Sound Reaktor Pro Documentation

What is Sound Reaktor Pro?

Sound Reaktor Pro is an audio-reactive animation toolset for Blender. It analyzes an audio file and turns that analysis into animation, driving properties of your scene in time with the sound. Under the hood it uses proper signal-processing (NumPy and SciPy) to offer several analysis methods, from continuous frequency tracking to beat/onset detection, loudness, and other spectral measures, so you can react to whatever aspect of the sound matters for your shot.

More than a single-purpose effect, Sound Reaktor Pro is a universal bridge from audio to any numeric property Blender can express. The classic targets (Location, Rotation, Scale) are just the starting point. Through its Custom Property target you can route any analysis into shader values, Geometry Nodes inputs, light energy, camera settings, modifier parameters, constraint influences, shape keys, and more.

Sound Reaktor Pro does not lock you into a fixed workflow. It gives you a set of building blocks, several analysis methods, a range of animation targets, and two animation modes (keyframes and real-time drivers), and lets you combine them freely. Because these pieces are composable rather than a single fixed pipeline, users routinely build setups that were never explicitly designed in advance. That flexibility is the point: the tool provides the parts, and you decide how they connect.

In practice, a single analysis pass can make a material's emission pulse to a kick drum, a displacement modifier react to the bass, or a depth-of-field blur breathe with a vocal line, all from the same audio, all in sync.

Requirements

Sound Reaktor Pro is officially supported on official Blender releases only, currently (v2.6) from Blender 4.2 up to Blender 5.2. These are the versions Sound Reaktor Pro is tested against.

Sound Reaktor Pro is not officially supported on any unofficial Blender fork, because as a solo developers it is not realistic to test against every variant in existence. This includes, but is not limited to, forks such as Bforartists, K-Cycles, E-Cycles or Goo Engine.

Being unsupported does not necessarily mean it will not work. Many forks only add features on top of a standard Blender base and leave the rest of the application untouched. For example, K-Cycles adds render optimizations to Cycles, so Sound Reaktor Pro should work on it just fine. However, this cannot be guaranteed, since these forks cannot be tested. Use at your own risk.

Sound Reaktor Pro does NOT work with the standalone Octane Blender 4.3.1 for macOS. This is most likely caused by an incompatibility with the libraries bundled by Otoy, although it has not been possible to investigate this in depth. Note that Otoy has since moved away from shipping Octane as a standalone Blender build: modern Octane is an add-on that installs on top of an official Blender release and communicates with the separate Octane render server. If you need Sound Reaktor Pro alongside Octane, use a modern Octane version that runs as an add-on on official Blender instead of the old standalone build.

Installation

Installing the Add-on

The installation process is the same across all operating systems:

WARNING! Disabling and re-enabling in the same session.  On Windows, disabling Sound Reaktor and re-enabling it without restarting Blender first may cause dependency errors (missing SciPy, PyAV unable to load audio files). This is a known limitation of Blender's extension system on Windows. When an extension with binary dependencies is disabled, Blender attempts to unload those files while they are still locked in memory, which can leave the installation in an inconsistent state. If this happens, the fix is straightforward: disable the addon, restart Blender, then re-enable it. Do not re-enable it in the same session after disabling.

Sound Reaktor Pro relies on NumPy and SciPy for its audio analysis capabilities. NumPy handles the numerical computations, while SciPy provides the signal processing algorithms (FFT and onset detection) that make frequency analysis possible.To be able to open MP3, OGG, OPUS, FLAC, M4A, and AAC audio files, it uses the PyAV library. This is the reason why there is a version for each operating system and why the ZIP files are so large. Each of them includes those external libraries (SciPy and PyAV) compiled for each system. To ensure compatibility with Blender 5.1+, there is a specific version of the libraries for the newest Blender release(s).

Quick Start

This guide will get your first animation running in under a minute. We'll make a cube pulse to a kick drum:

Your cube should now be scaling up and down in sync with the kick drum. The animation keyframes have been automatically generated across the entire audio duration.

Interface Reference

The Sound Reaktor Pro panel is located in the 3D Viewport sidebar (press N) under the "Sound Reaktor Pro" tab. This section explains each control in detail.

Advanced/Easy Mode

Sound Reaktor Pro offers two interface layouts, controlled by a single Easy Mode preference found in Edit › Preferences › Add-ons › Sound Reaktor Pro.

• Advanced layout (default, Easy Mode off): every panel is visible, including Pre-filter, Analysis Preview and Advanced Settings. This is the full interface.
• Easy Mode (on): the three advanced panels above are hidden, leaving a simpler layout with only the essential controls. Good for a cleaner workspace or when you do not need the extra options.

This preference only changes what is shown. It does not change how the analysis works in any way. A project analyzed in Easy Mode and the same project analyzed in Advanced Mode produce identical results. Any advanced setting you configured stays in effect even after you switch to Easy Mode; it is simply hidden from view, not reset.

Audio File Settings

Audio File

Select the audio file to analyze. Sound Reaktor Pro supports WAV, MP3, OGG, FLAC, OPUS, M4A, and AAC files.

Note: The optimal format for working with Sound Reaktor is WAV. While the other supported formats will work perfectly, it's important to keep in mind that some of them, such as MP3, are lossy compressed formats. The human ear may not notice a difference, but the data that Sound Reaktor Pro uses for its processing will be degraded by this compression. In addition, decoding these audio formats adds some extra time to the analysis process.

Add to Sequencer

When enabled, Sound Reaktor Pro automatically adds your audio file to Blender's Video Sequencer, allowing you to hear the audio during playback. The audio strip is named with an "SR_" prefix for identification.

Replace Existing Audio

When enabled (recommended), removes any previous audio strips added by Sound Reaktor Pro (identified by "SR_" prefix) before adding the new one. Keeps your sequencer clean when experimenting with different audio files.

Keyframe Mode

The default mode of Sound Reaktor Pro is "Keyframe mode". In this mode, the addon analyzes the audio using the selected parameters and then creates keyframes on every frame throughout the animation, setting the timeline length according to the duration of the loaded audio file in the process. This mode is ideal for distributing the .blend file with the generated animations to users who do not have the addon, or for rendering on a render farm. The process is slower than in "Drivers" mode, which will be discussed next, although with update 2.4.2, keyframe creation is between 50 and 100 times faster than in previous versions.

The big button executes the entire Sound Reaktor Pro pipeline. When clicked, the add-on:

Important: You don't need to clear anything before re-running. Sound Reaktor Pro automatically replaces existing keyframes, so you can experiment freely by adjusting parameters and clicking again.

Driver Mode

By default, Sound Reaktor Pro bakes animation as keyframes, one keyframe per frame, permanently stored in the .blend file. Driver Mode is an alternative workflow: instead of generating keyframes, Sound Reaktor Pro analyzes the audio into memory and applies Blender drivers that read that data in real time during playback.

The toggle between the two modes is located in the main panel, just below the audio file selector:

Switching to Drivers changes the main button label from MAKE IT DANCE! to ANALYZE & DRIVE.

When to use Driver Mode

Use Keyframes when…	Use Drivers when…
You want the animation to work without Sound Reaktor Pro installed	You want to tweak parameters and re-analyze without rebaking
You're delivering the .blend to someone else	You're using Spectral Bins (requires Drivers)
You need accumulative rotation	You want lighter .blend files (no stored keyframes)
You're rendering on a farm with no addon access	You want to combine multiple analyses in one GN graph

Workflow

1. Select an object and configure your analysis settings as usual.
2. Switch the toggle to Drivers.
3. Click ANALYZE & DRIVE. Sound Reaktor Pro analyzes the audio and stores the result in RAM. Drivers are applied to the target property immediately.
4. Press Space to play the animation. The object responds to the audio in real time.

If you want the analysis to persist after closing Blender, enable Bake to Disk (see below) before clicking ANALYZE & DRIVE.

Bake to Disk

Analysis data loaded into RAM is lost when Blender closes. Enable Bake to Disk to save the analysis to a .npz cache file on disk. The cache is stored in a subfolder next to your .blend file:

my_project/
├── my_scene.blend
└── blendcache_my_scene/
    └── SR_cache_[hash].npz

When you reopen the .blend, Sound Reaktor Pro automatically reloads the cache. Drivers work immediately without re-analyzing.

Important: Bake to Disk requires the .blend file to be saved. If the file has not been saved yet, the option is disabled.

If analysis parameters change (audio file, frequency range, method, etc.), the existing cache is invalidated automatically and a new one is written on the next ANALYZE & DRIVE.

Driver Count Indicator

The panel displays the number of active Sound Reaktor Pro drivers on the selected object. This is useful when combining multiple analyses on the same object.

Bake to Keyframes

Once drivers are applied, you can convert them to standard keyframes at any time using the Bake to Keyframes button. This processes all Sound Reaktor Pro drivers on the active object at once and removes them after baking, leaving behind a regular keyframe animation that works without the addon.

Use this when:

• Sharing the file with collaborators who don't have Sound Reaktor Pro installed.
• Sending to a render farm.
• You're done tweaking and want to finalize the animation.

Although since version 2.4.2 of Sound Reaktor Pro the creation of keyframes in Keyframe Mode is much faster than in previous versions, unfortunately and due to limitations of the Blender API, the conversion of drivers to keyframes is a relative slow process. This is especially noticeable when there is a significant number of drivers on the object where those drivers need to be converted into keyframes. 

Remove Drivers

The Remove Drivers button removes all Sound Reaktor Pro drivers from the active object without converting them to keyframes. The analysis data in RAM (and on disk, if Bake to Disk was enabled) is preserved. You can re-apply drivers at any time with ANALYZE & DRIVE.

Limitations

• Accumulative Rotation is not supported in Driver Mode. The option is grayed out when Drivers is active. Use Keyframes mode if you need accumulative rotation.
• Analysis data stored in RAM only (Bake to Disk disabled) is lost when Blender closes. If you reopen the file without the cache, drivers will be present but inactive, re-run ANALYZE & DRIVE to restore them.

• Only one driver-based analysis can be active at a time because the analysis data lives in a single shared store. The recommended workflow for animating multiple objects with different analyses is sequential. Configure and apply drivers to the first object, tweak until the result is right, then use Bake to Keyframes to convert the drivers to permanent keyframes. Once baked, that object's animation is independent of the driver store and the next object can be analyzed without affecting it. Repeat for each object.

  The one exception is Spectral Bins: its 9-band data is stored separately from single-channel analyses, so a Spectral Bins node group and a single-channel driver (FFT, Onset, RMS, etc.) can coexist on different objects simultaneously without interfering with each other.

Presets

A preset is a saved snapshot of your current Sound Reaktor Pro settings. Once you find a combination of analysis method, frequency range, sensitivity, smoothing, FFT size and all the rest that works for a given track, you can store it and bring it back later with a single click. This is handy when you are experimenting: you never lose your "sweet spot" just because you kept tweaking parameters afterwards.

Presets do not save the KEYFRAMES / DRIVERS mode. This is intentional and entirely depends on the user which of the two modes they want to apply the settings saved in their presets.

Presets are stored inside the .blend file, so they travel with your project.

Saving a Preset

Click the + button next to the preset list. A small dialog asks for a name (a default like "Preset 1" is suggested, edit it freely) and confirms. The new preset captures the current state of every relevant setting, including the audio file path.

The audio path is stored both as an absolute path and as a path relative to the .blend, when the file has been saved. When you later apply the preset, Sound Reaktor Pro tries the relative path first and falls back to the absolute one. This means a preset keeps working even if you move the whole project folder somewhere else, as long as the audio file stays in the same place relative to the .blend.

Applying a preset

Select a preset in the list and click Apply Preset. All stored settings are restored at once. Note that applying a preset only restores settings; it does not run the analysis. Press MAKE IT DANCE! (or ANALYZE & DRIVE) afterwards as usual.

Applying a Custom-target preset to a different object. If a preset uses a Custom Property target, that target was set up on a specific object when the preset was saved. If you apply the preset while a different object is active, a centered dialog warns you, because pressing MAKE IT DANCE! would animate the original object the target points at, not the one you have selected now. The warning tells you which object the preset belongs to, so you can re-select the target on the active object if that is what you intended. Location, Rotation and Scale presets are not affected by this, as they always apply to whatever object is active.

Deleting a preset

Select a preset and click the - button next to the list to remove it.

Analysis Preview

The Analysis Preview panel shows a quick statistical summary of the last baked analysis. It shows Floor (minimum), Peak (maximum), Average, and P95 (95th percentile) values across all frames. Use it to understand the dynamic range of your audio signal before animating.

The cost of Analysis Preview is zero. Sound Reaktor Pro analyzes the audio to display the values, so when MAKE IT DANCE! is pressed, it will use the cached values from the audio analysis preview.

Pre-Filter

Before the audio reaches the analyzer, you can run it through a high-pass, a low-pass filter or both.

This is useful when your frequency range selection alone isn't enough to isolate what you're after: a high-pass removes low-end rumble that might skew the analysis upward, while a low-pass cuts the high-frequency content that can introduce noise into bass-focused animations. 

Would you like to know more? https://www.mixinglessons.com/pass-filter/

Frequency Range

The frequency range determines which part of the audio spectrum Sound Reaktor Pro listens to. Different instruments and sounds occupy different frequency ranges.

Preset Mode

Nine carefully tuned frequency ranges covering the most common use cases:

Custom Mode

For precise control, specify any range between 20 Hz and 20,000 Hz. Some useful custom ranges:

Analysis Settings

Controls how Sound Reaktor Pro interprets your audio. Sound Reaktor Pro 2.0+ features six analysis methods: FFT, Onset, RMS, Centroid, Flatness or Rolloff Frequency.

Choosing Your Analysis Method

FFT (Fast Fourier Transform) analyzes continuous energy in your selected frequency range. It measures "how loud is this frequency band right now?" at every frame, producing smooth, flowing animations that follow audio energy.

Onset Detection looks for sudden changes in the audio: the attack of a drum hit, the pluck of a string, the start of a vocal phrase. It identifies discrete moments where something "happens" creating snappy, rhythmic animation that reacts precisely when beats occur.

RMS Energy (Root Mean Square) measures the overall loudness of the audio at every frame. It's not focused on a specific frequency range, but the total volume of the signal. Think of it as a "master volume meter" for your animation. It's the simplest and most intuitive of all methods: loud = high value, quiet = low value. Great starting point if FFT feels too complex.

Spectral Centroid tracks where the "brightness" of the sound is at any given moment. A low value means the audio is bass-heavy (rumbles, low drones), a high value means it's treble-heavy (cymbals, high-pitched synths). It's particularly effective for animating color, light intensity, or any property where you want the animation to reflect the tonal character of the music rather than just its loudness. Spectral Centroid is slightly more advanced than RMS, FFT or Onset. Results depend heavily on your frequency range settings.

Spectral Flatness distinguishes between tonal sounds (musical notes, sustained synths) and noise-like sounds (cymbals, distortion, white noise). Values close to 0 mean the audio is pitched and harmonic and values close to 1 mean it's noisy and unpitched. Useful for triggering effects that should behave differently during melodic sections versus percussive or noisy ones. For example, a material property that changes character when a distorted guitar kicks in. Flatness is an advanced method and requires some experimentation to get useful results.

Spectral Rolloff tracks how much of the audio's energy is concentrated in the lower frequencies versus spreading into the higher ones. A low value means most energy is in the bass and a high value means energy has spread across the full spectrum. It's a good indicator of the overall harmonic richness of a sound at any moment. Like Flatness, Rolloff is and advanced method. It works best for subtle, slowly-evolving animations that follow the tonal complexity of the audio rather than its rhythm or loudness.

FFT Parameters

Sensitivity

Controls how the animation responds to different volume levels. It applies dynamic compression to amplitude values:

Smoothing

Reduces rapid fluctuations by averaging each frame's value with previous frames:

Noise Filter

Eliminates tiny fluctuations below a threshold, preventing jitter during quiet passages:

Normalization

See the next section.

Onset Parameters

Sensitivity

Controls how easily a beat is detected:

Attack Strength

Determines how much the animation moves when a beat is detected:

Decay Time

Controls how quickly animation returns to rest after a beat (in seconds):

Min Time Between

Minimum interval between detected onsets, preventing duplicate triggers:

RMS Parameters

Sensitivity

Controls how the animation responds to different volume levels. It applies dynamic compression to amplitude values:

Attack / Release

In Sound Reaktor Pro 2.5, the RMS method replaces the generic Smoothing slider with two controls, Attack and Release, that together form an envelope follower. Instead of smoothing the signal equally in both directions, you can now control the rise and the fall separately:

• Attack controls how fast the value rises to follow a hit. 0 snaps up instantly and higher values ease into the peak more gradually.
• Release controls how fast the value falls after a hit. 0 drops instantly and higher values give a slower, smoother decay.

This produces the classic "breathing" or sidechain feel: the animation jumps up sharply on a beat and then eases back down. A fast Attack with a slow Release is the typical starting point.

Attack and Release are simply a more expressive version of Smoothing. Setting both to the same value reproduces the old symmetric Smoothing behavior exactly, so nothing is lost. The other analysis methods (FFT, Onset, Centroid, Flatness, Rolloff) keep using the regular Smoothing control. Only RMS uses Attack/Release.

Noise Filter

Eliminates tiny fluctuations below a threshold, preventing jitter during quiet passages:

Normalization

See the next section.

Centroid Parameters

Sensitivity

Controls how strongly the animation reacts to shifts in tonal brightness. Since centroid values tend to change gradually, higher sensitivity can help make subtle shifts more visible:

Smoothing

Centroid values naturally evolve slowly. Smoothing reinforces this behavior:

Noise Filter

Prevents the centroid from jumping erratically during near-silent frames, where the calculated center of mass becomes unreliable:

Flatness Parameters

Sensitivity

Controls how strongly the animation reacts to changes between tonal and noisy content. Since flatness values often cluster toward the lower end for musical audio, higher sensitivity can help bring out more variation:

Smoothing

Flatness can change abruptly when audio transitions between pitched and noisy content. Smoothing controls how sharply those transitions appear in the animation:

Noise Filter

Prevents near-zero flatness values during silent frames from causing unwanted baseline animation:

Rolloff Parameters

Rolloff Threshold

Sets the percentage of total spectral energy used to calculate the rolloff frequency. This is the primary parameter for tuning the method's behavior:

Sensitivity

Controls how strongly the animation reacts to changes in harmonic spread. Rolloff values tend to evolve slowly, so higher sensitivity can help surface gradual shifts:

Smoothing

Rolloff values naturally evolve slowly. Additional smoothing reinforces this but can reduce responsiveness to faster harmonic changes:

Noise Filter

Prevents erratic rolloff values during near-silent frames where the energy distribution becomes unreliable:

Advanced Settings

The Advanced Settings panel exposes two controls that govern how the frequency analysis is performed: FFT Size and Window Function. Both are optional. The defaults (FFT Size 2048, Window Hann) match previous versions of Sound Reaktor Pro, so if you never open this panel, nothing changes.

These two settings only affect the frequency-based analysis methods (FFT, Onset, Spectral Centroid, Flatness, Rolloff and Spectral Bins). The RMS method works directly on the raw waveform and does not use them, so the FFT Size and Window controls are hidden while RMS is selected.

FFT Size

To analyze audio, Sound Reaktor Pro slices the sound into short overlapping chunks and measures the frequencies present in each one. FFT Size is the length of that chunk, measured in samples. It sets the trade-off between two kinds of detail that pull in opposite directions:

• Larger sizes (e.g. 8192, 16384) look at a longer stretch of audio at once, so they can tell frequencies apart very precisely. The result is smoother and more accurate in pitch, but slower to react. Fast changes get averaged out. This is the "good frequency detail, coarse timing" end.
• Smaller sizes (e.g. 128, 256) look at a very short stretch, so they react instantly to sudden events like drum hits, at the cost of blurring nearby frequencies together. This is the "sharp timing, coarse frequency detail" end.

Think of it as a zoom control between when something happens and what pitch it is. The available values range from 128 to 32768 (each step doubles the previous one), with 2048 as the balanced default that works well for most material.

A practical rule of thumb: for punchy, rhythmic animation (kicks, percussion, tight transients) try a smaller FFT Size. For smooth, flowing animation driven by sustained tones (pads, bass, melodic content) try a larger one. There is no wrong answer. Change it, click MAKE IT DANCE! again, and compare.

Regardless of the FFT Size you choose, Sound Reaktor Pro always analyzes the entire clip. Small window sizes no longer skip over parts of the audio, a problem that existed in earlier versions.

Is a large FFT Size the same as Smoothing? Not quite, even though both make the final curve look smoother. The difference is when they act. A large FFT Size smooths during analysis: by looking at a longer stretch of audio at once, it averages the sound before the animation data is ever produced, so fine, fast detail is never captured in the first place. Smoothing acts after analysis, blending together values that were already measured frame by frame. The practical consequence: a sharp transient that a large FFT Size averages away is gone for good, whereas a small FFT Size followed by Smoothing keeps the event (it was detected) while still rounding off its shape. Use FFT Size to set the character of the analysis (punchy vs. flowing) and Smoothing to polish jitter out of the final curve. They can produce similar-looking results, but reaching for a large FFT Size purely to smooth is usually the wrong tool.

Window Function

Because each chunk is a short slice cut out of a continuous sound, its edges end abruptly. Those hard edges introduce a bit of false frequency content into the measurement, an artifact known as spectral leakage. A window function smooths the volume of each chunk down to zero at its edges before analysis, which greatly reduces that artifact.

For everyday use you do not need to change this. The four options are:

• Hann (default): a well-balanced, general-purpose window. The right choice in almost every case.
• Hamming: very similar to Hann, with slightly different behavior at the edges of each frequency band. Differences are usually subtle.
• Blackman: suppresses leakage more aggressively, giving cleaner separation between strong frequencies, at the cost of slightly wider, less precise peaks.
• Rectangular: applies no smoothing at all. Maximum precision on steady tones, but the most leakage on anything that changes. Mainly useful for experimentation or very stable signals.

In practice Hann covers the vast majority of situations. The others are there for fine tuning when you want to push a particular character out of the analysis.

In the interface, the Advanced Settings panel header shows a small modifier icon whenever FFT Size or Window (or the channel selector, covered next) is set to something other than its default, so you can tell at a glance that non-default settings are active without expanding the panel.

Audio Channel Selection

By default, Sound Reaktor Pro mixes every channel of a stereo or multichannel file down into a single mono signal before analysis. That is the right choice most of the time and is controlled by the Mix All Channels option, which is on by default.

The channel controls only appear when the loaded file actually has more than one channel. For mono files there is nothing to choose, so the option stays hidden and out of your way.

When you turn Mix All Channels off, a Channel field appears where you enter the 0-based index of the single channel you want to analyze (0 for the first channel, 1 for the second, and so on). On a standard stereo file, 0 is the left channel and 1 is the right channel. If you enter an index the file does not have, a red warning tells you the highest valid channel number.

Analyzing a single channel is useful when:

• Content is panned to one side (for example a lead instrument sitting mostly in the right channel) and you want to react to it without the other side diluting the signal.
• You have a track with different content on each channel and want each to drive a different object.
• You need to recover out-of-phase content that mixing to mono would partially or completely cancel out.

Reopening a project. The channel count of a file is not stored in the .blend directly. When you reopen a saved project, Sound Reaktor Pro recovers it automatically by reading the audio strip it previously added to the Video Sequencer (the one prefixed with SR_). This means the channel selector reappears on its own for multichannel files, so you do not have to re-pick the audio file just to get the channel options back.

Normalization

Sound Reaktor Pro produces amplitude values in the range 0.0–1.0. Normalization controls how raw audio energy is mapped to that range. Two modes are available when using FFT, RMS, or Spectral Bins analysis.

Per-Band Peak (default)

The loudest moment in the analysis is set to 1.0. Every other frame is scaled relative to that peak.

A track where the kick barely reaches half the energy of the chorus will have its kick mapped to ~0.5 .The full 0–1 range is used only if the target frequency band actually gets loud at some point.

Good for:

• Single-property animation (Location, Rotation, Scale, Custom Property).
• Getting the maximum animation range out of quiet or narrow frequency bands.
• Situations where you want the object to hit its full Range value at least once during the track.

Watch out for:

When using Spectral Bins, each band is normalized independently. A quiet high-frequency band will still reach 1.0 . It will animate with the same range as a loud low-frequency band even if the actual energy difference between them is large. This flattens the natural loudness relationships between bands.

Global

All frequency bands share a single reference scale, the 99th percentile of the full spectrogram. Bands that are naturally louder reach values closer to 1.0, bands that are naturally quieter stay lower.

This means the relative energy differences between bands are preserved. If the bass is three times louder than the highs in the audio, the bass output will be roughly three times higher in the animation data as well.

The 99th percentile is used instead of the absolute peak to avoid a single transient spike dominating the scale and compressing everything else.

Good for:

• Spectral Bins: preserves the natural loudness hierarchy across the 9 frequency bands. The animation "feels" like the audio bass moves more than highs when the bass is louder.
• Scenes where the relative difference between multiple simultaneous analyses is meaningful.
• Tracks with a consistent loudness profile throughout.

Watch out for:

• Quiet or sparse frequency bands may produce very little animation movement. They stay low because they are genuinely quiet relative to the rest of the track. Increase Sensitivity or Range to compensate.
• Tracks with a very loud intro followed by a quiet body (or vice versa) may produce unexpected scaling, since the global reference is computed across the full track.

Choosing Between the Two

	Per-Band Peak	Global
Each band fills 0–1 range	Yes	Only the loudest band
Relative energy between bands preserved	No	Yes
Best for single-property animation	Yes	No
Best for Spectral Bins	No	Yes
Quiet bands still animate visibly	Yes	Not without Sensitivity boost

Animate Property

Determines which property of your object responds to the audio: Location, Rotation, Scale, Custom Property or Spectral Bins.

Location

Moves your object through 3D space in response to audio.

The Bipolar option (available for Location and Rotation) has been rebuilt in 2.5. Bipolar animation now centers correctly on the rest value and swings symmetrically with the dynamics of the audio, instead of the flawed behavior of earlier versions.

Rotation

Spins your object based on audio amplitude.

Scale

Makes your object grow and shrink with audio. The classic "pulsing" effect.

Custom Property

Custom mode is the most powerful and versatile animation target in Sound Reaktor Pro because it breaks the boundary between audio-reactive animation and the rest of Blender.

 While Location, Rotation, and Scale are limited to object transforms, Custom mode lets you drive any numeric property in the entire application: shader node values, geometry node parameters, light energy, camera focal length, modifier inputs, constraint influences, shape key weights, compositor node values, and more.

 This means Sound Reaktor Pro is not just an object animation tool: it is a universal audio-to-parameter bridge for anything Blender can express as a number. A single analysis pass can make a material's emission strength pulse to the kick drum, a displacement modifier react to the bass, or a depth-of-field blur open and close with the vocal track, properties that have no equivalent in transform-based animation modes.

 Custom mode is the entry point for routing any of Sound Reaktor's six analysis methods into a Geometry Nodes or Shader graph, making it the foundation on which the most sophisticated audio-reactive setups are built.

Getting the Data Path

Although the method below of manually copying and pasting the datapath is valid, starting from version 2.2.0 there is a faster and more direct way to do it. Simply choose the ‘Send to Sound Reaktor’ option in the context menu of the property you want to animate, and the addon will handle the entire process automatically.

The add-on validates your path immediately. A checkmark means the path works.

Supported Property Types

Works: Light energy, shader node values (emission, roughness), modifier parameters, Geometry Nodes, camera settings, constraint influences, shape key values, Compositor Nodes.

Does not work: Integer properties(*), boolean properties (checkboxes), enum properties (dropdowns), string properties (text fields).

Value Range Controls

Base value is the lowest point in the animation and Base Value + Range is the highest point.

Although Sound Reaktor Pro does not directly support integer parameters, there are cases where they can still be used with the help of Geometry Nodes. In the following video, a method is shown for animating the subdivision level, which is an integer parameter, of an object using Sound Reaktor Pro.

Spectral Bins

Spectral Bins splits the audio frequency spectrum into 9 independent bands and animates all of them simultaneously in a single analysis pass. Instead of generating keyframes, it works exclusively in Driver Mode . The analysis data is stored in RAM (and optionally cached to disk as a .npz file alongside your .blend).

On first use, Sound Reaktor Pro automatically generates two node groups: SR Spectral Bins (Geometry Nodes) and SR Spectral Bins Shader (Shader nodes). Each group exposes 9 float outputs, one per frequency band, ranging from 0.0 to 1.0. You can plug these outputs into any property in a GN modifier or material, displacement amount, scale, emission strength, roughness, or anything else that accepts a float. The node groups are shared across all objects in the scene, so adding the same group to multiple objects costs nothing extra, they all read from the same in-memory data store.

 Normalization follows the same dropdown as FFT mode: Per-Band Peak (default) normalizes each band independently to its own peak amplitude. Global uses a single 99th-percentile divisor across the full spectrogram, preserving relative energy differences between bands so that a quiet high-frequency band stays quieter than a loud bass band.

Limitations: Spectral Bins requires the .blend file to be saved if disk cache is enabled. Unsaved files keep the data in RAM only, which is lost when Blender closes. The node groups are generated once and reused; if you delete them manually, use the Regenerate Node Groups button to rebuild them.

One of the most powerful aspects of Spectral Bins is that you can combine it with other Sound Reaktor Pro analyses in the same Geometry Nodes or Shader graph. The SR Spectral Bins node group gives you 9 outputs (one per frequency band). On top of those, you can freely add more analyses, and there is no fixed limit on how many properties you drive. What matters is how many independent analyses you can feed in at once, which differs between keyframes and drivers:

• With Keyframes there is no limit on independent analyses. Each analysis you bake to keyframes is frozen into its own property as independent data, so you can bake one to a kick, another to the bass, another to the vocals, and route them all into the same graph. Ten, twenty, a hundred, whatever your setup needs, each keeps its own values.
• With Drivers, all SR_amp drivers share a single live analysis. You can add as many driver-based outputs as you want, but they all read the same analysis (the most recent ANALYZE & DRIVE), so they all follow the same curve. The 9 Spectral Bins bands are the exception: SR_bin exposes 9 distinct band sources at once. See the note on driver behavior below for the full picture.

So a practical way to combine everything: use Spectral Bins for your 9 frequency bands, use Drivers for one live analysis you want to scrub in real time, and use Keyframes for any additional independent analyses (kick, bass, vocals...), all feeding the same Geometry Nodes or Shader setup.

New! Since version 2.6, it is possible to convert spectral bins node groups to keyframes using the "Bake Bins to Keyframes" button.

SR Animation Info Panel

This collapsible panel appears below the main panel when you select an object that has been animated with Sound Reaktor Pro. It provides a summary of all animations applied to that object, including:

Up to now, the Animation Info panel was a beta feature whose role was purely informational: it gave you an at-a-glance summary of the animations applied to an object. In Sound Reaktor Pro v2.5 it grows into a mature part of the workflow. It still shows that summary, now with more accurate information. Custom-property animations now show a readable name in the Animation Info panel. For example, a node socket appears as "Principled BSDF: Roughness" instead of a cryptic "default_value", matching the name you see in the Graph Editor.).

 It gains a real editing function: you can delete animations and their metadata directly from the panel, without hunting them down by hand and without leaving orphaned metadata behind.

Each animation entry listed in the Animation Info panel now has a trash icon at its right edge. Clicking it removes that animation completely: both its keyframes (the entire F-curve, not just the visible keys) and its entry in the Animation Info panel, in a single click.

The deletion is fully undoable with Ctrl+Z, so there is no confirmation prompt. If you remove the wrong animation, just undo. This works for every target type, including custom properties on shader nodes, Geometry Nodes and modifiers.

Sound Reaktor Pro 2.0+ stores a complete snapshot of every bake parameter alongside each animated property, far more than what the Animation Info panel displays. Fields such as smoothing factor, noise filter settings, high-pass and low-pass filter configuration, onset envelope parameters (attack, decay, minimum time), rolloff threshold percentage, per-axis base values, frame start, frames-per-second, bake timestamp, and both absolute and relative audio file paths are all recorded silently in the background. 

Viewing Analysis Progress

For longer audio files, you may want to monitor progress. Open Blender's System Console before clicking "MAKE IT DANCE!":

The console displays detailed progress information including frames processed, frequency bands analyzed, and any warnings or errors.

Roadmap

Sound Reaktor Pro is actively developed with new features planned for future releases.

Near Term

Medium Term

Have an idea? Feature requests are welcome through SuperHive Market's messaging system or via support email.

Changelog

Version 2.6 (Updated: 2026/07/23)

• Add: Blender 5.2 LTS compatibility.
• Add: Bake the SR_bin drivers on the shared "SR Spectral Bins" node groups (GN+ Shader) to keyframes.

Version 2.5 (Updated: 2026/07/10)

• Add: Configurable FFT size and window function. New Advanced Settings let you choose the analysis window size (128–32768) and the window type (Hann, Hamming, Blackman, Rectangular). 

• Add: Audio channel selection. For stereo and multichannel files you can now analyze all channels mixed together, or pick a single channel (Left, Right, or any other).

• Add: Automatic channel recovery when reopening a project. 

• Add: Delete button in Animation Info. Each animation entry now has a trash icon that removes both the animation (its keyframes) and its info entry in one click.

• Add: Clearer names for custom-property animations. 

• Add: Presets. Save your current settings as a named preset and restore them later with one click, so your "sweet spot" is never lost when you tweak parameters or swap the audio file.

• Add asymmetric envelope follower (Attack/Release) to RMS analysis, replacing the symmetric Smoothing slider in RMS mode.

• Add: Advanced Mode toggle (Easy / Advanced layout). A new preference lets you hide the advanced panels (Pre-filter, Analysis Preview, Advanced Settings) for a simpler Easy layout.

• Fix: Rework axis selection (Location/Rotation/Scale) and remove "All" toggle.
• Fix: reset Accumulative rotation when switching to Driver Mode, so its stale ON state no longer keeps Bipolar greyed out.

• Fix: Bipolar mode (Location and Rotation) rebuilt. Bipolar animation now centers correctly on the rest value and swings symmetrically with the audio's dynamics. Keyframe mode and Driver mode now produce identical results.

• Fix: Small FFT sizes no longer skip audio. With small analysis windows the engine could jump over parts of the sound, producing empty or garbled animation. The analysis now always covers the whole clip, whatever the window size.

• Fix: Applying a preset to the wrong object is now caught. If a preset's custom target was set up on one object and you apply it while a different object is active, a centered dialog warns you.

• Fix: RMS Attack/Release now invalidate the analysis cache.
• Fix: preset save crashed on BoolVectorProperty (axis vectors).

Version 2.4.2 (Updated: 2026/04/20)

• Add: Shader node group for Spectral Bins ("SR Spectral Bins Shader") . Use frequency data directly in materials. Both node groups are auto-generated on first use.
• Add: Drivers mode UX improvements. Main button shows "ANALYZE & DRIVE" with a dedicated icon, dynamic tooltip describes the active mode, SR driver count is shown in the panel, node groups regenerate in-place preserving existing references in the node editor.
• Fix: 50–200× faster keyframe baking! Scale, Location, Rotation and Custom Property now inject keyframes in bulk instead of one by one.
• Fix: Custom data path refactoring to use as a function with keyframe and driver mode.
• Fix: Custom driver not animating shape keys.
• Fix: Custom path parser: modifier names with brackets, shape key driver target, shared parser between keyframe bake and driver apply.
• Fix: Sound Reaktor Pro driver detection and removal missing shader node tree, material, and shape key animation datablocks.
• Fix: Extend Sound Reaktor Pro driver detection to object data, data node tree, lights and cameras animation datablocks.
• Fix: spectral centroid now respects the user-selected frequency band (previously computed over the full spectrum, ignoring Frequency Range).
• Fix: Driver frame offset no longer collapses frame_start=0 to 1 due to Python falsy semantics.
• Fix: Analyze_fft_bins replaces its O(bins × frames × columns) nested loop with a precomputed frame→STFT-column mapping for a significant speedup on long tracks.
• Fix: Timeline frame bounds now use proper numeric limits instead of hardcoded values, preventing edge cases with very long audio files.
• Fix: Spectral Bins tooltip now correctly mentions both Geometry Nodes and Shader node groups.
• Fix: Old cache files on disk are now purged before writing a new one, preventing stale .npz files from accumulating.
• Fix: Accumulative rotation toggle is now grayed out in Drivers mode. Accumulative rotation is not supported with real-time drivers.
• Fix: Custom property driver mode now works for all target types.
• Fix: Custom path parser now correctly handles modifier names containing brackets.
• Fix: Shape key drivers now target the Key datablock instead of the individual KeyBlock.
• Fix: Sound Reaktor Pro driver detection and removal now searches all relevant datablocks.
• FFT and Spectral Bins drivers can now coexist on different objects using the same audio file.

Version 2.4.1

• Fix: Stereo-to-mono conversion in the WAV loader now correctly averages channels before casting, preventing integer overflow with 16-bit files.
• Fix: Butterworth pre-filter no longer crashes when the cutoff frequency is at or above the Nyquist limit.
• Fix: Warning shown in Frequency Range panel when the minimum frequency is set higher than the maximum.
• Fix: Driver engine NPZ file handle is now properly closed after reading, preventing file lock issues on Windows.

Version 2.4.0

• Add: Animate Property resets to Scale automatically when switching from Drivers to Keyframes mode, preventing invalid state.
• Add: Audio File label and file picker merged into a single compact row.
• Add: Normalization dropdown in Analysis Settings (FFT, RMS and Spectral Bins) with two modes: Per-Band Peak (default, legacy behavior) and Global (99th-percentile of the full spectrogram).
• Fix: Analysis Settings and Animate Property panels are now collapsed by default for a cleaner initial UI.
• Fix: Driver Mode UI refactored. Radio buttons for mode selection, inline cache info, SR Data sub-panel removed.
• Fix: FFT normalization no longer destroys inter-band amplitude differences.
• Fix: RMS normalization suffered from the same destructive min-max pattern and is now corrected, with the new dropdown available in RMS mode as well.
• Fix: Spectral Bins normalization pipeline corrected.
• Fix: STFT overlap is now matched to the project FPS, eliminating jitter artifacts at high frame rates (60fps+).

Version 2.3.0

• Add: Driver Mode. Analyze audio to RAM and apply real-time drivers to object properties. Drivers can be removed or converted to keyframes at any time.
• Add: Disk cache for Driver Mode. Save analysis data to .npz file alongside the .blend for persistent playback across sessions.
• Add: Spectral Bins. Animate 9 frequency bands simultaneously using a single analysis pass. Generates a Geometry Nodes group ("SR Spectral Bins") with one output per band.
• Add: Bake to Keyframes. Converts all Sound Reaktor Pro drivers on the active object to standard keyframes and removes the drivers.
• Add: Remove Drivers. Removes all SR drivers from the active object without baking.

Version 2.2.1 (Updated: 2026/03/26)

Version 2.0.1

Version 2.0.0

Version 1.9.3

Version 1.9.2

Version 1.9.1

Version 1.9.0

Version 1.8.3

Version 1.8.2

Version 1.8.1

Version 1.8

Version 1.7.1

Version 1.7

Version 1.6

Version 1.5

Version 1.3.1

Version 1.3

Version 1.2

Version 1.1.1

Version 1.1

Version 1.0 (First Private Beta)

Version 0.9

Version 0.8

Version 0.7

Version 0.6

Version 0.5

Version 0.4

Version 0.3

Version 0.2

Version 0.1 (Initial Alpha Release)

Credits

Sound Reaktor Pro was developed by Yatima.

Third-Party Libraries

Sound Reaktor Pro depends on the following open-source libraries:

NumPy

NumPy is the fundamental package for scientific computing in Python, providing support for large, multi-dimensional arrays and matrices, along with a collection of mathematical functions to operate on these arrays.

SciPy

SciPy is a library for scientific and technical computing, built on NumPy. Sound Reaktor Pro uses SciPy's signal processing module for FFT analysis and onset detection algorithms.

PyAV

PyAV provides Pythonic bindings for FFmpeg libraries, offering direct, high-level access to video and audio streams.

The BSD 3-Clause License permits redistribution and use in source and binary forms, with or without modification, provided that copyright notices and license terms are retained.

Contact and Support

If you encounter issues, have questions, or want to suggest features, there are two ways to reach support:

blenderartists.org Thread

To discuss Sound Reaktor Pro, follow updates, or get general support, there is also a thread on blenderartists.org forum.

Email

For technical support, bug reports, or feature requests:

support@yatima.xyz

When Reporting Bugs

Please include the following information to help diagnose issues quickly:

Tip: Detailed information helps provide effective solutions faster. The more context you provide, the better we can assist you!