EQ

Tonality EQ User Manual

Version 1.0.0 · Last updated March 2026

Overview

Tonality EQ is a creative, layer-based equalizer with perception-driven global controls. Rather than only offering traditional parametric bands, it provides four tonal shaping controls (Tone, Weight, Focus, Character) that address how you perceive frequency balance, plus a full ADSR envelope shaper for transient and sustain control.

Beneath the global controls sits a layer-based EQ system with five distinct filter modes: Surgical EQ, Balance EQ, Phase EQ, Harmonic EQ, and Overtone EQ. Each layer operates independently while the global controls shape the overall tonal character.

[Screenshot: Tonality EQ full interface]

Design Philosophy

Tonality EQ was built around three principles:

  • Perception first. The global controls are designed around how the ear perceives sound, not around technical filter parameters. Turning TONE clockwise makes things brighter and more exciting; turning it counter-clockwise makes things warmer and softer.
  • Zero-click DSP. All filter coefficients are fixed at initialization. Effect intensity is controlled through gain blending, not coefficient changes. This eliminates audible clicks when adjusting controls in real time.
  • Layered workflow. The EQ layer system lets you stack multiple filter approaches on the same signal, each addressing a different dimension of frequency shaping.

Signal Flow

Audio passes through Tonality EQ in this order:

  1. Input Gain — Level adjustment before processing
  2. Tone — Exciter / Tape Warmth shaping
  3. Weight — Sub-harmonic / Transient Punch
  4. Focus — Upper Mid / Lower Mid emphasis
  5. Character + Bias — Tape and Tube saturation (with optional 2x/4x oversampling)
  6. ADSR Envelope Shaper — Transient and sustain control
  7. Layer Stack — All active EQ layers in order
  8. Dry/Wet Mix — Parallel blend with the unprocessed signal
  9. Auto Gain / Output Trim — Level compensation and final gain

Tone

[Screenshot: TONE control]

TONE

Range: -1.0 (Tape Warmth) to +1.0 (Exciter) · Center: Neutral

Clockwise (Exciter): Extracts high-frequency content using a fixed high shelf at 4 kHz, then applies harmonic saturation to generate new overtones in the upper range. The result is added sparkle and presence without simply boosting the treble. At higher settings, the exciter generates audible harmonic shimmer.

Counter-clockwise (Tape Warmth): Applies gentle low-pass filtering combined with subtle tape-style saturation, including mild even-harmonic distortion. This progressively softens the high frequencies and adds a warm, slightly compressed character reminiscent of analog tape.

At center: No effect. The filter states are maintained internally so there is no click when the control is moved away from center.

Tip

Use small TONE values (0.1 to 0.3) for subtle tonal shaping. The exciter side is particularly effective on dull sources that need air without a traditional high-shelf boost.

Weight

[Screenshot: WEIGHT control]

WEIGHT

Range: -1.0 (Transient Punch) to +1.0 (Sub-harmonics) · Center: Neutral

Clockwise (Sub-harmonics): Adds low-frequency weight through two mechanisms. First, a fixed bell filter at 55 Hz (+6 dB) is crossfaded in, reinforcing the fundamental low end. Second, a sub-harmonic synthesizer generates content at approximately 40 Hz by rectifying the low-pass filtered signal and driving a sine oscillator. The sub-harmonic content fades as the control approaches maximum to avoid excessive rumble.

Counter-clockwise (Transient Punch): Emphasizes transient content using level-sensitive detection. Transient peaks are momentarily lifted to add punch and snap, while sub-frequency content is gently attenuated to tighten the low end.

At center: No effect. All internal filters continue processing to maintain state continuity.

Focus

[Screenshot: FOCUS control]

FOCUS

Range: -1.0 (Lower Mid Warmth) to +1.0 (Upper Mid Clarity) · Center: Neutral

Clockwise (Upper Mid Clarity): Crossfades toward a fixed bell filter at 2 kHz (+5.5 dB, Q 0.7). This brings forward the presence and clarity range, making vocals cut through a mix and giving guitars more bite.

Counter-clockwise (Lower Mid Warmth): Crossfades toward a fixed bell filter at 1 kHz (+5.5 dB, Q 0.6). This fills out the lower midrange, adding body and warmth to thin-sounding sources.

Both bell filters run continuously, and the Focus control blends between them. This ensures no clicks or artifacts when sweeping through the range.

Character + Bias

[Screenshot: CHARACTER and BIAS controls]

CHARACTER

Range: 0.0 (Off) to 1.0 (Full saturation)

Controls the overall intensity of the saturation stage. At zero, no saturation is applied. As the control is increased, the signal passes through a combined tape and tube saturation model with pre-saturation coloring (tape head bump at 80 Hz, tube mid bloom at 1500 Hz) and post-saturation gain compensation.

The saturation stage supports 2x and 4x oversampling to reduce aliasing at higher drive settings. Oversampling can be toggled in the plugin settings.

BIAS

Range: -1.0 (Pure Tape) to +1.0 (Pure Tube) · Center: 50/50 blend

Tape character (negative Bias): Soft, symmetric saturation via tanh waveshaping with moderate drive. Adds gentle 2nd and 3rd harmonics. Pre-saturation bass lift via head bump filter. Post-saturation high-frequency rolloff increases with drive, producing the classic analog tape warmth.

Tube character (positive Bias): Asymmetric clipping with a higher drive range. The positive signal half compresses gently while the negative half clips harder, producing strong even-harmonic (2nd harmonic) content. Pre-saturation midrange bloom at 1500 Hz adds the characteristic tube warmth. More dynamic and forward-sounding than the tape side.

Tip

Start with CHARACTER at 0.2-0.4 and sweep the BIAS to find the right character for your source. Tape tends to work well on full mixes and buses. Tube brings out vocals and solo instruments.

ADSR Envelope Shaper

[Screenshot: ADSR controls]

The ADSR section is a transient designer with full envelope control. It responds to short, punchy level changes and reshapes gain to emphasize or soften them.

ATTACK

Range: -1.0 (Soften transients) to +1.0 (Boost transients)

Controls how transient peaks are treated. Positive values boost detected transients for more punch and snap. Negative values attenuate transients for a softer, rounder sound. The detector listens for brief level changes and reacts according to the ATTACK, DECAY, and RELEASE settings.

DECAY

Range: 0.0 (1 ms, very fast) to 1.0 (400 ms, slow)

Controls how quickly the detector relaxes after a transient. Short decay values make the transient shaping more focused on the immediate attack. Longer values extend the effect into the early sustain portion of the sound.

SUSTAIN

Range: -1.0 (Reduce body) to +1.0 (Boost body)

Controls the gain applied to the sustained portion of the signal (the part that remains after transients). Positive values bring up the body and tail of sounds. Negative values reduce the sustain for a more transient-focused presentation.

RELEASE

Range: 0.0 (10 ms, very fast) to 1.0 (2000 ms, very slow)

Controls how quickly gain recovers between transients. Short release values reset quickly between hits. Long values create a more compressed, even dynamic profile. This interacts with DECAY to define the overall envelope shape.

Input/Output and Mix

INPUT GAIN (IN)

Range: dB

Adjusts the input level before any processing. Use this to drive the saturation stage harder or to attenuate hot signals before they reach the EQ layers.

OUTPUT TRIM (OUT)

Range: dB

Adjusts the final output level after all processing. Use in combination with Auto Gain for precise level matching.

DRY/WET MIX

Range: 0% (fully dry) to 100% (fully wet)

Blends the processed signal with the original dry signal in parallel. This is useful for parallel EQ and saturation techniques where you want to retain the natural dynamics while adding tonal color.

AUTO GAIN

On / Off

When enabled, Tonality EQ automatically compensates for perceived loudness changes caused by EQ and saturation. It uses a 400 ms RMS comparison between input and output levels with smooth attack/release tracking. This makes it easier to evaluate tonal changes without being biased by volume differences.

Layer System

[Screenshot: EQ layer stack]

The layer system is the parametric EQ core of Tonality EQ. Each layer is an independent EQ instance with its own bands, and layers are processed in series (top to bottom). You can add, remove, reorder, rename, and solo/mute individual layers.

By default, Tonality EQ creates five layers on initialization, one for each type. You can add more layers or remove ones you do not need.

Working with Layers

  • Add a layer: Click the add button and select the layer type.
  • Focus a layer: Click a layer to make it active in the frequency display. The focused layer's bands are editable in the main EQ view.
  • Remove a layer: Right-click (or use the context menu) to delete a layer.
  • Reorder layers: Drag layers up and down in the stack to change the processing order.

Layer Types

Surgical EQ

Traditional parametric EQ with precise frequency, gain, and Q controls. Use for corrective work: removing resonances, notching problem frequencies, or making surgical adjustments that need exact control.

Balance EQ

Broad, gentle EQ curves designed for overall tonal balance. Wider Q values and smoother slopes make it suited for shaping the general frequency profile without creating sharp peaks or dips.

Phase EQ

Phase-aligned filtering that shapes the frequency response while maintaining phase coherence. Useful when phase relationships matter, such as when processing parallel signals or when stacking EQ on multiple related tracks.

Harmonic EQ

Frequency-dependent harmonic enhancement. Rather than simply boosting a frequency, Harmonic EQ generates new harmonic content in the targeted region, adding richness and presence in a way that a linear EQ cannot.

Overtone EQ

Targets the overtone structure of the signal. Useful for enhancing or attenuating the harmonic series above a fundamental, which can change the perceived timbre without affecting the fundamental frequency itself.

Workflow Tips

1. Vocals: Cut Through a Dense Mix

  1. Set FOCUS to +0.4 to bring out upper-mid presence around 2 kHz.
  2. Add a small amount of TONE (around +0.2) for harmonic excitement in the air band.
  3. Use a Surgical EQ layer to notch any specific resonances in the 200-400 Hz range.
  4. If the vocal sounds harsh, dial BIAS slightly toward Tape to soften the upper harmonics.

2. Drums: Add Weight and Snap

  1. Set WEIGHT to -0.4 for transient punch to emphasize the attack of kicks and snares.
  2. Set ADSR Attack to +0.3 to further boost transient peaks.
  3. Set ADSR Sustain to -0.2 to reduce the body/ring of drums for a tighter feel.
  4. For sub weight on kicks, carefully add WEIGHT in the positive direction on a separate instance.

3. Mix Bus: Gentle Tonal Shaping

  1. Set CHARACTER to 0.15-0.25 with BIAS at center for a subtle blend of tape and tube warmth.
  2. Use TONE at -0.1 to -0.2 for gentle high-frequency softening.
  3. Set DRY/WET to 60-70% for parallel processing that retains natural dynamics.
  4. Enable Auto Gain for accurate A/B comparisons.

4. Acoustic Guitar: Warmth and Body

  1. Set FOCUS to -0.3 to fill out the lower midrange body.
  2. Add a Balance EQ layer with a gentle low-shelf boost at 200 Hz for warmth.
  3. Set CHARACTER to 0.2 with BIAS toward Tape (-0.4) for analog warmth.
  4. If the pick attack is too sharp, use ADSR Attack at -0.2 to soften transients.

5. Mastering: Broad Tonal Correction

  1. Use a Balance EQ layer for broad tonal corrections (gentle low shelf, gentle high shelf).
  2. Set FOCUS slightly positive (+0.1 to +0.2) if the mix needs more clarity.
  3. Set CHARACTER at 0.1 or lower for very subtle harmonic enhancement.
  4. Use DRY/WET at 80-90% to keep the processing transparent.
  5. Always enable Auto Gain when comparing processed vs. bypassed.

System Requirements

Plugin format AU (Audio Unit) + VST3
Platform macOS 11.0 (Big Sur) or later
Architecture Universal Binary (Intel + Apple Silicon native)
Internal precision 64-bit floating point
Latency Zero latency (no lookahead buffer)
RAM Minimum 4 GB
License One-time online activation, up to 3 machines
Tested DAWs Logic Pro, Ableton Live, Reaper, Cubase, Studio One, Nuendo, and all AU/VST3-compatible hosts

Troubleshooting

Plugin does not appear in my DAW

  • Make sure you have installed the correct format for your DAW (AU for Logic Pro, VST3 for most others).
  • Run a plugin rescan in your DAW's preferences. In Logic Pro, this happens automatically. In Ableton Live, go to Preferences > Plug-ins and click Rescan.
  • Verify the plugin files are in the correct locations: ~/Library/Audio/Plug-Ins/Components/ for AU, ~/Library/Audio/Plug-Ins/VST3/ for VST3.

License activation fails

  • Ensure you have an active internet connection for the one-time activation.
  • Check that you have not exceeded your 3-machine activation limit. You can deactivate a machine from the plugin's license panel.
  • If problems persist, contact hello@buchertaudio.com with your license key and we will resolve it promptly.

High CPU usage

  • Disable oversampling (set to 1x) if you do not need it. The 4x oversampling mode uses significantly more CPU.
  • Remove unused EQ layers from the layer stack.
  • The ADSR section uses additional internal analysis. If CPU is a concern, leave ADSR parameters at their default/neutral positions when not needed.

Clicks or pops when adjusting controls

  • Tonality EQ uses fixed-filter architecture with per-sample parameter smoothing. Clicks should not occur under normal use.
  • If you hear clicks, check whether they originate from another plugin in the chain or from buffer size issues in your DAW.
  • Try increasing your audio buffer size to 256 or 512 samples.

Need more help? Contact us at hello@buchertaudio.com