Dialing Karnivool’s Monster Bass: Forrester Savell’s Amp Sim Tips

Getting a truly monstrous metal bass tone that sits perfectly in a dense mix, all while working in the box, can feel like a dark art. But what if you could get insights from someone who’s nailed it time and time again? We’re talking about Forrester Savell, the man behind the desk for bands like Karnivool, Dead Letter Circus, and Twelve Foot Ninja. Lucky for us, Forrester dropped some serious knowledge on how he crafts those powerful Karnivool bass sounds using amp sims. Spoiler: it’s not about finding one magic plugin.

This approach comes straight from Forrester’s Fast Track course on Nail The Mix, where he dives deep into mixing Karnivool’s track “Simple Boy.” Let’s break down his killer techniques for building a colossal bass tone from a simple DI.

The “Divide and Conquer” Strategy for Your Bass DI

Forget trying to make one amp sim do all the heavy lifting. Forrester’s core philosophy is to split that bass DI signal onto multiple tracks – usually three – and treat each one differently. Why? Because different amp sims excel at different things. By combining their strengths, you can create a far richer, more controlled, and ultimately bigger bass sound than you’d get from a single source.

Think of it like this: one track for the clean, foundational low-end, another for the aggressive midrange grind, and a third for that top-end sizzle and distortion. Each layer contributes its unique flavor.

Before you start slapping on plugins, Forrester routes these individual bass tracks to a master bass bus. This is crucial for controlling the overall volume of your combined bass tone and for any bus processing you might want to add later.

Building the Beast: Layer by Layer with Amp Sims

With the DI split and routed, it’s time to start shaping each layer. Forrester’s approach is methodical, focusing on what each track needs to bring to the party.

Layer 1: The Foundation – Clean Low End

First up, you need that solid, unwavering low-end. For this, Forrester often reaches for IK Multimedia Amplitube. He’s a long-time fan, especially of their Ampeg model emulations like the classic SVX. The goal here isn’t aggression; it’s about a nice, clean, fat bass sound that provides the weight.

• Actionable Tip: Start with a well-regarded clean bass amp sim. Don’t worry about distortion on this track; focus on warmth and fullness in the sub and low-mid frequencies.

Layer 2: The Grind – Top-End Distortion

Now for the grit. That aggressive, distorted character that helps the bass cut through roaring guitars often comes from a different type of amp sim. Interestingly, Forrester turns to a guitar amp sim for this: the Avid Eleven Mark II. Specifically, he uses the “DC Modern” amp model (which he notes is available in the free version of Eleven) paired with a “4×12 Classic 30” cabinet impulse, notionally miked with a ’57.

This layer provides the high-end grind and distortion. However, this can sometimes introduce unwanted fizziness. To combat this, Forrester adds an EQ plugin after the Eleven Mark II to gently roll off some of the extreme top-end harshness. This cleans up the distortion without losing its aggressive edge. If you’re looking to master your EQ techniques for metal, check out these strategies.

• Actionable Tip: Don’t be afraid to use guitar amp sims on bass for distortion. They can provide a unique character. Always listen for and tame any harsh “fizz” with a subsequent EQ.

Layer 3: The Punch – Mid-Range Definition

The final piece of Forrester’s initial three-track puzzle is the mid-range – that crucial area that gives the bass its “poke” and helps it translate on smaller speakers. This is where some experimentation often comes in.

Forrester first tried the SansAmp PSA-1 plugin, aiming to push the mids and sculpt the lows and highs. While a classic, it didn’t quite deliver the specific mid-forwardness he was after for this Karnivool track.

Next, he auditioned Waves GTR Amp, finding a preset that offered a more suitable mid-range character. This highlights an important lesson: don’t be afraid to swap out plugins if one isn’t hitting the mark. The goal is the sound, not loyalty to a specific tool. The Waves GTR provided a good starting point for that meaty mid-range. Later in his process, Forrester actually A/B’d this against Joey Sturgis Tones (JST) Toneforge Menace, which ultimately won the spot for its mid-range character in the final blend.

The Secret Weapon: Phase and Delay Alignment

Here’s where things get really interesting and where many home producers might miss a crucial step. When you combine multiple audio sources – whether they’re different mics on a real amp or, in this case, different amp sims processing the same DI – you must pay attention to phase and delay relationships.

Different plugins, even with your DAW’s automatic delay compensation, can introduce tiny timing discrepancies. These might seem small, but they can lead to phase cancellation, hollowing out your tone or causing weird frequency buildups.

Checking Basic Phase

During his experimentation with the Waves GTR amp for the mid-range layer, Forrester noticed something wasn’t quite gelling when combined with the other two amp sims. His solution? He inserted a basic EQ plugin after the Waves GTR and flipped the phase. The difference was immediate and significant, with the bass tone “coming to life.” This simple phase invert made the three amp sims work together instead of fighting each other.

Advanced Alignment with Sample Delay (Auto-Align)

Forrester takes phase and time alignment a step further, especially when he’s zeroing in on the final blend. He uses a powerful tool called Sound Radix Auto-Align.

Here’s his workflow with it:

1. Insert Auto-Align on each of the bass amp sim tracks.
2. Designate one track as the “master” (e.g., the Amplitube track providing the clean lows). Set its Auto-Align instance to send its signal.
3. Set the Auto-Align instances on the other bass tracks to receive the signal from the master track.
4. The plugin then attempts to automatically detect and correct timing differences.

However, Forrester points out that the automatic detection isn’t always the best-sounding option. This is where his manual trick comes in:

• The Manual Sweep Trick: He’ll manually drag the delay compensation (measured in samples) within Auto-Align on one of the “slave” tracks while listening to the combined bass tone. As you sweep the delay, you’ll hear a phasing or comb-filtering effect – the tone will sweep up and down. Forrester listens for the highest point of this phase sweep. This point, where the sound is fullest and most solid, is generally the most in-phase position. For the Toneforge Menace track, he found that around -50 samples, with the phase inverted, provided the best result.

He also notes that Pro Tools has a built-in Time Adjuster plugin for sample delay, but a key advantage of Auto-Align is its ability to apply negative delay, effectively moving a track slightly earlier in time if needed. Small adjustments to this sample delay can also be a subtle tonal shaping tool, affecting the high-frequency interaction between the layers.

The Shootout: Making the Final Call

Once he had promising candidates for each layer, Forrester didn’t just settle. He conducted a shootout, particularly for that crucial mid-range track, comparing the phase-corrected Waves GTR against the JST Toneforge Menace (which also had its delay fine-tuned with Auto-Align).

His method for a fair A/B comparison:

1. Listen in the Mix: Don’t solo the bass. You need to hear how it interacts with the drums, guitars, and everything else.
2. Use a Loop: Find a representative section of the song and loop it. This gives your ears a consistent reference, making subtle differences easier to perceive.
3. Quick Switching: Mute and unmute the tracks you’re comparing rapidly to highlight the tonal changes.

In this case, the JST Toneforge Menace won out for the mid-range layer. It provided the necessary meat and poke without being overly aggressive in the mids like the Waves GTR felt in context.

The Final Monster Bass Tone Recipe (So Far)

After all this tweaking and careful listening, Forrester Savell arrived at a powerful, multi-layered bass tone for the Karnivool track using:

1. Clean Lows: IK Multimedia Amplitube (Ampeg SVX or similar)
2. High-End Grit: Avid Eleven Mark II (DC Modern) + EQ to tame fizz
3. Meaty Mid-Range: JST Toneforge Menace + Sound Radix Auto-Align for precise phase/delay

This three-pronged amp sim attack, meticulously blended and phase-aligned, creates a bass tone that is rich, defined, and ready to hold down the low end in a heavy mix.

Want to Go Deeper? Re-Amping & Beyond

This detailed amp sim strategy is just one part of Forrester Savell’s complete bass mixing workflow. In the full Karnivool “Simple Boy” mixing Fast Track on Nail The Mix, he takes it even further, showing how he incorporates hardware pedals by re-amping the DI and blending that back in, discusses advanced frequency splitting for ultimate control, and applies crucial compression techniques for metal bass.

These techniques – layering amp sims, meticulous phase and delay alignment, and careful A/B comparisons – are things you can start applying to your own productions right now. Experiment with the plugins you have, listen critically, and don’t be afraid to try unconventional combinations.

If you’re serious about taking your metal productions to the next level, seeing how pros like Forrester Savell build their tones from the ground up is invaluable. At Nail The Mix, you get exactly that: access to real multitracks from huge metal bands and hours of instruction from the producers who mixed them. It’s more than just presets; it’s about understanding the why behind every decision. Ready to unlock your sound and mix modern metal beyond presets? Check out the full session here as part of our URM enhanced program.