Japanese. Therefore I started writing my own programs that fill the gap and improving existing ones where it should be done. New features such as Non-Session Management and Jack Transport are likely to be added to the QTau Editor, which currently lacks both a working synthesizer and a lyricizer. I dedided to use eSpeak as the speech synthesis backend, which does two different things. First words are converted to phonetic symbols, and in the second step the waveform is generated. Then WORLD is used to change the length of the notes and to apply vibrato and portamento. All of my programs and related documentation can be cloned from my gitorious.

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