Nowadays, in a lot of electronic dance music one can find themselves working with a very busy mix-down. Drums are usually so powerful and bright, background FX can be so prominent, and vocals can fill the spectrum from top to bottom. Sometimes, it can seem that we seldom have room for much else.
So how do we create a bass or synth sound stack that covers the full frequency spectrum and acts as the main riff of the track while standing up to the rest of the elements in the mix? Layering is one of the most effective techniques!
Layering Synths: A Crash Course
The goal here is to combine various sounds all with similar modulation and ‘movement’ but operating in different frequency ranges.
When creating these full-range sounds it is important to understand the role of each layer. Make sure each part of the sound is serving a purpose.
Firstly, each layer should be fundamentally operating prominently in a particular frequency range. By fundamentally, I mean the majority of the frequency content should be operating in this area.
Typically, this would be a case of three bands, low frequencies (0-100 Hz). Mid-range frequencies (roughly 100-2000 Hz) and high frequencies (2000 Hz and above). However, I find it is much more effective to divide the layers into four bands:
Sub – (0-100 Hz)
Low Mid – (100-500 Hz)
High Mid – (500 Hz – 2000 Hz)
Highs – (2000 Hz and above)
So because we’ve already found a frequency range for each layer, it doesn’t matter so much if the layers are similar in other ways. In fact, that’s kind of the point for what we are doing here.
The sub-bass is operating in the lowest-frequency band, it is the foundation of the layer and it is what gives the sound its rumble and energy when translated to a capable medium. It can be tricky to pick out the musical pitch of sub-bass, it’s something we tend to feel more than hear.
Modern producers don’t need to be reminded about the importance of sub-bass for EDM, trap, and virtually any popular electronic music.
The low mids are important to give the sound a particular power, it operates just above the sub bass but also not high enough to be completely distinguishable to the ear. Without it, I find that the stack can sound almost hollow or far-away.
I hear many mix-downs these days where the producer or engineer has appeared to neglect this band and instantly I perceive the bass/synth to be ‘weak’ or ’empty’. Also, by getting this right it allows the sound to translate over to mediums without the ability to re-create sub frequencies (Mobile phone, portable speakers) and still sound like a low-energy bass sound.
Here is where you will hear the main characteristics of the stack. This layer is where the human ear is able to distinguish sound most easily and this is where you will find the higher tonal harmonics that give the sound its musical personality.
The high range band is where the stack gets its presence and sheen. It is also where you can start to focus on the stereo image and begin to apply some width to really open the sound up across the imagery spectrum.
It is important to get this layer right in terms of balance as with too many high frequencies and you can quickly find yourself wrestling with other bright elements in the mix-down. But I find neglecting this layer can leave the final result sounding slightly dull and lost.
This technique can be applied to various different sounds with different characteristics, but it is important to remember that overall ‘movement’ of each layer needs to be coherent. That means the modulation sources should be kept identical so when each sound is played back together it is perceived as one sound.
For the sake of this tutorial I am going to talk about a moving bass-line or ‘wobbling bass‘.
When making a sound like this I generally find myself creating the main characteristic first, so that would be focusing on the high-mid range layer. I may create a 2 oscillator patch, with one oscillator acting as the fundamental foundation of the sound and another pitched up acting as the harmonic. Then, I may apply an LFO on both the amplitude of each oscillator and importantly – on the filter.
I now have the overall personality of the sound, this layer yields the tonality and harmonics within the stack. It is key to recognise that this is going to dictate the overall movement and evolution of the overall sound and therefore the rest of my layers must match up in terms of their modulations. The first thing to do is to save the LFO shape so we can easily access it in the patches for our other layers.
Or, you could just save time by simply duplicating the patch and reworking it, this is the approach I normally like to take.
I am now going to focus on my low mid layer, this is created in order to give extra energy in the lower register of the stack and allow it to translate well on to smaller audio systems.
To do this I have simply duplicated the patch, this way I know that my LFO shape will be completely accurate. All I have done here is switched the lower oscillator to a square wave and applied a low pass filter. This will limit any higher frequencies from the wave and leave me with a rounded off layer that is modulating in the same fashion as the previous patch.
My stack is now coming together, we have both the character and harmonics of the sound as well as the lower mid-range foundation. Now we just need to focus on the sub bass foundation and the higher end brightness of the high frequency register.
The sub layer is simply going to be a sine wave with no modulation applied to anything other than the OSC level. This gives the layer a simple movement that matches with the rest of the stack.
Sometimes I like to increase the level of the OSC just slightly to reduce the dynamics of the modulation or ‘wobble effect‘. This helps to make the sub sound more prominent in the stack.
The final layer I am going to create is the top layer, this is to emphasize the brightness and sheen of the sound by just focusing on the high frequencies.
I’ll start by duplicating the first patch or mid-range layer.
Then, I’ll activate only one oscillator and set that to a simple saw wave and then pitch it up by 1 octave.
By then turning up the voices to 8 and adding some detuning the result is a wide and high-pitched super-saw layer. By utilizing the noise oscillator and adding some white noise we can really fine-tune the high end ‘fizz’ with this layer.
I’ll finish by applying a high pass filter operating against each oscillator to remove any lower frequencies that may remain.
Equalization and Post Processing
We now have our four layers that form our full spectrum synth/bass stack. When played back they should be perceived as one thick and full sound.
The final touches to the stack would be to remove any unwanted frequencies from each layer to be sure that each one matches up nicely and doesn’t clash.
EQ is the most important tool to achieve this. Remember we have already used filters inside our synth layers to provide some separation, but further EQ can still help clean things up.
The sub should be low-passed to 90-100 Hz. Sometimes you may allow a sub patch to operate slightly higher between 1-200 Hz but because we have our designated low-mid layer this is unnecessary.
As we filter the low-mid layer it should already be fairly contained, but to be sure I like to apply a high-pass just above 100 Hz and a low-pass anywhere between 400-500 Hz, this should be fine-tuned accordingly.
This patch needs to be low-passed to remove any sub frequencies. But aside from that, it should be mixed to preference in tandem with the low-mid layer. It’s also important to make sure there isn’t too much high frequency information that is likely to clash with the “high” layer.
The high-frequency layer can be high-passed below 2000 Hz, removing any energy that may clash with the low-mid/high-mid layer.
The final step is all about levelling with the faders. It is important to get the amplitude right so every layer can be audible and effective. You may want to group all layers above the sub and add some subtle compression or saturation. Personally, I like to leave the sub untouched in this part of the process.
So with this simple technique, it is easy to build a full and thick sound. Build layers from the bottom up and make sure to match modulations within each patch. Be mindful of each layer’s purpose and be precise with levelling and EQ-ing to yield the best results!