How to Use Serum FX Rack for Post-Processing

Most producers know Serum for its incredible oscillators and wavetable engine. But the built-in FX rack is a seriously underrated tool that can handle a lot of your post-processing without ever leaving the plugin. From distortion and compression to reverb and EQ, Serum’s FX rack can replace several external plugins in your chain.

In this guide, we cover how to get the most out of every effect in Serum’s FX rack and how to use them for professional-sounding post-processing.

Understanding the FX Rack Signal Flow

Before diving into individual effects, it is important to understand how the FX rack works. Effects are processed from top to bottom in the order they appear. You can drag effects up and down to reorder them, and the order makes a huge difference to the final sound.

For example, putting distortion before reverb creates a completely different result than reverb before distortion. Distortion before reverb gives you a distorted sound in a space. Reverb before distortion gives you a washy, chaotic texture. Both are useful, but for very different purposes.

Distortion

Serum’s distortion module offers multiple distortion types, and each one has a distinct character:

• Tube: Warm, analog-style saturation. Great for adding subtle warmth to pads or gentle grit to leads
• Soft Clip: Smooth, transparent saturation that is useful on almost anything. A safe choice when you want to add presence without obvious distortion
• Hard Clip: Aggressive digital distortion. Perfect for dubstep and riddim bass sounds where you want maximum aggression
• Lin Fold: Linear wavefolder that creates complex harmonics. Excellent for creating metallic, bell-like textures from simple waveforms
• Sine Fold: Sine wavefolder with a smoother character than Lin Fold. Creates rich, organic overtones
• Bit Reduce: Reduces bit depth for a lo-fi, crunchy digital character. Use sparingly for texture
• Downsample: Reduces sample rate for aliasing artifacts. Creates a retro, gritty digital sound

Distortion Tips

The Mix knob on the distortion module is your best friend. Instead of going full wet, try blending in distortion at 30-50% for a more controlled result. This is essentially parallel distortion within the synth, and it preserves some of the clean signal’s clarity while adding character.

Try using the filter before distortion (set it in the routing matrix) to only distort certain frequency ranges. This is a simple alternative to multiband distortion and keeps your low end clean.

Compressor

Serum’s built-in compressor is straightforward but effective. It has the standard controls: threshold, ratio, attack, release, and gain.

For bass sounds, try these settings as a starting point:

• Threshold: -15 to -20dB
• Ratio: 3:1 to 5:1
• Attack: 10-30ms
• Release: 100-200ms
• Gain: Adjust to compensate for volume reduction

The compressor is especially useful after distortion to tame any wild peaks that the distortion creates. It keeps everything controlled and prevents clipping.

Multiband Compressor (OTT-Style)

This is arguably the most-used effect in modern bass music production. Serum’s multiband compressor works similarly to the famous OTT preset from Ableton. It compresses quiet signals up and loud signals down across multiple frequency bands, creating that in-your-face, hyper-detailed sound.

• Amount: Start at 30-50%. Going to 100% sounds extremely processed and is only appropriate for specific styles
• Band adjustments: You can adjust the output level of each band (low, mid, high) to shape the tonal balance after compression

A common approach is to use the multiband compressor as the last effect in your chain, adding it after distortion and EQ to glue everything together and bring out detail.

Reverb

Serum’s reverb is simple but gets the job done for many applications. It works well for adding space to leads and pads without needing an external reverb plugin.

• Size: Controls the perceived room size. Smaller values for tight spaces, larger for halls and chambers
• Decay: How long the reverb tail lasts. For bass sounds, keep this short (under 1 second) to avoid muddying the low end
• Mix: The wet/dry balance. For most sounds, 10-30% mix is enough to add depth without washing things out
• Low Cut and High Cut: Essential for keeping reverb out of your sub frequencies and preventing harsh high-frequency buildup

Reverb for Bass Music

For dubstep and bass music, use reverb sparingly on bass sounds. A little goes a long way. If you want spaciousness, try using a short reverb (0.5-1s decay) with a high-pass filter around 200Hz to keep the reverb out of the sub range entirely.

Delay

The delay module offers standard tempo-synced delays with feedback and filtering options.

• BPM Sync: Lock the delay time to your project tempo for rhythmic delays
• Feedback: Controls how many times the delay repeats. Higher values create longer, more ambient trails
• Filter: Roll off highs and lows from the delay repeats to keep them from cluttering your mix
• Ping Pong mode: Alternates delay repeats between left and right channels for a wide stereo effect

EQ

Serum’s EQ is a simple but useful parametric EQ with low shelf, peak, and high shelf bands. It is perfect for quick tonal shaping without leaving the plugin.

• Use the low shelf to reduce or boost sub frequencies
• Use the peak band to cut problem frequencies or boost presence in the mid-range
• Use the high shelf to add air or tame harshness

Hyper/Dimension

The Hyper and Dimension effects are stereo enhancement tools that add width and depth to your sounds.

• Hyper: Creates a chorus-like widening effect by detuning and spreading the signal. Great for making leads and pads sound huge
• Dimension: A more subtle stereo effect that adds depth without obvious modulation. Works well on bass sounds where you want width without pitch instability

Important note for bass music: always check your bass sounds in mono after adding stereo effects. Width effects can cause phase cancellation that weakens your bass when the track is played on a mono system.

Recommended FX Chain Orders

For Dubstep Bass

Distortion > EQ > Compressor > Multiband Compressor

For Leads

Distortion > Hyper/Dimension > Delay > Reverb > Compressor

For Pads

Reverb > Delay > Dimension > EQ > Compressor

Take Your Sounds Further

The FX rack is what separates basic Serum patches from professional-sounding ones. Our Serum preset packs make full use of the FX rack with carefully tuned effects chains that you can study and learn from.

For more tips on using Serum’s effects, the Splice blog regularly publishes excellent Serum tutorials and sound design guides.

Related Preset Packs

Looking for professional bass music presets? Check out these Serum preset packs:

• Dirty Bass Master Bundle Vol. 1 & 2