Voxengo SPAN
voxengo.com
What it is
Voxengo SPAN is a free real-time FFT spectrum analyzer plugin for audio and music production applications. It analyzes stereo, mono, mid-side, and surround signals, including 5.1 and 7.1, and can display spectra from two channels or channel groups at once. Metering includes EBU R128 and K-system readings, RMS and true-peak measurements, clipping detection, and stereo correlation. Users can adjust FFT block size, window overlap, visual slope, smoothing, and a secondary spectrum display. Other functions include output power statistics, channel routing and grouping, presets, undo and redo, and A/B comparisons. SPAN is available for Windows and macOS in VST, VST3, and AAX formats, with AudioUnit also listed for Mac. The maker lists Windows XP and later and macOS 10.12 and later, with a 2.5 GHz dual-core or faster processor and at least 4 GB of RAM. Spectrum import and export for track comparisons is a SPAN Plus feature; the free plugin workaround works only in some hosts.
Spec sheet
- What it does
- SPAN is a real-time FFT frequency-spectrum analyzer plugin for professional music and audio production.Read 15 Oct 2026 · voxengo.com
- Purpose
- SPAN is a free real-time FFT audio frequency spectrum analyzer plugin for professional audio and music production applications.Read 3 Oct 2026 · voxengo.com
- Integrations
- Listed compatible hosts include Ableton Live, Cubase, Logic Pro, REAPER, Pro Tools, FL Studio, Studio One, OBS, Bitwig, Nuendo, WaveLab, GarageBand, and others.Read 15 Oct 2026 · voxengo.com
- Support
- Voxengo says customer support issues are handled as soon as possible and directs users to its product-specific Q&A before contacting staff.Read 3 Oct 2026 · voxengo.com
- License
- Voxengo software is copyrighted proprietary software governed by an accompanying end-user license; redistribution is prohibited unless that license permits it.Read 15 Oct 2026 · voxengo.com
- Founded
- The maker says Voxengo became a full-time commercial endeavor in December 2002.Read 15 Oct 2026 · voxengo.com
- Additional features
- The feature list includes spectrum smoothing, resizable interface, output signal power statistics, channel routing and grouping, preset management, undo/redo, and A/B comparisons.Read 3 Oct 2026 · voxengo.com
- Analysis modes
- It provides stereo, mono, mid-side, and surround spectrum analysis, including 5.1 and 7.1.Read 3 Oct 2026 · voxengo.com
- API and SDK
- The documentation describes SPAN as a plugin loaded by AudioUnit, AAX, VST, or VST3 hosts and does not specify a public API or SDK.Read 15 Oct 2026 · voxengo.com
- Authorization
- Free Voxengo plugins do not require a product key or online authorization.Read 15 Oct 2026 · voxengo.com
- Correlation meter
- SPAN includes stereo-correlation metering for checking phase and mono compatibility.Read 15 Oct 2026 · voxengo.com
- Current version
- The downloads index lists SPAN version 3.24 released April 4, 2026.Read 15 Oct 2026 · voxengo.com
- Documentation
- The product page links English, French, German, and Russian user guides, including a seven-page English PDF covering spectrum, statistics, metering, and correlation.Read 15 Oct 2026 · voxengo.com
- Downloads
- Separate Mac and Windows downloads are offered; the product page lists AU, AAX, and VST3 for Mac and VST, VST3, and AAX for Windows.Read 3 Oct 2026 · voxengo.com
- FFT configuration
- Users can set Fourier block size, FFT-window overlap, visual slope, secondary-spectrum type, and smoothing.Read 15 Oct 2026 · voxengo.com
- Formats
- Official downloads provide VST, VST3, AudioUnit, and AAX builds.Read 15 Oct 2026 · voxengo.com
- Host integrations
- Listed compatible hosts include Ableton Live, Cubase, Logic Pro, REAPER, Pro Tools, FL Studio, Studio One, OBS, Bitwig Studio, Nuendo, and Adobe Audition.Read 3 Oct 2026 · voxengo.com
- Installation model
- The primary guide says each platform and plugin specification is distributed in a separate archive or installer containing the binary, documents, license agreement, and change history.Read 15 Oct 2026 · voxengo.com
- Known limitation
- Voxengo says importing and exporting spectra for easy track comparisons is a SPAN Plus feature and that the free plugin method works only in some hosts such as Ableton Live.Read 3 Oct 2026 · voxengo.com
- Limit: learning curve and scope
- An independent 2026 review described the interface as utilitarian, warned that beginners can misread FFT and slope settings, and noted that SPAN analyzes problems rather than correcting them.Read 15 Oct 2026 · michaelmusco.com
- Limit: multi-channel setup
- Bonedo said the multi-channel function was not immediately intuitive.Read 15 Oct 2026 · bonedo.de
- Limit: no standalone operation
- Independent coverage describes SPAN as a plugin for Windows and macOS hosts rather than a standalone audio editor or mastering application.Read 15 Oct 2026 · audiopluginlist.com
- Limit: payment processing
- A Trustpilot reviewer reported waiting 72 hours for a purchase payment to process, although support responded and later offered compensation.Read 15 Oct 2026 · trustpilot.com
- Loudness metering
- It provides EBU R128/LUFS and unweighted K-system metering.Read 15 Oct 2026 · voxengo.com
- Maker and history
- Voxengo says it is privately owned by Aleksey Vaneev and began as a full-time commercial endeavor in December 2002; the page does not state a headquarters location.Read 3 Oct 2026 · voxengo.com
- Maker location
- Aleksey Vaneev's public developer profile lists Syktyvkar, Komi, and links Voxengo as his main occupation.Read 15 Oct 2026 · github.com
- Maker ownership
- Voxengo is a registered trademark privately owned by Aleksey Vaneev.Read 15 Oct 2026 · voxengo.com
- Metering
- It includes EBU R128 and K-system metering, RMS and true-peak level measurement, clipping detection, and a stereo correlation meter.Read 3 Oct 2026 · voxengo.com
- Multi-channel features
- SPAN supports multi-channel analysis and can display spectra from two channels or channel groups at the same time.Read 3 Oct 2026 · voxengo.com
- Notable news
- Voxengo announced suspension of international software sales in October 2024, attributing the change to its payment company's contract cancellation and sanctions-related concerns.Read 15 Oct 2026 · voxengo.com
- Open-source status
- SPAN is presented as freeware, while Voxengo separately identifies other projects as open source; SPAN source code is not offered on its product or download pages.Read 15 Oct 2026 · voxengo.com
- Peak and clipping tools
- Output statistics include RMS, true-peak, headroom, and clipping detection.Read 15 Oct 2026 · voxengo.com
- Plugin formats
- The maker lists VST, VST3, AudioUnit, and AAX compatibility.Read 3 Oct 2026 · voxengo.com
- Praise: Bonedo testing
- Bonedo found the interface generally understandable, the frequency-solo function useful, and multi-channel analysis effective, with no crashes during testing.Read 15 Oct 2026 · bonedo.de
- Praise: KVR reviewers
- KVR users repeatedly praise SPAN's extensive settings, mid-side and channel views, stability, precise measurements, and zero purchase cost.Read 15 Oct 2026 · kvraudio.com
- Praise: mastering utility
- MusicRadar described SPAN Free as useful for detecting clipping, managing peaks, and examining stereo, mid-side, and surround material.Read 15 Oct 2026 · musicradar.com
- Praise: MusicRadar
- MusicRadar highlighted SPAN's mono, stereo, mid-side, surround, K-metering, correlation, and configurable FFT features and said the free version is sufficient for most users.Read 15 Oct 2026 · musicradar.com
- Privacy and security
- Voxengo's site privacy policy says it anonymizes IP addresses before storing them in its long-term database and uses security technologies and procedures to help protect personal information.Read 3 Oct 2026 · voxengo.com
- Processing
- SPAN uses 64-bit floating-point processing and supports all sample rates.Read 15 Oct 2026 · voxengo.com
- Rating on Bonedo
- 5 out of 5 from 1 test review.Read 15 Oct 2026 · bonedo.de
- Rating on KVR Audio
- 4.89 out of 5 from 9 reviews.Read 15 Oct 2026 · kvraudio.com
- Rating on Trustpilot
- 3.8 out of 5 from 2 reviews.Read 15 Oct 2026 · trustpilot.com
- Routing
- Internal channel routing and channel grouping allow simultaneous analysis of different channels or groups.Read 15 Oct 2026 · voxengo.com
- Security and privacy
- Voxengo's privacy policy says the site may collect contact details, browser and operating-system information, IP address, access times, and referring-site data.Read 15 Oct 2026 · voxengo.com
- Spectrum controls
- Users can set FFT block size, window overlap, visual slope, secondary spectrum display, and visual smoothing.Read 3 Oct 2026 · voxengo.com
- Spectrum views
- The plugin analyzes stereo, mono, mid-side, 5.1, and 7.1 signals.Read 15 Oct 2026 · voxengo.com
- System requirements
- The stated minimum is a 2.5 GHz dual-core processor and 4 GB RAM; Windows XP/Vista/7/8/10 and later plus macOS 10.12 and later are listed, with Apple Silicon and current macOS versions supported.Read 15 Oct 2026 · voxengo.com
- Workflow controls
- The feature list includes presets, undo/redo history, A/B comparisons, contextual hints, and resizable windows.Read 15 Oct 2026 · voxengo.com
Plans and prices
Voxengo SPAN Free Free real-time FFT spectrum analyzer plugin Read 3 Oct 2026 · voxengo.com
Voxengo SPAN free Free Freeware FFT analyzer · requires compatible audio host · Windows/macOS plugin formats Read 15 Oct 2026 · voxengo.com
Strong points and limits
Strong points
- Free real-time FFT spectrum analysis
- Includes EBU R128 and K-system metering
- Analyzes stereo, mid-side, and surround signals
- Offers VST, VST3, AAX, and Mac AudioUnit formats
Limits
- Requires at least 4 GB of RAM
- Spectrum import and export is a SPAN Plus feature
- Free-plugin comparison workaround works only in some hosts
Who it suits
SPAN suits audio and music production users who want real-time spectrum analysis and level metering inside a compatible plugin host. Its channel and surround views may be useful for multichannel work.
Verdict
SPAN combines spectrum controls with a broad set of metering and multichannel analysis features. Track-to-track spectrum import and export is not part of the free plugin.
Where Specifiction places it
- Audio Analysis Software#21 of 437.9
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