How to build a psytrance bassline that rolls

In psytrance the bassline is half the groove. Kick and bass together make the rolling engine that keeps a dance floor moving for hours, and most of what separates a flat track from one that pulls you in happens in these two elements. Here is how to build one that works.

The pattern: kick, then bass

The classic psytrance bass plays on the 16th notes between the kicks. The kick lands on every beat, the bass fills the three 16ths after it: kick, bass, bass, bass. That pattern is called a rolling bass, and it is the backbone of full-on and much of progressive. A common variation leaves out one of the three notes, which gives a galloping feel.

The point is that kick and bass never sound at the same moment. That is what makes the low end clean and punchy at the same time, and it is also why the tail of the kick and the length of the bass notes matter so much.

The sound

Most psytrance basses start simple: one saw or square oscillator through a low-pass filter. The character comes from an envelope on the filter cutoff with a fast attack and a short decay, so every note gets a short, plucky bite and then closes again. Keep the amp envelope short as well, so each note ends before the next kick.

A little modulation keeps the line alive. Let an LFO or an automation lane move the cutoff or the envelope amount over several bars, or vary the velocity of the three notes slightly. Small changes are enough, because the pattern repeats for a long time and the listener notices every shift.

Sub and top layer

Many producers split the bass into two layers. A sine wave carries the sub, roughly the range below 100 Hz. A second layer with the filtered saw or square carries the bite in the low mids. Each layer gets its own job: the sub gives weight, the top layer gives the click and the movement you hear on small speakers.

Keep everything below about 120 Hz in mono. Stereo effects, wide chorus or reverb belong on the top layer at most, and even there in small doses. Reverb on the sub smears the low end.

Kick and bass in the mix

Tune the kick to the key of the track and choose the bass key so that the fundamental sits low but stays clear on a big system. Then fit the two together in time: shorten the kick tail or the bass attack until there is no overlap. Many producers also duck the bass with sidechain or a volume-shaping tool right where the kick hits, not for audible pumping but to keep the two from smearing into each other.

Saturation or light distortion on the top layer adds harmonics, which makes the bass audible on headphones and laptop speakers too. Compression is usually gentle here, because the short envelopes already keep the level even.

Check it like a DJ would

Compare your track at the same loudness with a few releases you like in the same style. Listen on a good system, on headphones and on a small speaker. If the bass disappears on the small speaker, the top layer needs more presence. If it booms on the big system, the sub is too loud or too long.

Then play the whole track from start to finish. A bassline that sounds great for eight bars can tire you out after six minutes. Small changes in the filter, the pattern or the note lengths at the right moments keep the energy up without breaking the flow.