Without proper processing, drums can sound dull and lifeless. Moreover, if the drums have emphasized high frequencies, they may sound quite artificial. It’s not a secret that processing your drum sounds with proper “warm” saturation can enormously help, although some saturation effect units sound way better than others. Having this in mind, in the next tutorial, we will show you how to get vivid drums by using harmonic saturation.

As usual, we have previously made a short sequence in the SoundBridge: DAW, where the drum section will be the point of our interest. Let’s start by listening to our sequence with the unprocessed drum section.


~Full Mix – Unprocessed Drum Section


Group the Drums


As we can hear from the audio example, the drum section sounds ok, but it could sound a bit more fat and have some accent on the mid frequencies. We will start by grouping the Percussions and Hi-Hats channels for easier control.



SPL Twin Tube


There are many options on the market regarding quality saturation effects, but for the sake of this tutorial, we have chosen the TwinTube designed by SPL. We will add a fresh instance of it to the newly created Drum Section group to start with.



The TwinTube module is the first combination of two essential tube effects in a single processor, that is, saturation effects along with harmonics processing. Both stages work separately from each other and are based on individual processing stages. The effects can, therefore, not only be applied both individually or separately but also in common. In the original analog design, the saturation effects are generated through the tube being pushed to and beyond its normal operating limits. In contrast to semiconductors, a tube thus pushed to such levels does not clip from a certain level, approaching more gradually its level limits and thereby producing its typical tonal result, which in audio signal processing can have such often profitable aural effects.


The Interface


The TwinTube interface looks simple and straightforward. But there is powerful processing hidden between those few knobs.




Starting from the top part of the interface, we can see a “HARMONICS” control. The HARMONICS control results in an enrichment of the overtone range for a chosen fundamental tone. The tonal result is an intensification of the presence that produces a fresher, silky, and more brilliant aural image. Similarly, the signal’s spatial qualities gain intensity.

Below there are two HARMONICS switches. With the HARMONICS switches, you choose the frequency range of the fundamental tone area that should be processed with the HARMONICS control. What’s more, there are four available frequency ranges. For reasons of space, the frequency values are rounded for the front lettering.




Next, we can see a big knob which is representing the SATURATION control. The SATURATION control offers a wide range of effects intensity from subtle to brutal harmonic distortion. Aside from harmonic tube distortion, the accompanying tube limiting effect should also be considered.


Storing the Adjustments


Lastly, you will notice the SETTINGS A, B, C, and D on the right side of the interface. The settings feature allows storing four different sets of adjustments (A, B, C, D).  Much faster than with the usual save and recall preset dialogues, the respective current setting is stored automatically when you switch to another setting – to recall previous settings by just one click.


Practical Examples


After a brief introduction of TwinTube and its main control parameters, let us move to some practical examples. We will first listen to our Drum Section group unprocessed, then processed with TwinTube and finally how the Drum Section treated with TwinTube sounds in context with other elements of the mix.


~Drum Section Group – Unprocessed

~Drum Section Group – Processed with TwinTube

~Full Mix – Drum Section – Processed with TwinTube


Feel free to download the project file here.