Operation

This section describes how to build your tone using the specific controls of each module. An overview of the modules and their controls is available in the previous chapter. A complete list of the parameters exposed by the plug-in is available in the next section.

Getting Started

Explore the Presets

As explained earlier, the best way to get started is to explore existing presets first, then modify the tone by switching presets provided for each module, or to morph between presets that you like using tone maps. The plug-in contains hundreds of presets and sub presets so that it can be used almost exclusively with presets (and module presets) if you do not wish to get into the details of editing. Also, tone maps give you access to an infinite number of tones by letting you morph between these existing presets.

Note about levels: since distortion is highly dependent on the input level and the content of the input signal, you may have to adjust the input and output gains of the plug-in when using using presets on your own material.

As a rule of thumb, you should try to make sure that the input level never exceeds 0 dB and that the output brickwall limiter is never triggered (unless its pumping effect is desired).

Tip: adjust Drive and Dynamics. It is not because an existing preset was set for "crunch" that it won't work well when pushing the drive to 11 or reducing it to get a clean sound. Also, feel free to experiment with the "Dynamics" setting: the preset will react very differently depending on the incoming sound and the way you play.

Editing Presets

If a preset is close to the desired effect but note quite, you can first try to tweak the parameters available in easy mode. It should give you enough control to adjust the tone in most cases.

For finer tuning, you can turn the modules you want to change into edit mode and access the more advanced parameters. Remember that you can save your changes as new presets for each module and reuse them later.

Creating a Sound from Scratch

Once you are familiar with each module and the impact of its parameter on the tone, you may want to create new sounds from scratch.

The exact methodology depends on the type of sounds you are looking for and the instrument to process. In general, you will likely want to start with a post-fiter that (at least) reduces higher frequencies (see the "Lowpass" preset). For guitar sounds, using a cabinet or amp preset for the post-filter will probably be a good choice, since it has a very large impact on the overall sound.

Just remember that all three module have a deep interaction with each other, so any drastic change on one of them may require some more editing on other. For example, boosting frequencies with the pre-filter for emphasis is likely to require some compensation on the post filter.

Using Tone Maps

As explained earlier, tone maps are a great starting point to explore the existing presets and create your own tone without dealing with the details of Destructor:

Tip: remember that using locks on each module, or browsing maps for individual modules, you can affect some parts only of the processing chain. If you are almost happy with your tone but feel that the post filtering is not adequate, use post-filter tone maps, or lock all other sections while navigating main presets maps. Note that since individual module maps affect much less parameters than global maps, they can be more intuitive to use.

Tip: remember that the drive parameter is not used in maps. So if you are looking for clean tones, adjust the drive accordingly (or simply click on one preset in the map to get a good starting point).

Exploring

In order to explore presets without having to listen to them all one by one, add a large number of presets to a map, and check their location: presets that are close to each other will sound similar, while others will produce different tones (drive parameter aside). It is a good way to find out quickly presets that you may like or dislike, based on their location compared to presets that you already know.

Tip: when maps contain many presets, enlarge the window and zoom to get more control over the location of cursor, as changes in tone may be drastic even when moving very slowly.

Simple Morphing

If you like some presets and want to explore what tones you can get between them, gather them into a map (keep it preferably simple, like 3 to 5 presets) and move the cursor around. You might be very surprised by the results!

Use the "Locate" Command

Typical (References) Maps

In the built-in factory maps, you will find "typical" guitar and bass preamp settings maps. We have created these after analyzing the shape of hundreds of possible settings for the pre-filter in guitar amps, and they are a good representation of the typical tones that can be found for the preamp section for guitar and bass amp tones.

Use these maps to create your own amp tones from scratch quite intuitively by moving the cursor between these typical tones (with a given Destruction and Post-Filter setup)

You can create similar maps for yourself for all modules, using your own typical tones that will set the boundaries for the map, and let you explore new tones in your own territory.

Another interesting way of using typical maps is to use them as an reference to explore existing presets: load the typical map then load another preset into it to see how it compares to your reference tones. It may be closer to them than you think (or completely off the map).

Learn From Tone Maps

While exporing tones thru the maps, open the modules in "full edit" mode and observe how the curves move: this will help you learn how the shapes of the various curves influence the tone.

Project Tones Onto Your Maps

When you create a tone map with your favorite settings, you create a playground with reference tones that you like. The tones available on the map, while (almost) in infinite number, is reduced compared to the overall tones that you can create with the plug-in. Creating tones on the map is like adding constraints to the plug-in so that it stays in a particular area of the space of all possible tones, which are more likely to please you.

So once you have created a tone map that you like, you may want to explore other presets that are not on the map and use the "locate" button to project them onto this map: it will create a new tone that's located on your own playground, using the current settings as a starting point.

You can use the same idea with the random function: create a random preset and project it onto one of your maps. It is like choosing a random location between your favorite tones.

Try it out: you might get surprisingly good tones out of it!

Using the Destruction Module

The destruction module is the core of the Destructor plug-in. This is where harmonics are generated and what causes the distortion.

Setting Up the Shaper Curve

The first step is to choose the shape of the destruction curve: load a shape preset or edit the curve using the white dots or arrows. Keep in mind that the shape of the curve continues with the same slope beyond 0dB:

This sets the behavior of the Destruction module when fed with signals above 0 db (overshoots).

dots vs arrow when increasing drive.

Tip: while changing the shape of the curve, you should keep an eye on the reference sine wave to check an audio signal is actually affected.

Shaper Curve & Sound

As a general rule, the more edges in the shaper curve, the more harmonics, and the harsher the distortion. A quick look at the shape of the transformed sine wave in the following examples will give you the idea:

From soft tube saturation to harsh digital distortion

You can use the "smooth" parameter to reduce edges and soften higher order harmonics for a more analog-like sound.

Symmetrical vs Asymmetrical

The plug-in lets you setup symmetrical or asymmetrical distortion in several ways: first, increasing the rectify parameter will produce an asymmetrical curve. Also, in non-symmetric mode, additional points can be specified for the lower part of the shaper:

Asymetric clipping is known to produce mainly even order harmonics, whereas symmetric clipping emphasizes odd harmonics. The difference is subtle but noticeable (especially with post-filter disabled). Try by yourself and check if you can hear the difference.

As an example, tube amplifiers using several stages with rectification are known to be asymmetrical, whereas most designs with transistors or early single stage tube amplifiers are likely to be more symmetrical. However, this is not a general rule (typically, fuzz pedals use transistors to produce highly asymmetrical clipping).

Also, what makes the biggest difference between such types of distortion circuits is not the symmetry of the shape but its dynamics, as explained later in this manual.

The Drive Parameter

Increasing the drive offsets the destruction curve towards the origin as if the input gain was increased, and produces more distortion, without necessarily increasing the peak levels (it depends on the shape of the curve, though):

Drive, more drive, and much mor drive

Tip: a good practice is to setup the shape in such a way that the distortion is barely noticeable when the drive is set to 0, so that you can then use the its entire range efficiently (remember, it goes to 11!).

Adding Dynamics

As mentioned earlier, the dynamics of the destruction shape is what makes the biggest difference between distortion tones, especially for very expressive instruments such as guitars, and even more for small amounts of distortion ("crunch sounds").

If you haven't experimented with shape dynamics yet, you may have noticed at this stage that static distortion can sound flat and tiring in some cases.

Adding dynamics to the destruction process can greatly improve the distortion and the feeling while playing an instrument into the plug-in, simply because it implies a direct interaction between the instrument and the distortion effect.

Very basically, dynamics control is a system that defines how much the curve affects the signal - just like the "Shape Mix" parameter - based on the measured level ("envelope") of the signal.

Shape Dynamics Controls

Shape dynamics is impacted by four categories of parameters, which are similar to what compressors usually offer:

The source: the source selector lets you choose which signal affects the destruction curve. You may want to use the input signal before the compressor and gate if you want finer control from the instrument, or directly at the preamp stage, if you prefer to simulate the dynamics effect of electronic circuits. The external side chain source lets you trigger the distortion from another audio source, and produces very interesting side chain distortion effects.

The range: this is the amount of dynamics applied to the curve. This is the main control to choose how much the curve may change over time, based on the signal envelope coming from the selected source. When it is set to 100%, there will be no distortion at all (straight curve) when the envelope goes below the threshold (or above, if the ceiling is lower than the threshold).

The envelope settings: just like for a compressor, the attack time sets how fast the plug-in reacts to level increases, whereas the release time sets how fast the plug-in will decrease its envelope when the signal level drops. For each of these times, the shape parameter changes the shape of the attack and release curves:

Example: influence of the shape parameter on release

For positive values, the overall time will be increased, because the envelope follower becomes slower and slower. Whereas for negative values, the overall time will be reduced, because the envelope follower gets faster and faster. You can experiment and check the envelope meter on the right to visualize the impact of these parameters.

If you are familiar with our dynamics processing plug-ins, the behavior is very similar.

The threshold ("cold") and ceiling ("hot"): when the envelope meter reaches the ceiling (and beyond), the destruction curve is the same as if no dynamics was applied (100% wet). When the envelope reaches the threshold (and beyond), the distortion is reduced by the amount specified by the range parameter.

The green curve on the graph reflects these changes in real time. The threshold can be set below or above the ceiling, which simply reverts the effect: ceiling above threshold means more distortion when the signal gets louder, while ceiling below threshold means more distortion when the signal gets quieter.

Shape Dynamics Examples

Many of the guitar presets use a dynamic destruction curve (check out the crunch section) to replicate the feeling of tube distortion, which usually includes some kind of compression.

You can even simulate analog compressors using gentle distortion curves that adjust the gain dynamically and produce very few harmonics. It is also possible to create custom gates, expanders etc.

When setting up the threshold and ceiling in reverse mode and with large range values, you can also create interesting effects where the distortion only happens on the tail of the sound, when it gets quieter (see the "Reverse" presets).

And do not forget the side chain applications too!

Adding Phase Shift

Phase shifting has two types of impacts: first, with high amounts of phase shift (10 and beyond), smearing will start to be audible around the center frequency, a bit similar to a sweeping filter. Second, it will produce phase cancellation effects between the dry and wet signals when blended together using the mix knob.

The latter is a typical effect used in analog distortion circuits that can produce very interesting distortion tones.

Oversampling

As described earlier, you can use oversampling to improve the quality of the distortion and avoid aliasing. Oversampling increases audio quality but uses more CPU, so this is a tradeoff between quality and performance. Further more, at higher sample rates the difference may not be audible, depending on the audio signal and the amount of distortion.

Pre and Post Filters

The pre and post filter are similar to parametric equalizers, but with several twists: emphasis and post filtering steps often require radical settings compared to what you would use an EQ for.

Comb Filters

You may have noticed the presence of a comb filter, in addition to usual cut, peak and shelving filters:

It can be used to add color to the sound (most often on the post filter, but not only). A typical use case is when you want to replicate the phase cancellation effects produced by room or cabinet reflections, or the combination of several microphones.

Impulse Reponses

With version 1.4, you can load your own impulse responses in both the pre and post filters, and manipulate them with the shift and mix controls:

Impulse responses let you capture the exact response of a system (guitar cabinet, room reverb, ...) and reuse it as a filter. You can import them to add color to the pre and post filtering stages, or replicate the exact behavior of an existing component. You can find many free and commercial impulse response libraries including guitar cabinets, reverbs and other types of filters.

Note: there is no limitation on the length of impulse reponses that you can load. You should however be aware that longer impulse responses consume more CPU.

Easy Mode

Also, when building a filter shape to be reused in "easy" mode, keep in mind that the three pink filters as well as the hi cut filter will define how the LOW, MID, TREBLE and TONE controls affect the signal.

Using the Gate and Compressor

While the gate and compressor at the input of the signal chain can be used for creative purposes (check out some of the radical factory presets!), their main purpose is to control the dynamics at the input of the plug-in: you will usually setup the gate to catch the noise, and the compressor to limit the dynamics: for heavy distortion, pre-compression is often fully part of the tone.

Reference Curves and Tone Matching

Both the pre and post filters give you the ability to load reference filter curves that have been measured using Blue Cat's FreqAnalyst Multi, as shown for example in this tutorial:

Approximating the rsponse of a cabinet with the post filter

You can create a filter curve that mimics the response of the measured gear. To get the perfect tone, the match is not required to be exact: you just need to make sure that the main characteristics of the response are reproduced. Keep in mind that the measuring process may also add its own artifacts - typically room interferences when measuring cabinets.

Also, the idea here is to use such references as a starting point, to build your own tone. If you really need an exact replica of the frequency response, you will probably want to use an impulse response instead.

Note: if you are measuring gear such as guitar amplifiers, you will need to make sure that you can measure the preamp (for the pre-filter), and the power-amp / cabinet combination (for the post filter) separately.

Chaining Several Instances

Using a plug-in chainer such as Blue Cat's PatchWork or when inside Axiom (or directly in your DAW), you can chain several instances of the plug-in to create different tones. For example you can try a pedal preset in front of an amp preset to create a very high gain tone on guitars.

Tip: very high gain guitar tones will typically require two distortion stages, with the first stage using simpler filtering (usually a simple high cut filter is enough).