Filters...And What Are They?
I have had one or two emails regarding the use of the various filter types that you tend to find on soft synths etc. They are low-cut and high pass filters, and vice versa.
High cut and Low pass (LP) filters are one of the same. They remove high frequency content from the frequencer cut-off frequency (find the freq knob, and turn it up and down. You will find that the sound becomes brighter or darker as the output rises or falls). With a HP (high pass/ low-cut) button, the low frequencies are now being removed. BP or Band Pass uses a high pass and a low pass filter- so only a small amount of frequencies within a certain range gets through.
An Auto-filter is also a Resonnance Filter. This means that the signal around the cut-off will be boosted as the resonnace control is increased. This is found in techno and dance tracks.
The rest of this mini tutorial uses the free SuperWaveP8 VST as an example. How to use it, download it etc can be found here: SuperWave Tutorial.
If we have a look at SuperWave P8 we can put all this together. Go to PSB 80s Bass. Have a look at filter 1 envelope, and drop down the DEPTH to about 4. In filter 1 increase RESO to about 9. Play some notes, then increase the CUTOFF as you play. if you notice on the right hand side. of filter 1, you see LPF, BPF, and HPF (low, high and band pass filters). If you bring down CUTOFF to about 4, and then press TYPE, you shall find your sound changing- chopping off low and high frequencies.
But we still have a bass sound in the background? Yes, but that is because we have two sounds running at the same time- filter 2. So if we give filter 2 exactly the same values of filter one, then we get true high and low pass effects. With messing around, we could have one "synth sound" running as HP and one running as LP, which gives us a bassier synth sound.
If you want to have a go at my free Synth tutorial, it can be found here: Synth Tutorial.
Click to go back to the music article page.