8 Quick Tips on Designing Synth Basses
If you create dance music, it's important to know how to create and tweak synth bass sounds. Here's a collection of eight short sound design tips about how to make better, stylish, and more versatile synth bass sounds.
1. Octave Stacking
To make my synth bass sound fatter, I use a polyphonic bassline and play two notes at once, spaced an octave apart. This means playing C2 and C3 simultaneously, instead of just C2 or C3 alone. If the note sounds strange, then go a couple of notes higher, or transpose the whole scale you are using.
A similar technique is to add a second oscillator tuned an octave below. Then you only need to play one note at a time.
With subtractive (analogue) synthesis, try combinations of different oscillators to achieve the character that you want. Different waves have different perceived loudness and brightness. The order from the simplest to the fullest is: sine, triangle, square, saw.
For a more pronounced effect, turn on oscillator sync, which will also increase the preceived amplitude of the sound. Some synths have special oscillators like the trapezoidal wave, but you can make it with combining square and saw. Keep in mind you can fine tune squares or pulses even further tuning pulse widths (in extreme cases it gives a nasal type sound).
Here are some ideas to try:
- square for low and square for high
- square + saw
- triangle + square
- triangle + saw
- sine + square
- sine + saw.
You can also use wavetables (with synths like Massive, Dune, Thor, Synthmaster, Zebra, Largo, PPG Wave), which are custom-made (custom harmonic content), unique waves. Of course for bass, choose waveforms richer in harmonics (check that on a spectrum analyzer), and changing the waveforms live.
When adding modulatiion (for example with an LFO), some waveforms will sound weaker. To solve this, check all the waveforms, and choose the ones which sound best for your needs. DAW automation can help with this.
FM synthesis can create more complex timbres than subtractive/analogue synthesis. Start by using sine and triangle waves for operators, then carefully start to use richer waveforms.
For example, if you modulate a sine wave with a sine wave (the simplest waveform), and increase the amount of modulation, you get a robotic or flanged sound. But you have to experiment with the settings to achieve a full character. Take care: weak spots can occur depending on the sound.
White noise has random frequencies across the whole spectrum, so it differs from oscillators and operators (no cycle - no repeat). In itself, noise is very boring to listen to. But by adding a small amount of it to your bass sound, you'll get more attack, fullness and richness.
White and pink are the common types of noise. Note that there is a difference between digital- and analogue-generated noise.
- White noise—same amount of level across the frequency spectrum
- Pink noise—the amplitude is weaker for higher frequencies
- Red (brown) noise—similar to pink, but less high content
- Grey noise—noise with an inverted spectrum curve.
To shape the sound, we can subtract harmonics with filters. We are dealing with bass in this article, so to give the sound more style, consider using an uncommon type of low pass filter.
Filters listed in 'standard filters' below will sound you very familiar. You might try other types as well to get a new feel. These all have to be heard to decide which to choose.
- Standard filters: Moog ladder, Oberheim SEM, 303
- More esoteric ones: ARP, WASP, Serge, EMS, Korg MS-10, MS-20, Steiner Parker
- Formant filters to give a vocal-esque feel
- Vactrol-based filters to get a plucky-woody sound (think Buchla).
It works as a synergy, so small bits of modulation can give very organic or live feel to a sound. You can make or break a bass with the amount and type of modulation you use.
A common type of modulation is to modify the filter cutoff, which can make the 'wah' sound very popular in dubstep and drum and bass. Slow pitch modulation (below 20 Hz) is also called vibrato.
- Pulse width modulation (PWM) when using square or pulse waves
- Waveform modulation when using wavetables
- Pitch modulation (frequency modulation)
- Audio rate or cross modulation (fast frequency modulation)
- Amplitude modulation (AM)
- Filter cutoff modulation, also consider resonance modulation for more effect.
To make the sound wider and fatter, you can season the sound even further with FX. EQ defines the tone (dark, bright, strange), saturation and distortion usually make a dirtier top end. Chorus and reverb can give you more stereo presence, but be careful when using it.
A common practice is when making complex basses is to use mono and stereo basses in a way that, when a stereo bass is used, then the next one will be mono bass and vice versa. So you can change its type from note to note. This adds more drama as well.
Compression can give you more attack and top end. When applying compression, try different types. We are talking about bass here, but that doesn't mean you have to always use tube-based compression. Why not try a VCA or FET?
- Compression (try VCA, FET, tube and opto types)
- Saturation and distortion
- Slight chorus and reverb, with filtering the low end mud.
8. Outboard Gear
If you're making sounds only in the box (ITB), hardware effects are a nice add-on. For reasonably cheap solutions, think guitar pedals: distortion, fuzz, compression and so on. You can try tube-based effects as well, but at a slightly higher price.
These days, proper synth basses are more important than ever—especially in dance music. It is necessary to know how to shape and enhance every parameter of the sound. Combine these tips as you like, and have fun!