posted 11 February 2010 03:51            

freqmodforumquestion.kym

Mystefied in Melbourne here puzzling over implementing LFOs.

I've pasted an oscilator into the modulator field of another oscilator (see attached)

What I'm mystefied about is that if I increase the frequency of the LFO it also seems to increase the depth of the modulation as well.

See attached and presets.
Why is this so?

Can anyone point me to some good examples of LFO implementation please?
(either on the tweaky, forum or sound library)

thanks

posted 11 February 2010 12:56            

the modulation field in the osc module is like FM used in the DX7 or the Synclavier. It's called FM but it is really Phase Modulation. If you put DC in this field you will end up with the same frequency as putting zero in there but it will just be in a different phase.

The easiest way to do it is paste the LFO module into the frequency field of the Oscillator (multiply it up to the desired depth as -1 to +1 won't give much modulation) and then add the base frequency as hertz.

( ( [LFO]L *1000)+ !Freq)) hz

or to give a more consistant modulation at different base frequencies

( ( [LFO]L * 12) + !NoteNum) nn

This one gives a max modulation of +/- one octave

This will not control the pitch at sample rate but at 1 khz intervals but for LFO it won't matter.

hope it helps

posted 11 February 2010 14:08            

The phase modulation is intended for modulator frequencies in the audio range (the range of modulator frequencies that produce side-bands and timbral effects).

posted 12 February 2010 17:40            

thanks for that, much appreciated.

I had been using

!FreqLow hz + ( [LFO] L * !Mod nn)