We've all heard (and possibly overheard) the classic LFO>Filter Frequency used in extensively in Dubstep, but LFOs can be used in many other creative ways. This quick tip will give you some ideas about how you can create interesting effects by applying LFOs to some other parameters on your synths/samplers. Most of the sounds in this tip have a slight 80s feel to them, but the techniques can be used in all musical styles.
Idea 1 - Volume
Applying an LFO to the volume of a synth or other instrument can add a really nice rhythmic quality to a sound. Listen to this classic synth sound:
In this example I have applied a sawtooth LFO to the volume, giving it a nice driving feel - notice how as you turn down the LFO amount the sound fills out again, adding a nice dynamic to the sequence. It also works really well in conjuction with the Filter envelope, emphasising the filtters movement.
Idea 2 - Pitch
In this example we will use the LFO to modulate the pitch of a synthesizer - usually you would do this by applying the LFO to the oscillators. Here is the sound as it stands:
Now I have added some subtle pitch wobble from the LFO - too much can result in the notes losing their definition but a small amount creates that lovely warm analogue imperfection.
Idea 3 - Rate
Here's an interesting one. Try modulating the rate of an LFO with another LFO - you can get some really crazy effects, brilliant for sound design... In this example my LFO is modulating the pitch of the synth, with another LFO modulating the rate of the first LFO - you get these great surges of pitch modulation...
Idea 4 - Using LFOs as a Trigger
In some programs such as Reason you can use an LFO to trigger the gate on a separate device. In this example I've routed the LFO on a subtractor into the gate input on a redrum unit which has a kick drum sample loaded.
You can hear how as the LFO rate is increased the drum hit is triggered more and more rapidly until self oscillation starts to occur and things get really glitchy! You can learn more about this technique and some advanced applications for it in my tutorial here.
Idea 5 - Experiment!
I've said this before but if you want to get unique and original sounds in your compositions one of the best tips I can give you is to experiment. Try applying LFOs to other LFOs, pan controls, wavetable positions, effects parameters, delay times, anything you can think of... You're not going to win every time but it's a great feeling when a crazy idea pays off.