Hi Darwin, Check out the diagram here: http://www.donreiman.com/Flanger/Flanger.htm A flanger works like this: y[n] = x[n] + wetness*x[n-delay] + feedback*y[n-1]
where delay = 0.5*sample_rate / ( center_frequency + mod_depth* LFO[phasor] )
(This will be a float so you need to make an interpolated delay line for
sub-sample delays)
your LFO is a lookup table, so you will need a phasor (sawtooth oscillator
between scaled between 0 and 1) to read it.
It is also common to use a triangle wave LFO rather than a sine wave.
-David
On Jun 25, 2014, at 2:48 AM, Darwin Sese <darwins...@gmail.com> wrote:
> I am writing a basic flanger. i successfully create an delay or echo
> effects.
>
> i am coding an LFO. but i dont know how to do it. here is my code.
>
>
> LFO = (float) sin( ((double)i++/(double)TABLE_SIZE) * M_PI * 2. );
>
>
> here is my full code functions.
>
> float flanger( float input )
> {
> what is the correct value for LFO?
> LFO = (float) sin( ((double)i++/(double)TABLE_SIZE) * M_PI * 2.
> );
>
>
> //how i can put the lfo here?
> echo_buffer[echooffset]=input*0.5;
> if (echooffset++>=ECHO-1)echooffset=0;
> output+=echo_buffer[echooffset]*0.4;// amount to mix into dry
> if (echooffsetplay++>=ECHO-1)echooffsetplay=0;
>
>
>
>
>
>
> return output;
>
>
>
> }
>
>
>
> Thanks in advance.
> Darwin
>
>
>
>
>
> --
> Darwin Sese
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