Perfect Fifth Bassline Tutorial
Most of the music I listen to is quite old. However, when I am not at home, I hear a lot of music in the background. I noticed that many modern basslines sound like a major or minor triad with the middle note removed (which I later found out is a perfect fifth) and are additionally based on sawtooths. Today, I decided to attempt to make a patch for these basslines using Xpressive.

I used the formula (0.3 * saww(integrate(f))) + (0.3 * saww(integrate(f * semitone(7)))) + (0.3 * sinew(integrate(f * 0.5))) + (0.1 * last(9945)) within Xpressive.

What this does is generate two sawtooths at the pitch of the triggered key and then offsets one by 7 semitones, each at 30% power. 7 semitones is a perfect fifth. Another sine wave at 30% power is added one octave below the note of the key triggered (integrate(f * 0.5)) as the sub bass. Finally, I added an 8th-note delay using (0.1 * last(9945)) because (60 seconds / 133 BPM) * 44100 Hz = 19895 samples per beat. Since an 8th note is half a beat, 19895 / 2 = approximately 9945 samples per beat when rounded (it is actually 9947.5 samples).

Next, I added a low-pass filter and set cut-off and resonance with an instant attack, zero hold, 460 ms delay, 536 ms sustain, and 100 ms release, experimenting until it sounded like what I had imagined. I saturated and compressed the signal using the same principles of trial and error.

LMMS has no portamento or way that I know of to turn Xpressive into a monosynth. I noticed that there is a lot of portamento in these basslines, so I decided that any legato notes would have to be manually pitch bent using the pitch bend mode in the piano roll.

Next, I decided what chords and notes I would use. I used another patch named R3 which I created some time ago, which I realised sounds OK when used for piano type chords. Something that took me a while to learn after years of practice with no musical training is that a good way to create a house piano sequence is to work with two minor triads and play a repetition of inverted chords. More recently, I have been starting with two minor triads that sound OK, and then when I have them how I want, I replace them with the matching minor 9ths. I have no musical training whatsoever, so I do not follow scales.

I then decided to make the bassline follow (I don't know the correct terminology, as I have no formal musical training) my chords using monophonic notes derived from the chords at a lower octave. The final step was to add a sidechain compressor (something I need to pay more attention to, as I hardly do it) so that the bass volume lowers each time a kick is triggered. I used the Peak Controller on the kick drum FX tab and mapped the bass patch to an effects channel where the volume is controlled by the Peak Controller.

To be honest, since I don't listen to enough new music, the actual rhythm and notes of the bassline I wrote are probably not the best example. However, I think this patch is getting pretty close to what I am hearing in other music. Hopefully, this gives someone a start, or someone else might be able to get this perfect.