Hi Thanks for the help with the filter envelope I was trying to make, I have decided to use the method Pierre suggested as it allows me to alter the envelope by dragging my mouse, and it makes more sense than the v-line method at this moment in time, although I will also give that a try. I am also going to look into wavetable oscillators as a way of making band-limited waveforms (using fourier synthesis, then writing this into a table) I'll include my file to show have I have modified Pierre's additions I will return with a completed patch! thanks Samuel