PreSonus Blog

De-Esser Meets Amp Sims

Some guitarists feel amp sims don’t sound “warm” or “smooth,” but that can also be an issue with physical amps. This is why guitar players often turn down a guitar’s tone control to reduce highs. Distortion adds harmonics, so distorting highs just piles on more highs.

Single-coil pickups have a naturally brighter sound than humbuckers, so they tend to highlight potential high-frequency issues. One fix is a narrow, sharp cut at a specific frequency to sweeten the sound, as described in The Ampire Sweetener. However, now that version 6 has a De-Esser, we can use its dynamic response for “intelligent” sweetening.

How the De-Esser Works

A de-esser reduces excessive vocal sibilants (“s” sounds) by compressing only high frequencies. This lowers the sibilants’ level, while leaving the rest of the vocal relatively untouched.

Although the EQ3’s dynamic EQ can produce this effect, for guitar the De-Esser is more plug-and-play. The controls that narrow in on “ess” sounds make it easy to narrow in on the guitar sounds you want to tame.

How to Set the Controls

The de-esser can go either before or after an amp sim. Placing the de-esser after the sim can clean up the highs that the sim generates, but pre-amp sim placement lets you suppress high frequencies before they’re distorted (fig. 1). Try both options—the effect is quite different.

Figure 1: Typical pre-amp sim settings for the De-Esser.

To zero in on the best pre-amp sim De-Esser settings:

1. Loop your guitar, and listen to the amp sim output.

2. Set Range = Full, Shape = Narrow, and S-Reduction to 0.00.

3. Enable Listen, and vary the Frequency control. The sound will be nasty, because you’re trying to highlight where an amp sim performs at its worst. Find the most objectionable-sounding frequency, which will likely be around 4 to 7 kHz.

4. Turn off Listen, and turn S-Reduction counter-clockwise to reduce the highs feeding the amp.

In the audio example, the first part doesn’t have the De-Esser inserted. The second part does. Remember that the De-Esser functions dynamically, so the effect will be most obvious on the loudest chords. In this example, compare the last two measures of each part. You’ll hear how the de-esser in the second part removes that slight high-frequency “edge.”

Post-Amp Sim De-Essing

When inserted after the amp sim, the De-Esser becomes more of an effect that can modify the amp sim sound. I’d recommend the following to become familiar with this effect:

1. Loop your guitar, and listen to the amp sim output.

2. Start with Range = Full, Shape = Narrow, and S-Reduction at -60.00.

3. Use the Frequency control to dial in the high-frequency range you want to reduce.

4. Vary the S-Reduction control for the amount of attenuation.

For more of a humbucker character with single-coil pickups, choose Wide instead of Narrow. Wide splits the audio into two bands, and reduces levels above the Frequency setting. Narrow splits the audio into three bands, and reduces levels in the middle band. Then, vary the Frequency control. The optimum setting will likely be at 6 kHz and below (fig. 2). Again, choose the amount of high-frequency attenuation with the S-Reduction control.

Figure 2: Settings for a heavier, humbucking-type distortion sound.

Final Thoughts

Whether to insert the De-Esser pre- or post-amp sim depends on the amp sim. The audio example uses Ampire, which is one of the better amp sims. Inserting the De-Esser before the amp is really all that’s needed. Sims with “nastier” high frequencies benefit more from post-amp placement, because the De-Esser can give a more drastic effect.

In any case, the above suggested settings are starting points. The best approach is to loop your guitar, enable your amp sim, and play with the controls. You might be surprised at how the De-Esser can add the extra touch that’s needed to turn an amp sim from good to great.