Audio Fading

Discussion in 'The Projects Forum' started by suvenier, May 13, 2009.

  1. suvenier

    Thread Starter New Member

    Jul 30, 2008
    3
    0
    Hello to you.

    I'm building a simple electronic sound syntetizer.

    Basicly It consists of several coupled oscilators, each conected to a key on a key board, that connects the sound to a signal mixer (and amplifier) and finaly to the sound output.

    What I would want to accomplish is a fader effect on the key strokes, I mean, when you play a piano key and they take off your finger, the tone will keep going for a few seconds, fading away.

    OK so I know how to keep the tone active after you take of your finger (just add a simple Rc timer to keep the signal flowing) , but I dont know how to add the fade out effect.

    can you help?

    thank you.
     
  2. bertus

    Administrator

    Apr 5, 2008
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  3. KL7AJ

    AAC Fanatic!

    Nov 4, 2008
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    Howdy:

    It sounds like what you need is a one shot (monostable multivibrator) followed by an RC time constant. A one-shot is very easy to create with a 555 timer....probably redundant to descibe the circuit, as it's been beaten to death on this forum. :)

    Have you had success in using an RC time constant to create your decay envelope? If so, the addition of the one-shot should be a snap.

    Eric
     
  4. suvenier

    Thread Starter New Member

    Jul 30, 2008
    3
    0
    Thank you a lot. I spent a lot of time searching for material and studiyng what you gave me.

    But I realised I dont really need a complete ADSR.

    Is'nt there a much simple way to perform the envelope effect? I dont need the four effect stages (Attack, Decay, Sustain, and release), I just need sustain and realease.
     
  5. bertus

    Administrator

    Apr 5, 2008
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